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12/05/2019 YamEen Uncategorized

7 Human Population and Environment part 1

7 Human Population and Environment

Introduction
Human society is governed by interaction and cooperation with other human beings.
Latest trends in technology and medical knowledge are available to control human population
growth and to improve the health. Still population continues to increase and poverty become
greater than ever before. Humans are social animals who have freedom of choice. They
largely take decision by heart rather than mind. It is evident from historical records, social
situations, ethical and religious considerations and personal desires. Today the greatest
hindrance to controlling human population is no more biological but falls into the province
of philosophers, theologians, politicians, sociologists, and others. The cause of the population
problem is to be understood if we are to deal successfully with the population problem.
Carrying Capacity
The carrying capacity of an area is the number of individuals of a species that can
survive in that area over time. In most populations, four broad categories of factors determine
the carrying capacity for a population. These factors are: (1) the availability of raw materials,
(2) the availability of energy, (3) the accumulation of waste products and their means of
disposal and (4) interactions among organisms. The total of all of these forces acting together
to limit populations size is known as environmental resistance, and certain limiting factors
have a primary role in limiting the size of a population. In some cases, these limiting factors
are easy to identify and may involve lack of food, lack of oxygen, competition with other
species, or disease.
Population Characteristics
A population can be defined as a group of individuals of the same species inhabiting
an area. Some of the characteristics or a population are nasality (birth rate), mortality
(death rate), sex ratio, age distribution, growth rates, and special distribution.
Natality refers to the number of individuals added to the population through
reproduction. In human populations, natality is usually described in terms of the birth
rate, the number of individuals born per one thousand individuals in the population per
year. It is important to recognize that the growth of a population is not determined by the
birth rate (natality) alone.
This is expressed as
B (Natality rate) = Nn/t which means = No. of new individuals added to population time.
Mortality is the number of deaths per year. In human population studies, mortality is
usually discussed in terms of the death rate, the number of individuals who die per one
thousand individuals in the population per year.
Population Density is population size in relation to some unit of space and time. It
varies with food availability and climatic conditions. It can be measured as:
D = N/a
t
where D is population density, n = number of individuals, a = area and t = time.
Population Age Distribution refers to the individuals of different age groups in a
population. The natality and mortality is also different for respective ages. Bodenhelmer
(1938) recognized three ecological ages as: (i) Pre reproductive, (ii) Reproductive and
(iii) Post reproductive Fig. 1. Duration of these ages varies in different organisms e.g.
Insects have a very long pre-reproductive period, a very short reproductive period but no
post reproductive period at all. In man all the three stages are equal in length.
Post reproductive
Reproductive
Pre reproductive
Age structure
Expanding
Population
(A)
(B) Stable (C)
Population
Dim inishing
Population
Type of Population
Figure 7.1. Age structure in different types of populations
Biotic Potential is the maximum reproductive power. The constant percent growth
rate of a population under optimum environmental conditions thus represents its biotic
potential or reproductive potential. Letter designates it g.
g
AN AT
N
=
∆ /
where, N = number, t = time, D = constant.
The sex ratio refers to the number of males relative to the
Number of females in the population.
The Human Population Issue
Current population growth has led to famine in areas where food production cannot keep
pace with population growth; political unrest areas with great disparities in availability of
resources (jobs: goods, food); environmental degradation by poor agricultural practices (erosion,
desertification); water pollution by human and industrial waste; air pollution caused by the
human need to use energy for personal use and for industrial applications; extinctions caused
by people converting natural ecosystems to managed agricultural ecosystems; and. destructive
effects of exploitation of natural resources (strip, mining, oil spills, groundwater mining). In
addition to population size, the kind of demands a population places on its resources is also
important. Highly industrialized populations require much more energy and material resources
to sustain their way of life than do the populations of the less-developed world.
A Population Growth Curve
Sex ratios and age distributions within a population directly influence the rate of
reproduction within a population. Each species has an inherent reproductive capacity, or
biotic potential, which is its ability to produce offspring. However, this high reproductive
potential results in a natural tendency for populations to increase. For example, two mice
produce four offspring, which, if they live, will also produce offspring while their parent’s
are also reproducing. Therefore, the population will tend to grow in an exponential fashion.
Population growth tends to follow a particular pattern, consisting of a lag phase, an
exponential growth phase, and a stable equilibrium phase. Fig. 15 shows a typical population
growth curve. During the first portion of curve, known as the lag phase, the population
grows very slowly because the process of reproduction and growth of offspring takes time.
Most organisms do not reproduce instantaneously but must first mature into adults. Mating
and the development of the young ones into independent organisms follow this period. By
the time the first batch of young has reached sexual maturity, the parents may be in the
process of producing a second set of offspring. Since more total organisms now are reproducing,
the population begins to increase at an exponential rate. This stage in the population growth
curve is known as the exponential growth phase. This growth will continue for as long as
the, birth rate exceeds the death rate. Eventually, however, the death rate and the birth
rate will come to equal one another, and the population will stop growing and reach a
relatively stable population. size and is said to be the stable equilibrium phase. Hence,
populations cannot grow continuously because of the concept of carrying capacity.
(a) S-Shaped growth curve
When a species is introduced into a new habitat, the population grows exponentially until
the individuals become numerous. The further increase in their number is checked by the
environmental resistance factors that the population growth declines until zero population
growth is reached. (i.e. constant) and it becomes stable (K). Such curves are called sigmoid
curves.
The study of growth curves in S-shaped growth pattern is a self-limiting one where the
rate of growth is more and more as density increases. If the limitation is linearly proportional
to density we get a symmetrical S-curve so as to approach upper level or limit-K, the
carrying capacity. This pattern enhances stability as population regulates itself. Actually
the density often overshoots or is more than K and because of time lags in feedback control
resulting in oscillations as shown in graphs.

K (Carrying Capacity)
Steady State
Exponential Growth
(Log Phase) M ax. G rowth
Log Phase
Slow Growth
Figure 7.2. S-shaped growth curve.
(b) J-Shaped growth curve
The population increases whenever there is an increase in birth rate over death rate.
The factors of environmental resistance do not check population growth or stabilize the
growth (zero growth not established) then a J-shaped curve is obtained Fig. 3. It is hard to
speculate in the future of human population growth curve whether it will be S-shaped or
J-shaped. Growth curve are thus the graphical representation of a population in given time
period. It may be of S-shaped or J-shaped as mentioned.
Time
Populatio n Growth
Lim it
Figure 7.3. J-shaped growth curve.
When population increase in exponential (E) or geometric fashion (e.g. 2, 4, 8, 16, 32
………) until the population runs out of some resources or encounters, some other limitation
(N). Growth then comes to a more or less abrupt halt in such cases and density usually
declines rapidly until conditions for another rapid growth is restored. Population with this
kind of growth form instability unless regulated by factors outside the population.
(i) Growth rate decreases as density increases. (Self-limiting or inverse density dependent type.)
(ii) Growth rate is high until density become high and factors from outside of the
population become limiting. (Density independent type.)
(iii) Growth rate is highest at intermediate density.
Causes of Population Growth
There is an ultimate carrying capacity for the human population and limiting factors
will come into play to cause populations to stabilize. However, unlike populations of other
kinds of organisms, human populations are also influenced by a variety of social, political,
economic, and ethical factors. Humans have accumulated knowledge that allows for predictions
about the future and can make conscious decisions based on the likely course of events and
adjust their lives accordingly. Part of that knowledge is the certainty that as populations
continue to increase, death rates and birth rates will become equal. This can be accomplished
by allowing the death rate to rise or by choosing to limit the birth rate. It would seem that
controlling human population should be a simple process. Once everyone understands that
lowering the birth rate is more human than allowing the death rate to rise, most people
should make the “correct” decision; however, it is not quite that simple.
Biological Reasons for Population Growth
The study of human populations, their characteristics, and what happens to them is
known as demography. Demographers can predict the future growth of a population by
looking at several different biological indicators. When we look at birth rates and death
rates in various countries of the world, in almost all cases the birth rate exceeds the death
rate. Therefore, the size of the population must increase. Some countries that have high
birth rates and high death rates, with birth rates greatly exceeding the death rates, will
grow rapidly (Afghanistan and Ethiopia). Such countries Usually have an extremely high
mortality rate among children because of disease and malnutrition. Some countries have
high birth rates and low death rates and will grow extremely rapidly ~Guatemala and
Syria). Infant mortality rates are moderately high in these countries. Other countries have
low birth rates and death rates that closely match the birth rates and will grow slowly
(Sweden and the United Kingdom). These and other more, developed countries typically
have very low infant mortality rates.
Obviously, the most important determinant of the rate at which human populations
grow is related to the number of women in the population who are having children and the
number each will have. The total fertility rate of a population is the number of children
born per woman per lifetime. A total fertility rate of 2.1 is known as replacement fertility,
since in the long run, if the total fertility rate is 2.1, population growth will stabilize. When
population is not growing and the number of births equals the number of deaths, it is said
to exhibit zero population growth. The age structure of a population also has a great deal
to do with the rate of population growth. If a population has a large number of young people
who are in the process of raising families or who will be raising families in the near future,
the population will continue to increase even if the families limit themselves to two children.
Factors Controlling Population Growth
Man is the only one who has regulated his population by developing new astonishing
technologies for better and secured future on one hand. And on other hand, created a
problem of population explosion. Some factors are:
(i) Famines in a country or state lead to destruction.
(ii) Natural calamities like floods, droughts, earthquakes and volcanic eruptions,
hurricanes etc. lead to death of thousands of people.
(iii) Epidemic diseases, endemic diseases wipe a big number of populations.
(iv) Wars cause heavy casualties.
(v) Unnatural accidents caused during transportation, fires etc. Some factors that have
helped the population growth are:
(a) High production of food and better technologies for storage, processing and
distribution.
(b) Better medical facilities provided during childbirth and under five years age
by immunization.
The factors are many but they can be grouped into three as:
(i) Geographic factor: Like climate, soil, water, mineral resources, transportation
etc.
(ii) Demographic factor: Like birth rates (natality), death rates (mortality), sex ratio
etc.
(iii) Socio-economic factors: Like marriages, job availability, resources etc.
In the developed countries, population has started declining because of-
(i) Better medical and family planning facilities.
(ii) The low death and high birth rates. .
(iii) The educated people who know about ‘the abuses of over population have
small family.
Population and Standard of Living
Standard of living is a difficult concept to quantify since different cultures have different
attitudes and feelings about what is good and desirable. Here, we compare averages of
several aspects of the cultures in three countries: (1) the United States, which is an example
of a highly developed if industrialized country; (2) Argentina, which is a moderately developed
country; and (3) Zimbabwe, which is less developed. Obviously, tremendous differences exist
in the standard of living among these three countries. What the average U.S. citizen would
consider a poverty level of existence would be considered a luxurious life for the average
person in a poorly developed country. Standard of living seems to be closely tied to energy
consumption.
Population Explosion-Family Welfare Programme
Growth of Human Population
Emigration: The number of individuals going out from a population to join another
population in a new locality resulting in decrease of the original population.
Immigration: It is the addition of new individuals to the population from other
localities.
Density dependent factors: An increase in population leads to competition, since
all its individuals have identical requirements for food and space. Population increase
causes scarcity of food, consequently leading to death due to starvation.
Density independent factors: Interaction between populations in a given area
can lead to mutual benefits, to competition for resources or dependence of one on
the other.

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12/05/2019 YamEen Uncategorized

6 Environmental science Social Issues part 4

Indian scenario
Laws need to be strengthened and implemented properly to protect the environment.
Although India has a number of rules and regulations to protect the environment they have
still not reached the stage of full compliance. The growth of environmental laws is a reflection
of the speed with which environmentalism has established itself as a potent political force.
But many of the laws are either trivial or short-lived and vulnerable to political pressure.
Politicians do not violate laws, but the laws are so modified to suit their vested interests.
Environment regulations may thus be modified to tap the tourist potential of an area or to
set up some other industry. There have been many instances where laws have been changed
to accommodate commercialization in hill areas.
The Wildlife (Protection) Act, 1972, gives wildlife wardens the power to protect animals
in wildlife parks and sanctuaries. But we also find that these wardens exercise their power
on traditional entertainers. Monkey, bear and snakes shows on streets are a common scene.
The state earns money by putting wild animals on exhibition in zoological parks and permits
circus companies to train animals for entertainment to earn profit. Environmental values
are difficult to integrate into Indian law. Though regulatory controls have become stricter,
the state of the environment has not improved because of the financial crunch, absence of
basic infrastructure, reliance on litigation, absence of comprehensive industrial location
policy and absence of relevant technology.
In India, several legislations have been passed to check pollution, such as the Air
(Prevention of Pollution) Act, Water (Prevention and Control of Pollution) Act, Environment
(Protection) Act. The legislation on air has some loopholes since it does not provide for the
prevention of interstate air pollution. It deals with the control of noxious emissions from
specified industrial processes, automobiles and noise pollution. Smoke and other non-noxious
emissions are not covered under this Act. There has to be transparency in the judicial
system. The public has the right to know what is going on. The judiciary has to think before
passing judgments. Without thinking of alternatives’ such as rehabilitation, these verdicts
will just continue to push up the cost of illegal management.
Public Awareness
Environmental Science aims at creating understanding among masses of the delicate
balance, which exists, between natural environment and its dependents (humans) to optimize
the exploitation of resources on economic basis, which would lead to sustainable development.
Secondly, it encourages students and researchers to make careers in the field of environment
knowledge of the basic principles of ecology and environmental science would inbuilt a sense
of duty in the citizens to care and. manage the natural resources on an optimal basis. Such
awareness is essential because the causes and solutions to environmental problems are
often linked.
Public awareness addresses issues by which a common man becomes aware of activities,
which would result in improvement of the overall environment When public awareness rises
to a level where masses come to know the do’s and don’ts of the environment, the rules and
regulation have little role to play. People should understand that how they should. react to
pollution’ problems, natural hazards, anthropogenic hazards, waste-disposal problem, hunting,
deforestation and ecosystem problems (bio-magnification, food chain and food web concept).
Public awareness increase upon making the people understand how malpractices affect
environmental systems and in turn how environmental systems affect whom. But one
important question arises here. Who would inform whom and when? Public participation in
environmental decision-making can help to a great extent. Their participation has both
moral and practical implications.
Environmental awareness increases easily in financially stable and better-educated
people through book reading, films, newspaper, magazines and other electronic media.
Nongovernmental organizations (NGOs) can play a better role in spread of information ‘up
to village levels. Addressing issues of environmental significance to private voluntary
organizations, NGOs, farmers, organizations, cooperatives, schools, universities – and private
entrepreneurs, can increase public awareness. Thiswould bring more information to bear
on the planning process. Among the various sources, which can increase the public awareness
the role of mass media, is vibrant. It is so because people love to watch T.V., listen radio,
read newspaper and magazines.
Suggestions
• It is an effective tool for the spread of Environmental Science.
• Media people should be trained in addressing environmental issues to the public.
• Special employees should be deputed in press, radio and T.V. media.
• Environmental folk plays, puppet shows etc. should be organized to make the
ignorant and simple people aware of the present day problems.
• Drawing, craft and essay writing contests can be used as an effective tool at school
level.
• Visual, and calligraphic displays should be mounted in trains and buses as these
are used by common masses.
• Storybooks and cartoon network can help the future generation to mould itself
according to environmental needs.
QUESTIONS
1. What do you understand by the word sustainable development? Explain.
2. What are urban problems? How we can solve the problem related to water conservation?
3. What are the ways to resettlement and Rehabilitation of people affected by the pollutions?
4. What are the environmental ethics? Write in 200 words.
5. Explain the Environment Protection Act in your own words.
6. What are the issues involved in enforcement of environment legislation?

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12/05/2019 YamEen Uncategorized

6 Environmental science Social Issues part 2

Rehabilitation should be collective
In the villages, almost each’ family depends on the other. The social and moral obligations
towards each other bind them into one cohesive whole. The authorities are rehabilitating
individual families and not the village as a whole.
Monetary Compensation
Mere payment of cash is not rehabilitation. Moreover, the amount of cash paid as
compensation is insufficient to buy land in other places because of the high rates. The
oustees being basically farmers lack the business acumen needed to set up a viable commercial
alternative. Since they are not accustomed to having such large sums (relative to their
usually small incomes) in a lump sum, they are ignorant as to how they should spend it.
Mismanagement
The project authorities estimated the total affected population in 1981 as 46,000. Using
the Census Office figures, the total number affected for 1981 is act 70,000.
Lack of Public Relations
The majority of populace to be displaced consists of advises, tribal, scheduled castes
that have a unique lifestyle. The traumatic experience of shifting to new areas and new
occupations involving drastic changes in their lifestyle weighs heavily on these people. The
absence of any public relation efforts has further aggravated the situation.
Housing compensation: It is necessary to highlight a major flaw in the procedure for
fixed immovable property like houses, well, barns fence, cattle-stalls, etc. The present
procedure evaluates the “current worth” or “value after depreciation” for determining the
amount of compensation. This concept is faulty. He should be paid an amount for his house
etc., equivalent to the cost of reconstructing a dwelling place equal to the plinth area lost
under submergence. This amount (i.e., replacement cost) will obviously be more than the
“current worth” of his old dwelling.
Environmental Ethics
The Earth is unique among all the planets in our solar system. It is endowed with
plentiful resources. Man’s greed to raise his standard of living compels him control and tap
natural resources. Many. rivers throughout the world have been “controlled” to provide
power, irrigation, and navigation for the people at the expense of the natural world. If such
gifts of nature are not tapped for resource generation, many people think it to be wastage
of resources. The capitalists want to use the forests for timber production and not doing so
is closely linked to economical hardships. Removing the trees would destroy something that
took hundreds of years to develop and may never be replaced. Efforts to manage the
interactions between people and their environment are an age-old practice. At one time,
pollution was a local, temporary event, but today, pollution problems have crossed
international borders and have become global. The seminars over chemical and radioactive
waste disposal witness the increasingly international nature of pollution.
Ethical issues dealing with the environment are no different from other kinds of problems.
The concept of an environmental ethics could encompass differing principles and beliefs.
Ethics is one branch of philosophy, which fundamentally attempts to define what is right,
and what is wrong, regardless of cultural differences. Environmental ethics are formulated
on the basis that human beings are also a part of nature and nature has many interdependent
components. In any natural ecosystem, the well being of the individual and of each species
is linked to the well being of the entire community. In a world increasingly without
environmental borders, nations, like individuals, should have a fundamental ethical
responsibility to respect nature and to care for the Earth, protecting its life-support systems,
biodiversity, and beauty, caring for the needs of other countries and future generations.
Environmental ethicists argue that to consider environmental protection as a “right” of the
planet is a natural extension of concepts of human rights.
Although there are many different attitudes about the environment. Three types of the
ethics are identified as (a) the development ethic, (b) the preservation ethic, and (c) the
conservation ethic. Each of these ethical positions has its own appropriate code of conduct
against which ecological mortality may be measured.
The development ethic is based 011 actions. Development in any sector is inevitable.
. But the development should not crop up at the cost of environmental failure. This philosophy
is strengthened by the idea that, “if it can be done, it should be done.”
The preservation ethic considers nature special in itself. Some preservationists have
an almost religious outlook regarding nature. They believe that nature is beautiful place to
live in and it should be maintained for feeding, breeding, enjoyment and peace. On the other
hand scientific outlook argue that the human species depends on and has much to learn
from nature. Rare and endangered species and ecosystems, as well as the more common
ones, must be preserved because of their known or assumed long-range, practical utility.
The third environmental ethic is referred to as the conservation ethic, It recognizes
the desirability of decent living standards, but it works towards a balance of resource use
and resource availability.
Economic growth and resource exploitation are attitudes shared by developing
societies. As a society, we continue to consume natural resources as if the supplies were
never ending. All of this is reflected in our increasingly unstable relationship with the
environment, which grows out of our tendency to take from the “common good” without
regard for the future.
Global Environmental Ethics
This new sense of urgency and common cause about the environment is leading to
unprecedented cooperation in some areas. Ecological degradation in any nation almost
inevitably impinges on the quality of life in others. For years, acid rain has been a major
irritant in relations between the United States and Canada.
Conclusion
Will the nations of the world be able to put aside their political differences to work
towards a global environmental course of action? Out of that international conference was
born the U.N. Environment Programme a separate department of the United Nations that
deals with environmental issues. Through organizations such as this nations can work
together to solve common environmental problems. Deep ecologists, on the other hand, see
humankind itself as the main problem. They believe that the earth is a complex organism
with its own needs, metabolism; and immune system and that humankind’s relationship
with the earth is increasingly parasitic. In the book Deep Ecology: Living Nature. As If
Nature Mattered, proponents Bill Devall and George Sessions, clearly state their principles:
(1) Humans have no right to reduce the richness and diversity of life except to satisfy vital
needs: (2) the quality of human life and culture is compatible with a substantial decrease
in the human population; and (3) the flourishing of non-human life requires such a decrease.
To secure for current and future generations a safe and healthy environment, a sound
and prosperous economy should aim at:
1. Ensure that citizens today and tomorrow have the clean air water, and land essential
to sustaining human health and the environment.
2. Protect and enhance, the quality of water resources and promote the wise and
efficient use of water.
3. Maintain and enhance the health and diversity of the wildlife and planets.
4. Develop an environmentally literate society.
Climate Change
Introduction
The recent interest in global warming and sustainable development has become a
global talk. The most important global environmental topics as chosen by a panel of about
12 world experts were as follows: human population growth, bio-diversity and conservation,
climate change, forest decline, hazardous wastes, land degradation, human pathogens, urban
environment, work environment and resource depletion. Man is as closely related to nature
as he is to himself, because he is a part of it. An outright dependence on nature has been
a striking feature of man’s progress through the centuries of his struggle.
Climate has from the very beginning regulated man in practically every aspect of life
and has played a very important role in the development of civilizations all around the
world. Man’s impact on climate began 5000 to 9000 years ago, as he was able to alter the
environment by burning and felling forest and tilling the earth. The most extensive change
wrought by man prior to our own times was the gradual conversion of most of the temperate
forest zone to crops that is an artificial steppe or savanna. Thus until the industrial revolution
and probably until the present century, man had little effect on the climate except on a very
local scale.
Presently global warming has emerged as one of the most important environmental
issues ever to confront humanity. This concern arises from the fact that our everyday
activities may be leading to changes in the earth’s atmosphere that have the potential: to
significantly alter the planet’s heat and radiation balance, and thereby lead to a warmer
climate in the next century and thereafter. International efforts to address this problem
have been on for the last decade, with the Earth Summit at Rio in 1992 as an important
launching point and the Conference of Parties in Buenos Aires. In 1998 as the most recent
step. Although India as a developing country does not have any commitments or
responsibilities at present for reducing the emissions of greenhouse gases such as carbon
dioxide (CO2) that lead to global warming, pressure is increasing on India and other large,
rapidly developing countries such as China and Brazil to adopt a more pro-active role.
What is Climate Change?
Climate change is a newcomer to the international political and environmental agenda,
having emerged as a major policy issue only in the late 1980s and thereafter. It has emerged
since the 19th century that CO2 in the atmosphere is a ‘greenhouse gas’, that is, its presence
in the atmosphere helps to retain the incoming heat energy from the sun, thereby increasing
the earth’s surface temperature. Of course, CO2 is only one of several such greenhouse gases
in the atmosphere. Others include methane, nitrous oxide and water vapour. However, CO2
is the most important greenhouse gas that is being affected by human activities. CO2 is
generated by a multitude of processes. Since the Industrial Revolution, when our usage of
fossil fuels increased dramatically, the contribution of CO2 from human activities has grown
large enough to constitute a significant perturbation of the natural carbon cycle.
The concentration of CO
2 in the Earth’s atmosphere was about 280 parts per million by
volume (ppmv) in 1750, before the Industrial Revolution began. By 1994 it was 358 ppmv
and rising by about 1.5 ppnw per year. If emissions continue at the 1994 rate, the
concentration will be around 500 ppmv, nearly double the pre-industrial level, by the end
of the 21st century.
Rising Concentrations
The effect is that the atmosphere retains more of the Sun’s heat, warming the Earth’s
surface. While the pattern of future warming is very much open to debate, it is indisputable
that the surface of the Earth has warmed, on average, 0.3 to 0.6 °C since the late 19th
century when reliable temperature measurements began. Under the existing scenarios of
economic growth and development leading to greenhouse gas emissions, on a worldwide
average, temperatures would rise by 1 to 3.5 °C by the year 2100, and global mean sea level
by about 15 to 95 cm. It is likely that changes of this magnitude and rapidity could pose
severe problems for many natural and managed ecosystems. Indeed, for many low-lying and
deltaic areas and small islands, a sea level rise of one meter could threaten complete Joss
of land and extinction of habitation.
Extreme Weather Events
In addition, most of the ill effects of climate change are linked to extreme weather
events, such as hot or cold spells of temperature, or wet or dry spells of rainfall, or cyclones
and floods. Predictions of the nature and distributions of such events in a changed climate
are even more uncertain- to the extent that virtually no authoritative predictions exist at
all. While there are costs as well as benefits associated with climate change, the scientific
consensus is clearly that the overall effects are likely to pose a significant burden on the
global community. Unlike many other environmental issues, such as local air or water
pollution, or even stratospheric ozone depletion caused by chlorofluorocarbons (CFCs), global
warming poses special challenges due to the spatial and temporal extent of the problem
covering the globe and with decades to centuries time scales.
Analysis and assessment of just what steps needed to be taken to limit greenhouse gas
emissions. This process resulted in the negotiation’ of a protocol, the final details of which
were completed at the third meeting of the Conference of the Parties to the Framework
Convention held December 1-12, 1997, in Kyoto, Japan. The Kyoto Protocol to the United
Nations Framework Convention on Climate Change commits industrialized nations to specific,
legally binding emission reduction targets for six greenhouse gases: carbon dioxide, methane,
nitrous oxide, hydro fluorocarbons, per-fluorinated compounds and sulphur hex fluoride.
First, although India does not currently have any obligations under the Convention to
reduce its greenhouse gas emissions. It is important for us to develop a clear understanding
of our emission inventory. We also need to document and analyze our efforts in areas such
as renewable energy, wasteland development and a forestation – all of which contribute
towards either reducing CO2 emissions or increasing CO2 removal from the atmosphere.
Considering that these efforts may often be undertaken for a variety of reasons not directly
related to global warming, but yet has benefits as far as climate change is concerned, we
may be able to leverage such efforts in the international context. The Research community
could contribute substantially in this regard. We need to significantly improve our ability
to plan and adapt to extreme events such as floods, droughts, cyclones and other meteorological
hazards. Any robustness that we build into the system in this regard will always stand us
in good stead no matter what climate change actually transpires.

Global Warming and the Greenhouse Effect

In the late 1900’s researchers realized that the world may be getting warmer. The last
two decades of the 1900’s witnessed some warm and cool years. However, not enough
evidences were available to support the theory of global warming. But this a well-known fact
that accumulation of several green house gases can lead to a rise in temperature (global
warming). If a global warming phenomenon sets in this would result in major changes in
world’s climate. The increase in temperature might lead melting of snow on poles, which
would terrifically add, to ocean waters. Hence the level of seas, and oceans would rise, this
would largely affect the coastal areas. These would submerge under coastal Waters due to
expansion of seas and oceans. Besides the Temperate climate pattern would shift northward
and present temperate regions would become hot & dry.
The Greenhouse Effect is a natural phenomenon that plays a central role, in determining
the earth’s climate. The hot surface of the sun radiates heat and light energy. Several gases
in the atmosphere are transparent to light but absorb infrared radiation. These allow sunlight
to pass through the atmosphere and be absorbed by the earth’s surface. This energy ,is
again radiated as heat energy, which is absorbed by the gases. As the effect is similar in
nature to what happens in a’ botanical greenhouse (the glass panes allows the light energy
to enter inside but diminishes the loss of heat), these gases are called greenhouse gases and
the resultant warming from their increase is called the greenhouse effect. Anthropogenic
activities add to the phenomenon accelerating greenhouse gas building process. Global increase
of greenhouse gases in the atmosphere viz., carbon dioxide, nitrous oxide, methane and
chlorofluorocarbons are now well documented. In addition to all these changes, troposphere
and stratospheric chemistry are being modified due to the addition of these gases as well
as emission of carbon monoxide, nitrogen oxides and other compound. The United State
Environmental Protection Agency, Office of Policy, Planning and Evaluation in 1989 have
documented the increase of the different green house gases.
Table 6.1: Major Green House Gases Contributing to Global Warming
Sl.No. Gas Contribution to global
warming
1. Carbon dioxide 57
2. Chlorofluorocarbons 25
3. Methane 12
4. Nitrous oxide 6
The concentration of carbon dioxide into the atmosphere has increased by 25% since the
industrial revolution. Carbon dioxide is increasing at a rate of about 0.4% per year and is
responsible for about half of the current increases in the greenhouse effect. The concentration
of methane has more than doubled during the last three centuries. Agricultural sources
particularly rice cultivation and animal husbandry has probably been the most significant
contributors to historical increase in concentrations. But there is the potential for rapid
growth in emissions from landfills, coal seems, permafrost, natural gas explorations and
pipeline leakage, and biomass burning associated with forest clearings in the future.
The concentrations of nitrous oxide have increased by 5-10% since pre-industrial times.
The cause of this increase is highly uncertain, but it has been understood that the use of
nitrogenous fertilizer, land clearing biomass burning and fossil fuel combustion have all
contributed. Nitrous oxide is currently increasing at a rate of about 0.25% per year, which
represents and imbalance between sources and sinks of about 30%. CFC’s were introduced
into the atmosphere for the first time during the century; the most common species are
CFC-12 and CFC-II. Of major concern because of their potential to deplete stratospheric
ozone, the CFCs also represent about 15% of the current increases in the greenhouse effect.
The chemistry of the atmosphere is changing due to emission of carbon monoxide,
nitrogen oxides, and volatile organic compounds, among other species, in addition to the
changes in the greenhouse gases already described. This alters the amount and distribution
of ozone and the oxidizing power of the atmosphere. which changes the lifetimes of methane
and other greenhouse gases. Changes in global ozone are quite uncertain, and may have
contributed to an increase or decrease in the warming commitment during the last decade.
Acid Rain
Although the phenomenon of “acid rain” (more correctly acid deposition) was identified
in Manchester, England, as long ago as 1852, and described more thoroughly in 1872,
modern scientific research has been going on only since the mid-1950s. Public concern about
the problem began in the late 1960s. Acid rain is an environmental hazard that is transponder
in nature. Northeastern America, North Western Europe and India are facing an acute
problem of acid rain. Acid rain has affected certain rivers, lakes, streams and forests in
United Kingdom (UK), United States of America (USA), Germany and many other countries.
Acid rain literally means ‘the presence of excessive acids in rain waters’. Acid precipitation
is a mixture of strong mineral acids sulphuric acid (H2SO4), nitric acid (HNO3) and in some
locations, hydrochloric acid (HCl). It usually has a ph of less than 5.6, the value of distilled
water in equilibrium with atmospheric carbon dioxide.
Acid in the Rain Water’s
Acid rain problem is a result of anthropogenic activities. Most acids come from cars,
homes, industries and power stations but some share is contributed by natural sources such
as volcanoes, swamps and planktons. The acid problem is basically associated with the
transport and subsequent deposition of oxides of sulphur, nitrogen and their oxidative
products. These are produced by combustion of fossil fuels, power plants, automobile exhausts
and domestic fires etc.
Formation of Acid Rain
Acid rain is one of the form of acid deposition which can either be wet or dry, acid rain,
snow, dew, fog, frost and mist are the wet form of deposition, while dust particles containing
sulphate and nitrates which settle on ground is called dry deposition.
Wet Acid Rain
Coal, fuel wood or petroleum products have sulphur and nitrogen. These elements,
when burnt in atmospheric oxygen,’ are converted into their respective oxides (SO2 and
NO
3), which are highly soluble in water. By anthropogenic and by natural sources, oxides
of sulphur and nitrogen enter the atmosphere.
Reactions
Reaction with Sulphur
S + O
2 = SO2
2SO
2 + O2 = 2SO3
Reaction with Nitrogen
NO + O
3 = NO2 + O2
NO
3 + NO2 = N2O5
When air is saturated with water droplets (humid conditions), N2O5 invariably reacts
with water vapors to form droplets of HNO3.

N2O5 + H2O = 2HNO3Besides some HNO2 is also formedN2O3 + H2O = 2HNO2SO3 in humid conditions forms droplets of H2SO4.SO2 + 1/202O2 + H2O = H2

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12/05/2019 YamEen Uncategorized

6 Environmental science Social Issues part 3

Scientific Programmes an Other Activities of International Organizations
The UNEP (United Nations Environment Programme), UNDP (United Nations
Development Programme) are some of the environment programmes, which are making
active efforts and are doing research in this field. Apart from them, Economic Commission
for Europe (ECE), the European Economic Community (EEC), the European Science
Foundation (ESF), The Food and Agricultural Organization (FAO), International Social
Science Council (lSSC), World Meteorological Organization (WMO), The Inter-governmental
Oceanographic Commission (IOC) – this a part of UNESCO, the Scientific Committee on
Ocean Research (SCOR) and many other such organizations. Apart from them there are
other scientific activities underway which are funded by different organizations such as the
World’ Weather Watch (WWW), World Climate Research Programme (WCRP), World Climate
Programme (WCP), World Climate Impact Studies Programme (WCIP), Past Global Change
(PAGES), Integrated Global Ocean Station System (IGOSS), (Human Dimension of Global
Change (HDGC), Global Environment Monitoring System (GEMS), Global’ Change and
Terrestrial Eco-System (GCTE).
The Earth’s atmosphere is being changed at an unprecedented rate by pollutants resulting
from human activities, inefficient and wasteful fossil fuel use and the effects of rapid
population growth in many regions. Global climate is changing because of the build up in
the atmosphere of carbon dioxide methane, nitrous oxide, the CFC’s (powerful greenhouse
gases as well as destroyers of stratospheric ozone), and other greenhouse gases produced by
fossil fuel burning, by deforestation and by producing food for the rapidly increasing population
at a global level.
Wasteland Reclamation
What is land degradation? Land degradation refers to the physical or chemical processes,
which make land, unfit for a variety of purposes like agriculture, commercial, residential
etc. Why land becomes degraded? Geological processes and anthropogenic activities are
chiefly responsible for land degradation. Can degraded land be reclaimed or rejuvenated? To
answer this grave question we have Central Arid Zone Research Area (CAZRA) at Jodhpur
concerned with the conservation of land.
During recent years increase in human activity has led to the degradation of habitat
including cultivated land forests. Mangroves etc. About 50% of the land throughout the
planet is arid with problem of acidity and salinity. Restoration of these areas is a matter
of concern for developed as well as developing countries. However, in sites method are
relatively in efficient. With the advent of biotechnology however a number of opportunities
for ‘recovery of degraded land have arisen through manipulation of biological systems.
Wasteland
Land, which does not give enough economic return or is otherwise useless, can broadly
be termed as wasteland. National Wasteland Development Board (NWDB) in the ministry
or Environment and Forest have defined wasteland as that land which is degraded and is
presently lying unutilized. Further it has classified it into two categories as i) Culturally
wasteland and ii) Non-cultural wasteland. Characteristics features of wasteland can be
summarized as under:
• The land becomes ecologically unstable and unproductive.
• Land that has nearly or completely lost its topsoil.
• Land that has developed toxicity in the zone of roots for the growth of most plants.
Land Reclamation
It is a process of making an uncultivable land fit for cultivation which is then said to
have been reclaimed. Generally it is carried out either by temporary or permanent control.
Temporary Control Includes
1. Ploughing of salt-’surface crust deeply into the soil.
2. Removing surface accumulation from the soil.
3. Neutralizing the effects of certain salts by use of other salts or acids.
Permanent Control Includes
1. Adequate lowering of water table.
2. Satisfactory water infiltration.
3. Leaching excess salts out of the soil.
4. Intelligent management of soil.
Physical Improvements Involves
1. Applying enough water.
2. Keeping drains open and in good repair.
3. Preventing excessive evaporation.
A few biotechnological methods are described below: .
(i) Reforestation — through micro propagation
(ii) Improvement in soil — by mycorrhize
(iii)Improvement of soil — through N2 fixation
(iv) Development of stress tolerant plant through biotechnology manipulation.
(v) Toxic site reclamation through selective engineer microbes.
Reforestations (Micro Propagation)
Ex situ conservation activities have been carried out through establishment of gene
banks. They have become particularly important for the conservation of crop varieties or
Improvement of crops and & a forestation programmes. The UNEP has advocated for in-situ
and ex-situ conservation efforts. However, funds for ex-situ conservation have been enhanced
recently. A special emphasis has been given to a forestation since forest is a good source of
food, fodder, fiber and pulp. Moreover they help in maintaining climatic stability and
biodiversity. It has been shown that degraded lands can be effectively used and restored by
planting forests. Using trees of wide adaptability and productivity for this purpose clonal
propagation method have been prescribed rather than using seeds of uncertain genetic
quality. Clonal micro propagation can be achieved through techniques of tissue culture.
It has been estimated that multiplication state of 100-200 per year is technically possible
for many species towards this objective genotypes capable of growing well on degraded land
have been selected for mass propagation/multiplication.
The clonal multiplication involves 4 steps.
1. Maintaining an aseptic culture.
2. Shoot multiplication using apical meristem or buds.
3. Rooting of in vitro forms shoots.
4. Acclimatization and transfer of micro propagated plantlets to the field.
According to an estimate in 1990 500 million plants of diverse nature were produced
through micro propagation in 60 countries. In New Zealand large number of micro propagation
plantlets – Pine trees (Pinus radiata) are been used and it is estimated that 2 million
plantlets were in the field in the year 1992.
Stress Tolerant Plant
A large number of biotic factors can create stress to the plant as well as animals. The
survival of plant under such stress conditions like deserts marshland saline acidic and
alkaline condition can be manipulated by suitable strategies. Efforts are under-way for
development of plant resistance to such conditions using biotech methods. Cell lines exhibiting
resistance or tolerance to salt stress have been selected in a large number of plant species
and can be used to reclaim degraded land suffering from salinity.
These are as follows:
Brassica sp. Capsicum annum
Cieer arietinum Citrus aurantium
C. sinensis Dacus carota
Nicotiana tobaccum Oryzae sativa
Triticum aeslivium Sapiendus trifoliala
There are several species of trees that exhibit moderate resistance to salinity that can
be used for reclamation of saline soils. These are Prosobis, Spicigera, Beautea monosperma,
Terminalia ballacca. Efforts are being made to understand the basis of salt tolerance and
isolate the gene responsible for this attribute so that salt tolerant plant can be developed
through genetic engineering. Attempts have been made to develop acidic resistant crops.
Man made synthetic crop ‘triticale’ has been found to be suitable in acidic soils, in countries
like: Poland, Kenya. & Mexico, on dry and sandy soils e.g. Brazil, on alkaline and calcareous
soils e.g. Spain, USA, on mineral, deficient & high boron soils.
Methods For Reclaiming Land
1. Reclamation & management of saline and alkaline soils can be done through:
Alkali soils usually contain excessive amounts of sodium and therefore have a poor
physical condition. To be reclaimed these soils must be changed chemically and improved
physically. The chemical changes consist of exchanging calcium for sodium and thus leaching
away the Na salts. Application of PO4 fertilizers is usually recommendable for low phosphorous
containing soils.
2. Reclamation of waterlogged land:
Agricultural land is said to be water logged when its fertility is affected by the height
of water table, due to flooding of root zone of plants, ill-aeration results. They can be made
productive by providing efficient surface drainage and sub-surface drainage:
1. Pipe/tile drains
2. Deep open trenches
3. Reclamation of soils damaged by sea water:
Areas near seacoasts suffer occasional flooding by seawater. In such cases soils
have reclaimed by pumping out the excess salts, water & drainage e.g. Netherlands.
4. Reclamation of mined wasteland:
Mining and its allied works have ravaged the land surface. To reclaim such ravaged
lands species selected should be able to quickly grow and effectively stabilize and improve
the soil. Mixture of grasses rather than woody perennials is preferred.
Reclamation Work In India
In India reclamation of limestone & rock phosphate mines in Dehradun and Mussourie
has been successfully accomplished with the help of Pinus, Ledrus, Acacia sp. The story of
degeneration and regeneration of Jhabua-poor tribal districts of Madhya Pradesh bordering
Gujarat is also satisfactory. It was reclaimed with watershed development in mid 1990′ s
under the Rajiv Gandhi Mission. In 1993, the intervention of a NGO, the Samaj Pragati
Sahyog in Neemkheda, a remote Village in Dewas district of M.P. took a number of watershed
development activities. An area of nearly 300 m2 has been reclaimed in Baiera Village
(Kangra, H.P.) by an old co-operative farming society (1965-66).
Conclusion
All these instances show that the regeneration of the environment is possible with
political will, competent and committed bureaucratic support, people’s participation &
enforcement of stringent laws.
Consumerism and Waste Products
Increase in demand on depleting resources is never-ending and human beings quest to
achieve breakthroughs in technical advancements will never be final. People to satisfy their
wants and lead a more comfortable life relate the concept of consumerism to increased usage
of consumer goods. People easily adapt to disposable life-style as it leads to a cut down on
household chores. The market forces devise such things to sell comfort to people, which
attract people, the most. Soon people realize that comfort has become the necessity of life.
The Indian market trend and culture is fast adapting to the western society where packed
food material and other life supporting commodities are readily available in packed condition.
Market strategies set to work trying new tactics to get consumers buy more. People in turn
make consumption a way of their life, which leads to generation of solid Waste problems.
People consume and throwaway the refuge at an ever-growing rate.
Packed food resource consumption is, in itself a great problem to deal with. We get easy
food supply even in aeroplanes and trains in packed condition. Besides our daily life activities
related to consumption of flour, vegetable, milk, butter, marketing of household goods and
others all takes place through plastic bags, paper bags, tin cans and others. Plastic bags are
non-biodegradable. So when they are thrown away, they create havoc that is potentially
eternal. Municipal reports from Assam and Haryana speak of drains clogged by discarded
plastic bags, backflow in sewage pipes, and disease spreading through pond-like accumulation
of sewage, which also serves as sites of mosquito breeding.
Nations with high standard of living generate more of solid waste than developing
countries. This causes an ever-increasing burden of garbage, which in turn is related to their
disposal problems. Even land filling and other methods of disposal have their own limitations.
We need ample of land to bury, burn or dispose waste. Ash from incineration is also a major
problem because the ash contains lead, cadmium, mercury, and arsenic in various proportions
from batteries, lighting fixtures and pigments. The toxic substances are more concentrated
in the ash than in the original garbage and can lead to water pollution. Case studies shows
that even land beneath landfills get polluted and cause air pollution above the ground and
water pollution below the ground.
The most fundamental way to reduce waste is to prevent it from ever becoming waste.
Another way market operations reduce waste is by making consumer products in concentrated
form. Municipal composting is another source-reduction technique. On an individual level,
we can all attempt to reduce the amount of waste we generate. Every small personal
commitment from each of us could have the cumulative result of a significant magnitude in
reducing the solid waste production.
Residues and Wastes
As man engages in the activities associated with living, wastes are produces, these are
products, which have no apparent useful purpose, or they are of such marginal utility that
recovery is uneconomical. Such products include human, residential, agricultural, commercial
and industrial wastes of all kinds. The continuous removal and safe disposal of these wastes
is essential to the continued existence of any community. These wastes may be solid, liquid
or gaseous. Bodily discharges have historically been considered to be very hazardous to
mankind. Intestinal diseases are readily transmitted where water or food is contaminated
directed or indirectly by human wastes. Such wastes also provide a medium for fly breeding.
Food scraps and waste food constitute garbage. When combined with other household waste,
residential refuse is generated. The organic portion will attract and sustain flies and rats.
Where wastes are water-carried, pollution of water supplies may occur. Commercial and
industrial liquid wastes may contain particulate and chemical pollutants.
Many activities of man-driving an automobile, generating electric power, processing
chemicals and petroleum, manufacturing certain products, disposal of wastes – may result,
if uncontrolled, in the discharge of solid particles and gaseous pollutants to the atmosphere.
Excessive pollution of the air has been cited as a cause of disease and death. In summary,
these wastes, if improperly handled endanger man’s life support systems.
The Environment Protection Act, 1986
(No. 29 of 1986) An Act to provide for the protection and improvement of environment
and for matters connected therewith. Whereas decisions were taken at the United Nations
Conference on the Human Environment held at Stokholm in June 1972, in which India
participated, to take appropriate steps for the protection and improvement of human
environment;
Short Title, Extent and Commencement
1. This Act may be called the Environment (Protection) Act, 1986.
2. It extends to the whole of India.
3. It shall come into force on such date as the Central Government may, by notification
in the Official Gazette, appoint and different dates may be appointed for different
provisions of this Act and for different areas.
The Act clearly states and explain each and every term very precisely like environment,
environmental pollutants, environmental pollution, handling, hazardous substance, occupier,
prescribed.
General Powers of the Central Government
Power of Central Government to take measures to protect and improve environment.
1. Subject to the provisions of this Act, the Central Government shall have the power
to take all such measures, as it deems necessary or expedient for the purpose of
protecting and improving the quality of the environment.
2. Planning and execution of a nationwide programme for the prevention, control and
abatement of environmental pollution;
3. Laying down standards for the quality of environment in its various aspects;
4. Laying down standards for emission or discharge of environmental pollutants from
various sources.
5. Restriction of areas in which any industries, operations or processes or class of
industries, operations or processes shall not be carried out or shall be carried out
subject to certain safeguards;
6. Laying down procedures and safeguards for the handling of hazardous substances;
7. Examination of such manufacturing processes, materials and substances as are
likely to cause environmental pollution;
8. Carrying out and sponsoring investigations and research relating to problems of
environmental pollution;
9. Inspection of any premises, plant, equipment, machinery, manufacturing or other
processes, materials or substances and giving, by order, of such directions touch
authorities, officers or persons as if may consider necessary to take steps for the
prevention, control and abatement of environmental pollution;
10. Preparation of manuals, codes or guides relating to the prevention, control and
abatement of environmental pollution.
Air Pollution Act, 1981
An Act to provide for the prevention, control and abatement of air pollution, for the
establishment, with a view to carrying out the aforesaid purposes, of Boards, for conferring
on and assigning to such Boards powers and functions relating thereto and for matters’
connected therewith. Whereas decisions were taken at the United Nations Conference on
the Human Environment hold in Stockholm in June, 1972, in which India participated, to
take appropriate steps for the preservation of the natural resources of the earth which,
among other things, include the preservation of the quality of air and control of air pollution
and whereas it is considered necessary to implement the decisions aforesaid in so far as they
relate to the preservation of the quality of air and control of air pollution.
Short title, extent and commencement
1. This Act may be called the Air (Prevention and Control of Pollution) Act, 1981.
2. It extends to the whole of India.
3. It shall come into force on such date as the Central Government may, by notification
in the official Gazette, appoint.
The Act clearly states and explain each and every term very precisely air pollutant, air
pollution, approved appliances, approved fuel, automobile, central board, chimney, control
equipment, emission, industrial plant, member, occupier, prescribed, state board.
Water Pollution Act, 1974
An Act to provide for the prevention and control of water pollution and the maintaining
or restoring of wholesomeness of water, for the establishment, with a view to carrying out
the purposes aforesaid, of Boards for the prevention and control of water pollution, for
conferring on and assigning to such Board powers and functions relating thereto and for
matters connected therewith. Whereas it is expedient to provide for the prevention and
control of water pollution and the maintaining or restoring of wholesomeness of water, for
the establishment, with a view to carrying out the purposes aforesaid, of Boards for the
prevention and control of water pollution and for conferring on and assigning to such Boards
powers and functions relating thereto.
Short title, application and commencement
1. This Act may be called the Water (Prevention and Control of Pollution) Act, 1974,
2. It applies in the first instance to the whole of the States of Assam, Bihar, Gujarat,
Haryana, Himachal Pradesh, Jammu and. Kashmir, Karnataka, Kerala, Madhya
Pradesh, Rajasthan, Tripura and West Bengal and the Union Territories; and it
shall apply to such other State which adopts this Act by resolution passed in that
behalf under clause (1) of the article 252 of the Constitution.
3. It shall come into force, at once in the States of Assam, Bihar, Gujarat, Haryana,
Himachal Pradesh, Jammu and Kashmir, Kamataka, Kerala, Madhya Pradesh,
Rajasthan, Tripura and West Bengal and in the Union Territories; and in any other
State which adopted this Act under clause (1) of article 252 of the Constitution on
the date of such adoption and any reference in this Act to the commencement of
this Act shall, in relation to any State or Union Territory, mean the date on which
this Act comes into force in such State of Union territory.
The Act clearly states and explain each and every term very precisely like board,
central board, member, outlet, pollution, prescribed, sewage effluent, sewer, state board,
state government, trade effluent etc.
The Wildlife (Protection) Act, 1972
An Act to provide for the protection of wild animals and birds and for matters connected
therewith or ancillary or incidental thereto.
Short title, extent and commencement
1 This Act may be called the Wild Life (Protection) Act, 1972
2 It extends, in the first instance, to the whole of the States of Andhra Pradesh,
Bihar, Gujarat, Haryana, Himachal Pradesh, Madhya Pradesh, Manipur, Punjab,
Rajasthan, Uttar Pradesh and West Bengal and to all the Union territories; and it
shall also extend to such other State as may adopt this Act by resolution passed
in that behalf in pursuance of CI. (1) of Art. 252 of the Constitution.
It shall come into force in a State of Union territory to which it extends, or may
become extended in future, on such date as the Central Government may, by
notification, appoint, and different dates may be appointed for different provisions
of this Act or for different States or Union territories.
The Act clearly states and explains each and every term very precisely like animal,
animal article, big game, board, captive animal, cattle, chief wild life warden, closed area,
collector, commencement of this act, dealer, director, game reserve, government property,
habitat, hunting, land, license, manufacturer, meat, national park, notification, permit person,
prescribed, sanctuary, small game, special game, state government, taxidermy, trophy,
uncured trophy, vehicle, vermin, weapon, wild animal, wild life, wile life warden.
Forest Conservation Act
India’s Forest Policies
Development of forest is guided by the policies adopted by a nation to manage them.
Scientific forestry was adopted in India since over a century back. Country’s first forest
policy was enunciated in 1894. After the Independence Indian Republic therefore formulated
her National Forest Policy in 1952. The National Commission on Agriculture established in
1970 went into the forestry situation in the country and suggested a need for a new forest
policy, in their Report of 1976. The Constitution of the Independent India placed forests
under the State List of the Seventh Schedule in 1950. The States were vested with the
administration of the forests. The Constitution has recognized the importance of protection
of forests and their improvement. It is stipulated in Article 48-A, that the State shall
endeavourer to protect and improve the environment and to safeguard the forests and
wildlife of the country.
The period between 1950 and today has witnessed large-scale depletion of forests and
attrition of forestlands. Forests lands were cleared and diverted to other uses like agriculture,
industries, hydroelectric projects, settlement of displaced persons and foreign refugees, etc.
This also resulted in diminishing wildlife in the country due to loss of their habitat. Realizing
the importance of forests for the well being of the nation, the Parliament, by the 42nd
Amendment to the Constitution, in 1976, brought Forests and Wildlife on the concurrent list
in Seventh Schedule. In the year 1980, the President of India promulgated the Forest
(Conservation) Ordinance, 1980, which put severe restrictions on de-reservation of forest or
use of forestland for non-forest purposes, without prior approval of the Central Government.
Forests play three important roles in national economy of any country, they are:
(a) protective, (b) productive, and (c) as a source of accessory benefits. This calls for an
effective legislation. The Indian Forest Act, 1927, is in force today for the same purpose.
Similarly a comprehensive legislation for the protection of wildlife and nature is to be found
in the Wildlife (Protection) Act, 1972.
Forest Policy of 1894
Enunciated in 1894 India’s first Forest Policy laid down ‘public benefit’ as the sole
objective of the administration of public forest. The Policy suggested the maintenance of
forests in hilly areas for preservation of climatic and physical conditions and for protection
of cultivated plains below from the divesting action of hill torrents. Forests with valuable
timbers were to be managed on commercial lines. The forests of inferior quality were to be
managed mainly in the interest of local population.
Guiding Principles for Forest Policy
India’s Forest Policy was revised once again in 1988. The main plan of the revised
Forest Policy of 1988 is protection, conservation and development of forests. Its aims are
(i) maintenance of environmental stability through preservation and restoration of ecological
balance, (ii) conservation of natural heritage, (iii) check on soil erosion and denudation in
catchments area of rivers, lakes and reservoir, (iv) check on extension of sand dunes in
desert areas of Rajasthan and along coastal tracts, (v) substantial increase in forest/tree
cover through massive a forestation and social forestry programmes, (vi) steps to meet
requirements of fuel for wood, fodder, minor forest produce and soil timber of rural and
tribal populations, (vii) increase in productivity of forest to meet the national needs; (viii)
encouragement of efficient utilization of forest produce and optimum substitution of wood,
and (ix) steps to create massive people’s participation with involvement of women to achieve
the objectives and minimize pressure on existing forests.
Forest Conservation
The increasing destruction and degradation of forests and tree lands especially in the
Himalayas and other hill areas, is leading to heavy erosion of topsoil, erratic rainfall and
recurring floods. Another area of concern has been degradation of forests due to biotic
pressure. Guidelines have been framed for preparation of working plans and felling in
forests. Some of the salient features are (i) working plans should be up-to-date and stress
conservation (ii

12/05/2019 YamEen Uncategorized

6 Environmental science Social Issues part 1

IntroductionThe term sustainable was development and introduced by the World Commission onEnvironment and Development (The Brundtland Commission), in its seminal report of 1987,Our Common Future. The concept has terrifically worked out in creating public awarenessfor sustaining the planet with better management. The sustainable development has beendefined as “meeting the need of the present generation without compromising the needs offuture generation”. The concept precisely emphasizes upon using the earth resourcesjudiciously and compensating for it in some sense e.g. if cut few trees to support our lives,
we should also implant some new ones at some site. This would result in. maintaining the
earths fine balance between resource consumption and resource generation.
In understanding this concept we very often encounter two terms- sustainable and
development. These are summarized below as:
Sustainable
The literal meaning of sustainability is “that can be maintained” or “keep goal
continuously”. In ecological sense it refers to “conservation of ecological balance by avoiding
depletion of natural resources”. Hence, we can understand it as something, which has got
to do with longevity (long life) of a resource, commodity, species, ecosystem, earth etc.
Development
The literal meaning of development is “the act or instance of growth/advancement”. So
the growth can be of many types viz., growth of education, growth of industry, growth of
population, growth of forests and many other. But what type of growth are we addressing
to? Here we are addressing to one of the most sensitive issue of growing concern ‘about
improving the well-being of human beings. This could be achieved only through compromising
with some of our comforts and luxuries. The generation of comforts and luxuries brings
environment under great pressure. The Nations economic growth should not stand upon the
fragile foundation of earth’s resources. Mahatma Gandhi a great social scientist, rightly
192
CHAPTER
Environmental Science :
6 Social Issues
pointed out that, “The earth provides enough to satisfy everyone’s need, but not everyone’s
greed”.
In the context of economical and technical development the world always had been
better today than yesteryears and will always be better tomorrow than today. But the
condition of environment will always be poorer than before. Hence, the concept of sustainable
development raises certain questions for the present generations to answer. What is our
present? Are we happy with our present? Prospective changes of the magnitude described
above raises fundamental questions about the kind of world we will bequeath to our children
and about the nature and goals of development. The present in which we live is important
as it shapes our future. Nothing much can be done to recover the damages imposed on
nature in the past. But if we shape our surroundings based on environmental ethics and
economically exploit our present environment we would lend a healthier tomorrow to our
children. As we have examined some environmental issues in the previous chapters, we
would commonly agree that human population growth, loss of biodiversity, habitat destruction,
ozone depletion, global climate change, pollution (air, water, noise etc.) and limited food &
energy supply are environmental concerns of global scale. In the past two decades a great
deal of work from researchers, ecologists, environmental scientists, social scientists,
geographers and demographers have build up a very clear picture of what our tomorrow
would be like: Some initiatives have been taken up both at government and non-government
level. Still promising environmental concern at individual level is far lacking beyond
sustainable needs.
Although population growth continues to expand at an unsustainable pace but still
certain countries have achieved a demographic transition to zero population growth. However,
positive signs from developing nations are still absent. We have achieved breakthroughs in
renewable energy sources, agro-forestry schemes and better pollution control advancements.
Increased man awareness, resourcefulness and enterprise will help eliminate poverty and
resource wastage and will make our environment a much better place to live in. Until
environmental concerns do not find space in our heart we would never be able to delicately
handle our surroundings when we are at home or public. We should recognize things at
personal and collective grounds to protect nature and to create a sustainable environment.
Urban Problems Related to Energy
Big cities and towns have always influenced education, religion, commerce,
communication and politics, which have in turn influenced culture and society in various
proportions. Initially only a very limited section of the society lived in cities and towns while
the chief occupation of major population had been fishing, hunting, agriculture and cattle
rearing. However’ Industrial Revolution lead to expansion of cities and town both in size and
power. In developing nations, especially a large segment of society from villages moved to
cities for occupational support (occupational migration). This exactly was the cause of rapid
expansion of cities’ and formation of metropolitans like Delhi, Bombay, Chennai, Bangalore,
Calcutta and others. This ultimately brought into picture the concept of urbanization and
industrializations, which provided many benefits to society, especially to the rich, but also
introduced some evils in it. Here evils referred to were the increasing demand on energy
resources; whose consumption in turn lead to multitude problems of pollution, resource
shortage, diseases and waste disposal. Some of the major urban problems related to energy
are as under:
194 ENVIRONMENTAL SCIENCE
(i) Electricity
Electricity from various sources is a major requirement of expanding cities, towns and
villages. Each and every activity of mans life is now someway related to electricity
consumption. Housing gadgets like mixer-grinder, T.V., computer, music systems, geysers,
fans, lights, A.C.s, microwave, water lifting pump, warm blowers, coolers, etc. form the
essential components of a house. This all together has led to an electricity energy crunch.
It is well known that some part of electricity is lost in transmission and greater part
is stolen. The remainder is simply not enough to support the majority of people in the city
and that’s why the problem of electricity in cities is on the rise. The buildings are empowering
the cities like anything but nowhere we see dams, supplying electrical units, increasing in
number at the same pace. Therefore, what majority of the cities face today is a usual cut
of electricity for a minimum of 6-8 hrs. This makes today’s urban life handicapped. Resourceful
enjoy the resource benefit from the rising generator and inverter culture, which in turn put
pressure on resources and lead to pollution problems.
(ii) Fossil fuels (petroleum, natural gas and coal)
Fossil fuels have always been under a great threat from times immemorial. In the
absence of technological advancements these have served mankind for several years. In this
quest for energy the coal reserves have suffered a lot. With rise in technical know how man
started generating power from nuclear sources, hydroelectric power, wind power etc. But
still these contribute a little. We still depend on thermal power a lot.
(a) Petrol and Diesel: Transport and communication has brought the petroleum reserves
of the world under a great threat. The rise in number of vehicle per year is immense.
To understand the gravity of the problem a glance of metropolitan roads and lanes
is enough. Even the roads and lanes of big cities, small cities and towns are loaded
with two wheelers.
(b) Natural Gas: The common usage of natural gas is in the form of Liquid Petroleum
Gas (LPG). There is a terrific rise in the usage of LPG driven household commodities
with the expanding population. Earlier the LPG usage was only limited to kitchen
for cooking. The advent of technology introduced a numerous household items
making its use like gas geysers, gas heaters, gas fans, gas lanterns etc. In a way
it is serving as a substitute of electricity, which is other reason for increasing
pressure on oil wells/reserves.
(c) Coal: The world population has extracted and used coal reserves thinking as if it
is a never-ending commodity/resource. It has served Sustainable Development,
— Urban Problems,
— Water Conservation and Management,
— Resettlement and Rehabilitation of People,
— Environmental Ethics,
— Global Warning,
— Environment Protection Act,
— Issues involved in Enforcement of Environment Legislation,
ENVIRONMENTAL SCIENCE : SOCIAL ISSUES 195
Millions throughout the ages. Earlier it was primarily used to support kitchens. People
also utilized it for heating stoves/ heaters in colder regions of the world. Later, its usage in
the railways became the chief cause of its rapid exhaustion. Coal reserves are a limited
source of energy now. It should be used judiciously and economically.
(iii) Fuel wood
Fuel wood being used for the ignition of fire is chiefly responsible for the destruction
of impoverished forestlands. Though fuel wood collection to support family daily chores is
allowed in certain parts of the forest generally the outskirts but the greed and dearth
compels women to penetrate deep into the forest. Generally the big cities are characterised
by the absence of forestland at the fringes. But whatever degraded forest is available serve
as a source of fuel wood even in and around urban centres e.g. Dehradun is a well developed
city, but in its fringes we can still see women and children carrying loads of fuel wood.
Water Conservation
We could save as much as half of the water we now use for domestic purposes without
great sacrifice or serious changes in our lifestyles. Simple steps, such as taking shorter
showers, stopping leaks, and washing cars, dishes, and clothes as efficiently as possible, can
go a long way toward forestalling the water shortages that many authorities predict. Isn’t
it better to adapt to more conservative uses now when we have a choice than to be forced
to do it by scarcity in the future?
Rain Water Harvesting
Water is commonly taken for granted as nature’s gift. Often it is used wastefully in
agriculture, but industry and people pollute and poison available water supplies at an
alarming rate. Water problems arise from increasing demands generated by rapid population
growth; urbanization, industrialization and irrigation for additional food production. In many
areas excessive pumping of groundwater not only brings down water quality, but also depletes
it this affects’ sustainability. The ‘capacity of irrigation tanks numbering about five lakh in
the country is shrinking due to situation and encroachment. Scarcity is noticed even in high
rainfall areas like Cherrapunji (Assam), Western Ghats and Kerala. This is due to improper
management and poor conservation of rainwater.
India’s water potential is substantial but the scarcity is felt everywhere even for drinking.
This is because the country’s water policy and management is not very specific and
implementation is poor. Total rain in the country is about 400 M hm (million hectare
meters). The runoff in the rivers is estimated at 186 M ha. Further the utilizable groundwater
is calculated as 40 M hm. However, the utilizable quantity is about 110-115 M hm (70 M
hm from surface and 40 M hm from groundwater). To meet the relentless increase in
demand for water for various purposes and to achieve the goal of optimal use and to get the
maximum benefits, it is necessary to make water resource development holistic through a
comprehensive integrated river basin planning and management. This can be done only if
a wide range of disciplines are involved. Wastage of water due to leakage in pipes and
unattended repairs results in about 30-40 per cent water resource lost.
The landscape watershed units can be effectively subdivided into discrete hydrological
units. Since the watersheds are spatially laid from ridge to valley, they most efficiently
conserve land and water resources and help secure water availability throughout the growing
196 ENVIRONMENTAL SCIENCE
season. The land area of the watershed drains into a common point. Hence, the drainage
water can be easily stored in above -ground storage structures for recycling during droughts
or for growing an additional crop. Rain fed agriculture research and development has been
dominated by the concept of high yields for decades. It arose from the scientific principles
developed for the ‘green revolution’ high input, high-output technologies. Fatigue and cracks
are now developing in the green revolution areas. For rain fed agriculture, an area-based
development through watershed management provides an excellent framework for sustaining
semi-arid tropical ecologies. Also the landscape watershed units focus on the maintenance
of managed biodiversity through diversified cropping systems. It is significant to note that
a broad range of baseline information on watershed-based soil and water conservation
technologies already exists. A study commissioned by the National Institute of Agricultural
Extension Management, Hyderabad, showed that if the watershed technology is to succeed
it must be specific to natural endowments of the location; it must be built on indigenous
knowledge; it should be based on people’s participation; it must be equitable in sharing of
costs and benefits, and village-based institutions must be put-in-place right from inception
of the project.
Watershed Management
It was suggested that, rather than allowing residential, commercial, or industrial
development on flood plains, these areas should be reserved for water storage, aquifer
recharge, wildlife habitat, and agriculture. Sound farming and forestry practices can reduce
runoff. Retaining crop residue on fields reduces flooding, and minimizing. Ploughing and
forest cutting on steep slopes protects watersheds. Wetlands conservation preserves natural
water storage capacity and aquifer recharge zones. A river fed by marshes and wet meadows
tend to run consistently clear and steady rather than in violent floods.
A series of small dams on tributary streams can hold backwater before it becomes a
great flood. Ponds formed by these dams provide useful wildlife habitat and stock-watering
facilities. They also catch soil where it could be returned to the fields. Small dams can be
built with simple equipment and local labour; eliminating the need for massive construction
projects and huge dams. Watershed-based frame for rain fed agriculture provides uncommon
opportunities for achieving sustainable food and nutritional security. It is time that the
watershed development agenda is considered a programme for-the masses.
Resettlement and Rehabilitation of People
“Land for land” is a better policy than cash settlement. Even in implementing this
policy, the land is not given in the command area in most cases, forestland is either cleared
on waste fallow land given without any provision for developing the land or for the supply
of necessary inputs; a village is broken up and families dispersed; villagers are usually left
to buy private land, take loans from the government, which puts poor villagers at a
disadvantage- land prices in neighboring villages shoot up steeply if the government takes
up resettlement; the villagers are resettled in distant places, sometimes in a totally alien
environment and culture, thus creating insurmountable adjustment problems. Oustees from
Pong dam in Himachal Pradesh were settled in Anupgarh in Rajasthan, bordering on Pakistan.
The people were generally left to fend for themselves. Arrangements for drinking water,
dispensaries, schools, village roads or drainage of the rehabilitation sites are only completed
years later. In the case of the Ukai Dam in Gujarat, resettlement work was undertaken by
ENVIRONMENTAL SCIENCE : SOCIAL ISSUES 197
the ‘Ukai Nav Nirman Samity. Even so, out of a total of 18,500 affected families, only 3500
families could be resettled.
People who could previously barely manage to survive in their traditional environment
are uprooted as a result. The objectives of rehabilitation should be:
1. The people displaced should get an appropriate share in the fruits of development.
2. Creating new settlements with their own environment should rehabilitate them.
3. Removal of poverty should also be an objective of the rehabilitation policy and
therefore some land to all.
4. Oustees (even the landless) should be given assurance of employment.
5. While dealing with tribal one should also keep in mind the following five principles
of tribal-development accepted during Jawaharlal Nehru’s era as ‘tribal panchsheel.’
6. Tribal should develop along the lines of their own genius and we should avoid
imposing anything on them.
7. We should try to encourage their own traditional arts and culture in every way.
8. Resettlement should be in the neighborhood of their own environment. If
resettlement is not possible in the command area, top priority should be given to
the development of irrigation facilities and supply of basic inputs for agriculture;
drinking water, wells, grazing grounds for cattle schools for the children, primary
health care units and other amenities should be arranged.
9. In partly affected village, villagers should be given the option of shifting out with
others with the same compensation as available to evacuees.
10. Training facilities should be set up to upgrade the skills of affected people and
reservation in jobs should be made for the willing adults among the evacuees.
11. Special attention should be given to the rehabilitation of artisans and village crafts
people.
12. Villagers should be taken into confidence at every stage or implementation and
they should be educated, through open meetings and discussion about the legalities
of the Land Acquisition Act and other rehabilitation provisions.
13. The aid of voluntary agencies planning and implementation programme.
Rehabilitation Problem
Involuntary displacement of human population is always traumatic. Irrespective of the
causes leading to such migrations the degree of suffering experienced by such people simply
cannot be quantified in money values, and even in words it can be described only inadequately.
But, unfortunately, ousting of people likely to be submerged under irrigation or hydel power
dams is a classic case where hardships are imposed on people in spite of the ‘pro-people’
laws and policies proclaimed by the Government. Below is a critique of the Tehri Dam
Rehabilitation.
Compensatory Land
The project authorities commenced the Scheme by allocating 2767 acre of land in the
Dehra Dun area, which was already reeling under severe pressure from tourism, limestone
quarrying and urban expansion.

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12/05/2019 YamEen Uncategorized

5 Pollution and its Factors part 4

Disaster Management
Loss of life and property due to natural disasters like tropical cyclones, floods, droughts,
tornadoes, earthquakes, volcanic eruptions etc, is very large. Fortunately warning facilities
are available today and by mitigation measures, loss of lives and properties can be minimized.
National Meteorological Services of the world to provide warnings to the public for some of
the weather related natural disasters. It is not possible to forecast a long period ahead
precisely when and where a dangerous natural phenomenon will take place. While natural
disasters cannot be prevented, taking proper long-term and short-term disaster mitigation
measures can minimize the loss of life and property.
Some common disasters known to occur in our country are as under:
Floods
Floods are defined as a relatively high flow of water discharged from river and stream
network, which sets the riverbank margins to overflow and lead to the inundation of low
land areas surrounding the riverbed. It is essentially a physical phenomenon. Floods arise
from abnormally heavy rains, dam failures, snow melts, river blockages. Flood disasters
rank second only to droughts in the total number of people affected worldwide.
Types of Floods
Floods can be classified into three categories as under:
(i) River floods
Rivers get charged due to heavy rains over large catchments areas or by melting of
snow or sometimes both especially in the mountainous tracts. The floods take place in river
systems with tributaries that may drain into large geographic areas and encompass many
independent river basins. Amount of flooding depends on moisture in the soil, vegetation
cover, and depth of snow and size of catchments basin.
(ii) Coastal floods
Coastal flooding is associated with tropical cyclones/ harsh winds arising at the ocean
surface. Coastal floods are often aggravated by wind induced storm surges along the coastline.
Sea and ocean ‘water floods the inland coasts affecting kilometers of tracts. Ocean tides,
storm surges or tsunamis play a definite role. Prolonged and indefinite rains in the rainy
season marked from June-September results in extreme flood in coastal river basins.
(iii) Flash floods
These floods occur within six’ hours of the beginning of rainfall and; are characterized
with rising clouds, thunderstorms and tropical cyclones. These result from runoff from a
torrential downpour, particularly if the catchments slope is unable to absorb and hold a
significant part of water. Other causes of flash floods include dam failure, sudden break up
of glaciers etc. These offer potential threats in the areas where the terrain is steep, surface
runoff is high, water flows through canyons and where severe rainstorms are likely.
General Characteristics of Floods
1. Man made structures and forest vegetation exhibits different levels of tolerance
towards effects of floods.
2. Intensity of damage is governed by the time interval of standing floodwaters.
3. High velocity of running water may uproot or weaken foundations of buildings.
4. Rate of rise and discharge of a river is important as a basis for flood control.
5. Frequency of occurrence estimated over a length of period would determine the
kind of activities the flood plain should be put to.
6. Generally the rainy season is characterized by the floods during which agricultural
economy suffers a huge loss.
Effects of Floods
1. Rising water, erosion and the force damages the residential and commercial building.
They are dangerous for villages lying in the coastal areas as it sweeps away
everything, which comes into its path. In mountainous areas it is the chief cause
of landslides.
2. Fisherman, local people, cattle, animals and vegetation suffer a great loss of life
and property. Most of the deaths are reported to be from drowning.
3. Fresh water supplies by all sources are nearly destroyed and contaminated hence
the areas falling under its impact bear a great risk of suffering from water borne
diseases.
4. The destruction of food and fodder crops result in acute food shortage.
5. Floods also make soil infertile, as the topsoil is lost due to erosional activity.
6. Floods are also known to preserve, wetlands and recharge ground water.
Flood Control
1. Depth and width of the riverbed could be increased as its capacity to carry larger
loads increases manifold and thus reduce the area of the flood plain.
2. A network of canals can be established from the river systems, which generally
leads to floods. This would also benefit the agricultural economy/ section. Care
must be taken in the design and construction because of the possible environmental
impact and necessary safety features.
3. Reservoirs should be made for storing floodwater and releasing them at manageable
rates. This would require careful engineering. Dams, and reservoirs would further
lead to generation of resources.
4. Newly constructed residential as well commercial buildings should have foundations,
which are strong enough to respond to flood conditions.
5. Rivers and streambeds should be stabilized with stone, masonry or vegetation at
the banks. This should strictly be followed where rivers pass through cities, specially
near bridges.
Post Disaster Requirements
The initial response to flooding authorities/community should include:
Search and Rescue operations, water provision,
Medical assistance, Disaster epidemiological surveillance assessment, food and
and temporary shelter.
The secondary response should include:
Reconstruction of houses, equipment and tools, supply
Creation of employment, of animals, and assist with
Assistance to farmers, recovery of small business
Distribution of farm and fisheries.
Flood Problem In India
The nature of flood problem varies from one river system to another. Two great river
systems are discussed below considering the flood problems in India:
Brahmputra River
The main problem of flooding in the northeastern region arises from the Brahmaputra
river and its tributaries. The river in monsoon season overflows its banks and causes a great
damage to life and property both. Several times it has affected Kaziranga wildlife sanctuary
where rhinoceros population died due to rising floods. In recent years, the erosion along the
banks of the Brahmputra has assumed serious proportions. The rivers also carry considerable
amount of silt and have a tendency to change its course.
Ganga River System
In this region the northern tributaries of the Ganga, namely the Rapti, the Sharada,
the Ghaghra and the Gandak cause extensive flooding along their banks. Drainage congestion
is confined to the northwestern parts of U.P., Meerut, Mathura and Agra suffers the most.
Bihar suffers a considerable amount of damage due to the flooding of the Burhi Gandak, the
Baghirati, the Kamla Balan, the Kosi and the Mahananda. In addition to the crop submergence
the area experiences traffic dislocation also. In the Bengal region Baghirati, the Ajoy and
the Damodar cause extensive flooding. Here the tidal effect of Bay of Bengal also plays a
role in flooding. In Delhi and Haryana it is the Yamuna, the biggest tributary of the Ganga,
which causes a marginal amount of flooding. Most of these flooding regions suffer from
inadequate channel capacity as well as regulation of river water flow in these channels.
Earthquakes and Seismology
An earthquake is a major demonstration of the power of the tectonic forces caused by
endogenetic thermal conditions of the interior of the earth. An earthquake is a motion of the
ground surface, ranging from a faint tremor to a wild motion capable of shaking buildings
apart and causing gaping fissures to open in the ground. The Richter scale devised by
Charles F. Richter in 1935 measures the magnitude or intensity of energy released by an
earthquake. Good Friday Earthquake of March 27, 1964 in Alaska (USA) measuring 8.4 to
8.6 on Richter scale is among the greatest earthquakes of the world ever recorded.
The science that studies the behaviour and patterns of seismic waves is called seismology.
The place of origin of an earthquake is called focus, which is always hidden inside the earth,
but its depth varies from place to place. The place of the origin of an earthquake is called
‘focus’ which is always hidden inside the earth. The deepest earthquake may have its focus
at a depth of even 700 km below the ground surface. Major Himalayan earthquakes, such
as the Bihar-Nepal earth quake of August 2, 1988, have their focus around 20-30 km deep.
The place on the ground surface, which is perpendicular to the buried ‘focus’ or ‘hypocenter’
recording the seismic waves for the first time is called ‘epicenter’. The waves generated by
an earthquake are called ‘seismic waves’ which are recorded by an instrument called
seismograph. The lines joining the places of equal intensity of seismic waves on the maps
are called is oseismallines.
Causes of Earthquakes
Earthquakes are caused mainly due to disequilibria in any part of the crust of the
earth. A number of causes have been assigned to cause disequilibria in the earth’s crust such
as volcanic eruptions, faulting and folding, gaseous expansion and contraction inside the
earth, hydrostatic pressure of man-made water bodies like reservoirs and lakes, and plate
movements.
(1) Vulcan City
Volcanic activity is considered to be one of the major causes of earthquakes. Vulcan city
and seismic events are so intimately related to each other that they become cause and effect
for each other. Earthquakes follow each volcanic eruption and many of the severe earthquakes
cause volcanic eruptions. The explosive violent gases during the process of Vulcan city try
to escape upward and hence they push the crystal surface from below with great force and
thus is’ caused severe earth tremors of high magnitude.
(2) Faulting and Elastic Rebound Theory
The horizontal and vertical movements caused by end genetic forces result in the
formation of faults and folds which in turn cause isocratic disequilibria in the crystal rocks
which ultimately causes earthquakes of varying magnitudes depending on the nature and
magnitude of dislocation of rock blocks caused by faulting and folding. The 1950 earthquake
of Assam was believed to have been caused due to disequilibria in crystal rocks;
(3) Hydrostatic Pressure and Anthropogenic Causes
Certain human activities such as pumping of ground water and oil, deep underground
mining, blasting of rocks by dynamites for constructional purposes, nuclear explosion, storage
of huge volume of water in big reservoirs etc. also cause earth tremors of serious consequences.
The introduction of additional load through the construction of large dams and impounding
of enormous volume of water in big reservoirs behind the dams cause disequilibria of adjusted
rocks below the reservoirs.
(4) Plate Tectonic Theory
The earth is composed of solid and moving plates having either continental crust or
oceanic crust or even both continental oceanic crusts. The earth’s crust consists of 6 major
plates (Eurasian plate, American plate, African plate, Indian plate, Pacific plate and Antarctic
plate) and 20 minor plates. These plates are constantly moving in relation to each other due
to thermal convective currents originating deep within the earth. All sorts of disequilibria
are caused due to different types of plate motions and consequently earthquakes of varying
magnitudes are caused.
CLASSIFICATION OF EARTHQUAKES
Each earthquake differs from the other and thus it becomes difficult to classify all the
earthquakes into certain categories.
(1) Classification on the Basis of Causative Factors
(A) Natural Earthquakes are those, which are caused by natural processes i.e. due
to end genetic forces. These are further divided into four subcategories.
(i) Volcanic Earthquakes are caused due to volcanic eruptions of explosive
and fissure types and are confined to volcanic areas. Severe earthquake
caused by violent explosions of Etna volcano in 1968.
(ii) Tectonic Earthquakes are caused due to dislocation of rock blocks during
faulting activity. Such earthquake is very severe and disastrous i.e. 1906
earthquake of California (USA).
(iii) Isostatic Earthquakes are triggered due to sudden disturbance in the
Isostatic balance at regional scale due to imbalance in the geological processes.
(iv) Plutonic Earthquakes are in fact, deep focus earthquakes, which occur at
greater depths.
(B) Anthropogenic Earthquakes are caused by human activities such as pumping of
water and mineral oil from underground aquifers. and oil reserves respectively,
deep underground mining, blasting of rocks by dynamites for constructional purposes
e.g. Koyna earthquake of Maharashtra of 1967 due to Koyna reservoir etc.
(2) Classification on the basis of Focus
On the basis of the depths of their foci these have been divided into 3 types.
(i) Moderate Earthquake: Foci are located at the depths between 0-50 km.
(ii) Intermediate Earthquake: Foci at the depths between 50-250 km.
(iii) Deep Focus Earthquake: Foci at the depths between 250-700 km.
Classification on the basis of Human casualties
(i) Moderately Hazardous Earthquakes: If deaths of human range below 50,000
due to seismic tremors e.g. Tabas earthquake of Iran 1978 A.D. (death toll 25,000).
(ii) Highly Hazardous Earthquakes: If deaths of human range between 51,000-
1,00,000 due to seismic tremors e.g. in 1935, Quetta, Baluchistan, (death toll
60,000).
(iii) Most Hazardous Earthquakes: If deaths of human casualties are above 1,00,000
mark e.g., in 1976 Tang-Shan, China (death toll 7,50,000).
World Distribution of Earthquakes
Earthquakes are, in fact associated with the weaker and are statically distributed areas
of the world. Most of the world earthquakes occur in the zones of young folded mountains,
the zones of faulting and fracturing, the junction of continental and oceanic margins, the
zones of active volcanoes and along the different plate boundaries. The world map of the
distribution of earthquakes prepared by seismologists show the occurrence of earthquakes
along the following belts.
(i) Circum-Pacific Belt: surrounding the Pacific Ocean.
(ii) Mid-Continental Belt: representing epicenters located along the Alpine-Himalayan
Chains of Eurasia and northern Africa and epicenters of East African Fault zones.
(iii) Mid Atlantic Belt: representing the earthquakes located along the mid-Atlantic
Ridge-and its offshoots.
Effects of Earthquake hazardous
Earthquakes and their hazards are determined on the basis of the magnitude of seismic
intensity as determined by Richter scale but are decided in the basis of quantum of damages
done by a specific earthquake to human lives and property.
(i) Landslides
Weaker landmasses and tectonically sensitive land margins cause landslides and debris
falls, which damage settlements and transport systems on the lower slope segments.
(ii) Damage to Life and property
Structures such as buildings, roads, rails, factories, dams, bridges suffer a huge damage
thus causing a heavy loss of human life and property both. The vibrations of earthquakes
last longer and the amplitudes of seismic waves are greater artificially in filled and leveled
depressions, swamp deposits etc. than in the structures of consolidated materials and bedrocks.
Two major earthquakes of Bihar-Nepal border in 1934 and 1988 explain the impact of
earthquake disasters on human structures and human lives. The damage caused by the
Bihar earthquake of 15 January 1934, measuring 8.4 on Richter scale, include 10,700 human
deaths, landslides and slumping in an area of 250 km length and 60 km width, ruptures and
faults in the ground surface etc.
(iii) Damages to Government Infrastructure
Cities and towns are worst affected due to large concentration of human population,
commercial complexes and residential areas. Due to collapse of large buildings there is
greater loss of life and property. Due to collapse of buildings ground water pipes are bent
and damaged thus water supply is disrupted, electric and telephone poles are uprooted and
there is total disruption of power and communication. Other side effects are collapsed sewer
system causing epidemics, roadblocks etc.
(iv) Fire Hazard
Earthquakes strongly shake the buildings and thus strong oscillations cause severe
fires in houses, mines and factories because of overturning of cooking gas cylinders, contact
of live electric wires, churning of blast furnaces, displacement of other electric and firerelated appliances.
(v) Landmass Deformation
Severe earth tremors and resultant, vibrations caused by severe earthquakes result in
the deformation of ground surface because of crusts and troughs in the ground surface and
faulting activity.
(vi) Flash Floods
Strong seismic events result in the damages of dams and cause severe flash floods.
Severe floods are also caused because of blocking of water flow of rivers due to rock blocks
and debris produced by severe tremors on the hill slopes facing the river valleys.
(vii) Tsunamis
The seismic waves, caused by the earthquakes traveling through seawater, generate
high sea waves and cause great loss of life and property. Since the pacific Ocean is girdled
by the earthquakes and volcanoes tsunamis are more common in the pacific with a minimum
frequency of 2 tsunamis per year.
A CASE STUDY
U.P. Earthquake of 1991
A severe earthquake occurred in Garhwal region of Uttar Pradesh on 20th Oct. 1991.
Intensive tremors were felt at 2.53 a.m., which lasted for about 45 seconds. The magnitude
of earthquake was measured 6.6 on Richter scale and its epicenter was at Angola, a place
near Uttarkashi, Mild tremors are a regular feature of the area. The worst affected areas
have been in the district of Uttarkashi, Tehri Garhwal and Chamoli while it also caused
sizeable damage in the districts of Dehradun, Pauri Garhwal and Nainital. The roads and
bridges are the chief means of communication in hill region, which underwent heavy damage.
The economy of such places is based on tourism to a great extent, which suffered a great
set back. The overhead drinking tanks and pipelines had developed cracks. Sources of
drinking water had been damaged. The earthquake caused intensive damage to the building
of various government departments, Forest, Home, Finance and Rural Development.
Cyclones
Cyclones are the centers of low pressure surrounded by closed isobars having increasing
pressure outward and closed air circulation from outside towards the central low pressure
in such a way that air blows inward in anticlockwise on northern hemisphere and clockwise
in southern hemisphere. They range in shape from circular, elliptical to V shape. From
locational viewpoint cyclones are classified into two principal types e.g. i) extra-tropical
cyclones/temperate cyclones ii) tropical cyclones.
(I) Temperate Cyclones
Temperate cyclones are atmospheric disturbances having low pressure in the centers
produced in the middle latitudes characterized by converging and rising air, cloudiness and
precipitation. They are formed in the regions extending between 350- 65″ latitudes in both
hemispheres due to convergence of two contrasting air masses e.g. After their formation
temperate cyclones move in easterly direction under the influence of westerly winds and
control the weather conditions in the middle latitudes.
(i) Shape, Size and Speed
Temperate cyclones are of different shapes e.g. circular, semi-circular, elliptical, elongated
or V, but all of them are characterized by low pressure in their centres and closed isobars.
The pressure difference between the centre and periphery is about 10-35 mb. It means that
pressure increases from the centre towards outer margin. Average large diameter of an
ideal cyclone is about t 900 km while short diameter measures t 000 km. The temperate
cyclones move eastward under the influence of westerly winds with average velocity of 32
km per hour in summer and 48 km per hour in winters.
N.W. Quadrant N.E . Q uadrant
Cold front
S.W. Q uadrant
S.E. Q uadrant
Figure 5.1: A generalized temperate cyclone in northern hemisphere.
(ii) Wind Systems
Since there is low pressure in the centre of temperate cyclone and air pressure increases
outward and hence winds blow from the periphery towards the centre but these winds do
not reach the centre straight rather they cut the isobars at the angle of 20° to 400 due to
friction and Coriolis force and thus wind direction becomes anticlockwise in the northern
hemisphere and clockwise in the southern hemisphere. Since temperate cyclones are formed
due to convergence of two contrasting air masses and hence it is natural that there are
variations in the nature and direction of winds in different parts of the cyclones.
(iii) Temperature
Different temperatures are noted in different parts of temperate cyclones because of
their origin due to convergence of two thermally contrasting air masses. The southern part
of cyclone records higher temperature because of the dominance of warm air while the
north-eastern, northern and north-western parts record low temperature because of the
dominance of cold polar air mass. The western part records lowest temperature.
(iv) Source Regions and Tracks of Movement
The areas frequented by temperate cyclones mostly lie in the middle and high latitudes
extending between 350-650 latitudes in both the hemispheres. These cyclones move, on an
average, in easterly direction. (1) Cyclones after originating in the north Pacific off the
north-east and eastern coasts of Asia move in easterly and north-easterly direction towards
the Gulf of Alaska and ultimately merge with Aleutian Lows from where they follow southerly
direction and reach as far south as southern California. The cyclones moving inland dissipate
and are occluded at the windward western slopes of the Rocky Mountains.
(v) Origin of Temperate Cyclones
Though the formation and development of temperate cyclones is a quick process but it
passes through a series of successive stages. The period of a cyclone from its inception
(cyclogenesis) to its termination (proteolysis or occlusion) is called the ‘life cycle of cyclone’;
which is completed through six successive stages.
(a) The first stage involves the convergence of two air masses of contrasting physical
properties and directions. Initially, the air mass (warm and cold) move parallel to
each other and a stationary front is formed. This is called initial stage.
(b) The second stage is also called as ‘incipient stage’, during which the warm and
cold air masses penetrate into the territories of each other and thus a wave-like
front is formed.
(c) Third stage: This is the mature stage when the cyclone is fully developed and
isobars become almost circular.
(d) Fourth stage: Warm sector is narrowed in extent due to the advancement of cold
front than warm front, as cold front comes nearer to warm front.
(e) Fifth stage: Starts with the occlusion of cyclone when the advancing cold front
finally overtakes the warm front and an occluded front is formed.
(f) Sixth stage: Warm sector completely disappears, occluded front is eliminated and
ultimately cyclone dies’ out.
(II) Tropical Cyclones
(i) General Characteristics
Cyclones developed in the regions lying between the tropics of Capricorn and Cancer
are called Tropical Cyclones which are not regular and uniform like extra tropical or temperate
cyclones. There are numerous forms of these cyclones, which vary considerably in shape,
size, velocity and weather conditions. The weather conditions of low latitudes mainly rainfall
regimes are largely controlled by Tropical Cyclones.
(a) Size of tropical cyclones varies considerably. On an average their diameters range
between 80 km and 300 km.
(b) Weak cyclones move at the speed of about 32 km per hour while hurricanes attain
the velocity of 180 km per hour or more.
(c) Tropical cyclones become more vigorous over the oceans but become weak and
feeble while moving over land areas. This is why these cyclones affect only the
coastal areas e.g. Tamil Nadu, Orissa and West Bengal coasts of India.
(d) The centre of the cyclone is characterized by extremely low pressure.
(e) Tropical cyclones are not characterized by temperature variations in their different
parts because they do not have different fronts.
(f) There are no different rainfall cells hence each part of the cyclones yields rainfall.
(g) Tropical cyclones are not always mobile. Normally, they move from east to west
under the influence of trade winds
(h) Tropical cyclones are confined to a particular period of the year (summer season).
(ii) Types of Tropical Cyclones
Generally they are divided into 4 major types
(a) Tropical disturbances or easterly waves
(b) Tropical depressions
(c) Tropical storms
(d) Hurricanes or typhoons
(iii) Origin of Tropical Cyclones
On an average, tropical cyclones are formed due to development of low pressure of
thermal origin. They develop when the following requirements are fulfilled:
(a) There should be continuous supply of abundant warm and moist air. Tropical
cyclones originate over warm oceans having surface temperature of 27°C.
(b) Higher value of Coriolis force is required for the origin of these cyclones.
(c) They are associated with inter-tropical convergence (lTC), which extends from 50
-300N latitudes during summer season.
(d) There should be anti-cyclonic circulation at the height of 9000 to 15000 m above the
surface disturbance.
(iv) Distribution of Tropical Cyclones
There are 6 major regions of the tropical cyclones e.g. (1) West Indies, Gulf of Mexico,
and Caribbean Sea. (2) Western North Pacific Ocean including Philippines, Islands, China
Sea, and Japanese Islands. (3) Arabian Sea and Bay of Bengal. (4) Eastern Pacific coastal
region off Mexico and Central America. (5) South Indian Ocean of Madagascar (Malagasi),
and (6) Western South Pacific Ocean, in the region of Samoa and Fiji Island and the east
and north coasts of Australia.
(v) Environmental Impact of Tropical Cyclones
Tropical cyclones are very severe disastrous natural hazards which inflict heavy loss to
human lives and property in terms of destruction of buildings, transport systems, water and
power supply systems, disruption of communication system, destruction of standing
agricultural crops, domestic and wild animals, natural vegetation, private and public
institutions etc. Through damages caused by high velocity winds, floods and storm surges.
ANTICYCLONES
General Characteristics
Surrounded by circular isobars anticyclone is such a wind system which has highest air
pressure at the centre and lowest at the outer margin and winds blow from the centre
outward in clockwise direction in the northern hemisphere and anticlockwise in the southern
hemisphere fig.13. Thus, anticyclones are high-pressure systems and more common in the
subtropical high pressure belts but are practically absent in the equatorial regions.
Anticyclones were classified into (i) warm anticyclones, and (ii) cold anticyclones by
Hanzilk in 1909.
They are characterized by the following properties.
(1) They are usually circular in shape. The difference of pressure between the centre
and periphery of anticyclone ranges between 10-20 mb.
(2) They are much larger in size and area than temperate cyclones.
(3) Anticyclones follow cyclones. They move very sluggishly. The average velocity of
anticyclones is 30-50 km per hour.
(4) Winds descend from above at the centre and thus weather becomes clear and rain
less because the descending winds cause atmospheric stability.
(5) Temperature in anticyclones depends on weather, nature of air mass and humidity
in the air.
(6) Anticyclones do not have fronts.
1. Wind Systems and Temperature
Wind system is not fully developed in anticyclones because of weak pressure gradient.
On an average, wind circulation is of divergent system wherein winds spread in all directions
from high-pressure centre to low-pressure periphery. The winds are very much sluggish in
the rear portion in comparison to the front portion. The centre is characterized by light
breeze.
These arise due to the descent of either polar cold air mass or warm tropical air mass.
Cold anticyclones are associated with extremely low temperature and they cause cold waves
during winter season but when they come in summer season, weather becomes pleasant.
2. Shapes and Size
Anticyclones are generally of circular shape but are very large in size. They become so
large in size that their diameters become 9,000 km.
3. Weather ConditionsGenerally, anticyclones are rainless and sky is free of clouds because of the fact thatdescending air in the centre of anticyclone is warmed up at dry adiabatic rate due tosubsidence. This causes rise in temperature, which reduces normal lapse rate of temperature,with the result the stability of air increases resulting into marked increase in the aridity of
air. This is why anticyclones are indicative of dry weather.
4. Landslides
Among physiographic units, the two northern units of the Greater Himalayas (7500-
8500m), and the Inner Himalayas (Trans-Himalayan zone), an intervening system of high
plateau and valleys lying between the two great mountain ranges, are considered along with
middle mountains, the traditional centres of population. The upper northern section of these
middle mountains remains largely’ under upper montane forest (2900-4000 m), below which
is the belt of intensive agriculture. Lithology is highly varied, including sedimentary,
metamorphism, and granites. However, there are extensive areas of phyllites and schists;
these are deeply weathered and the prevailing steep slopes render them highly susceptible
to erosion and slope failure (mostly through landslides). Presently, according to gross yet
reliable estimate, the landslides occupy about 1% of land surface in only five central districts
of Himachal Pradesh. They have a total volume of more than 2.2 x 106 m3 and a mean age
of 6.5 years. This helps to evaluate the denudation rate, which is about 12 mm/year (all
erosive processes). Landslides have about 2.5-mm/ year denudation rates. One of the main
causes of landslides is road construction.
Suggestions
Various studies indicate that for each linear kilometer of mountain road, 10 small to
medium landslides occur. Prior to the 1962 border war with China, the Himalayan section
in India was in most parts accessible only on foot. The shock of the Chinese military
presence, the three India-Pakistan wars of 1947, 1965, and 1971, the continued border
tensions (especially along the Kashmir ceasefire line), and several other problems led to
accelerated construction of up to 10,000 km of highways and connecting roads. The poor
alignment and ill-considered design are causing a total soil loss of 0.199 t of sediment per
linear meter of road per annum. Valdiya (1973) indicated that during the construction phase
an average kilometer of road requires the removal of 40,000-80,000 m3 of debris. These
enormous volumes are dumped on the roadsides and damage ecologically fragile slopes by
depriving them of natural vegetation and at times destroy the terraces.
QUESTIONS
1. Write the definition of pollution in your own words and also explain the causes of pollution.
2. Explain the types of pollution. Write the precautions to minimize the pollutions (air, water,
social, marine, noise).
3. What is social water management? Explain.
4. Explain the role of an individual in prevention of pollution and how it is possible?
5. How we can conduct the pollution case study in a particular area and also explain the
disaster management?
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12/05/2019 YamEen Uncategorized

5 Pollution and its Factors part 3

Effect of Noise Pollution
1. Constant noise affects a man physically and mentally. Physical effects include
blood vessels to contract, skin to become pale, muscles to constrict and rise in blood
pressure leading to tension and nervousness.
2. High intensity sound emitted by industrial plants, bottling machines, supersonic
aircrafts, when continued for long periods of time not only disturbs but also
permanently damages hearing.
3. Offices, industries and crowded places where constant noise prevails can produce
temper tantrums, headaches, fatigue and nausea.
4. Loud and sudden noise affect the brain. Intermittent noise leads higher incidence
of psychiatric illness and also a danger to health of pregnant mothers and small
infants.
5. Noise has harmful effects on nonliving materials too, e.g. cracks develop under the
stress of explosive sound.
Control of Noise Pollution
Following methods can control noise pollution:
1. Limited use of loudspeakers and amplifiers.
2. Excursing control over noise producing vehicles.
3. Industrial workers should be provided with ear plugs.
4. Delocalisation of noisy industries far away from dwelling units.
5. Within a radius of 10 miles of airport, no buildings or factories should be allowed.
6. Plants and trees should be planted all around the hospitals, libraries and schools
and colleges.
7. Personal protection against noise can be taken by using, cotton plugs in the ear.
Radiation
The radiations from the atomic blasts cause several health hazards. The radiations
carry high energy and remove electrons from atoms and attach them to other atoms producing
positive and negative ion pairs. Hence, they are known as ionizing radiations. The ionization
property of these radiations proves to be highly injurious to the protoplasm. The ionizing
radiations of ecological concern are classified as follows:
Corpuscular Radiations
These consist of streams of atomic or subatomic particles, which transfer their energy
to the matter they strike.
(i) Alpha particles
These particles are large and travel few centimeters in the air. These cause large
amount of local ionization.
(ii) Beta particles
These are small particles characterized by having high velocities. They can travel a few
meters in space. These are capable of entering into the tissues for few centimeters.
Since alpha and beta particles have low penetration power they can produce harmful
effects only when absorbed, ingested or deposited in or near living tissues.
(iii) Electromagnetic radiations
Electromagnetic radiations include waves of shorter wavelengths. These are capable of
traveling long distances and can readily penetrate the living tissue. These include gamma
rays. These can penetrate and produce effect even without being taken inside.
Other Types of Radiations
Besides radioactive radiations, some other radiations are also present in the atmosphere
(i) Neutrons
These are large uncharged particles, which do not cause radiation by themselves, but
they produce radioactivity in non-radioactive materials through which they pass.
(ii) X-rays
These are electromagnetic waves very similar to gamma rays, but originate from the
outer electron shell of radioactive substances, which are not dispersed in nature.
(iii) Cosmic rays
These are radiations from the outer space, which contain alpha and beta particles
together with gamma rays.
Sources of Radiations
The radiations are produced from the radioactive elements, which are known as
radionuclides or radioactive isotopes, e.g. Uranium. Radium, Thorium, and Carbon-14. These
contribute to background radiation. But isotopes of certain metabolically important elements
like Carbon-14, Cobalt-60, Calcium 45, Iodine-131, Phosphorus-32, etc. are not ecologically
harmful but are used as tracers. The third category of radionuclides comprises of fission
products of uranium and certain other elements. These are cesium, strontium, and plutonium
etc.
Biological Effects of Radiation
The effects of radiation have revealed that acute doses are found to be deleterious and
may kill the organisms, whereas the increase in radiation in biological environment leads
to different kinds of mutations. The effects of Cobalt-60 or Cesium-137 gamma radiations
have now been studied on communities and on ecosystems at different places. The research
concludes that Irradiations eliminate varieties in species. The sensitivity of cells, tissues and
organisms to radiation varies. The cells with larger chromosomes are more sensitive.
Herbaceous communities and early stages of succession are resistant than the mature forest.
Nuclear Fall Outs or Radioactive Fall Outs
The atomic blasts not only produce the local ionizing radiations at that time but the
radioisotopes produced as a result of explosion enter the atmosphere and continue to fallout
gradually over broad geographic areas for a very long time. These are known as nuclear
fallout or radioactive fallout. These are dangerous for life as they also produce ionizing
radiations.
Biological Effects of Fall outs
The fallout of radionuclides combines with various metals and dust and from colloidal
suspension combines with organic compounds to form complexes. The smaller particles of
radionuclides adhere tightly to the leaves of plants and produce radiation damage to leaf
tissue besides entering the tissues also. Through grazing animals these enter the food chain
directly at the primary consumers level. Radionuclides, which combine with organic
substances, enter the food chain through producer tropic level. Therefore, the radionuclides
fall out manages to enter the body of all living organisms. Radioactive Strontium-90 poses
a health hazard in human beings and other higher vertebrates. It continues to deposit in
the bones and causes bone cancer and leukemia. Radioactive Cesium-137 is known to cause
irreversible genetic changes in different organisms. The fallout radiations do cause changes
in the genetic constitution of organisms, resulting in gene mutations and chromosomal
aberrations. Their considerable, doses may kill, cripple and alter the animals and plants in
the areas.
Control of Radiation Pollution
Following measures can help in controlling the radioactive pollution:
(i) Workers in nuclear plants should be provided with nuclear gadgets and safety
measures against accidents.
(ii) Leakage of radioactive elements from nuclear reactors, laboratories, transport,
careless handling and use of radioactive fuels should be checked.
(iii) Level of radiation pollution should be monitored regularly in risk areas.
(iv) Disposal of radioactive wastes deserves special attention.
Case studies
Hiroshima and Nagasaki Episode
The tale of Hiroshima and Nagasaki is a painful experience. It is for the first time that
an atomic bomb has been exploded over human population. The incident took place on
August 6,1945 at 8:15 a.m. The bomb with an approximate temperature of around 100
million 0°C was exploded on a fine morning in Hiroshima (Japan). The temperature of the
city hiked like anything, almost like an oven. After three days, Nagasaki too suffered the
ravages of a nuclear attack. More than 1,00,000 people were reported to die just after the
event took place. Since radiations from nuclear elements remain active even after, the
generations to follow up also suffered from various diseases. Even the babies in the mother’s
womb were affected and a few perished. Blindness, deafness, skin diseases and cancers,
distortion of bones and other parts became the fortune of human civilization.
Chernobyl Accident
This incident took place in Ukraine on April 26, 1986. There was a Chernobyl nuclear
power plant in Ukraine after which the event has been named. Approximately four million
people had been reported to suffer from the accident. The accident contaminated neighboring
environment up to several kilometers. The sites were evacuated and resettlement was done
for the affected people. The radiations released affected ground water and surface waters,
affecting large areas of Europe. 131 Iodine and 137 Cesium are the most dangerous amongst
the 20-odd radioactive elements released during Chernobyl disaster. As per the Soviet Health
Ministry, 31-persons died shortly after the disaster. Of the 276,614 people who worked for
rehabilitation and cleaning operations, a total of 1065 died by the end of 1990.
Marine Pollution
All river drainages end up in the seas. On the way to sea, rivers carry large amounts
of sewage, garbage, and agricultural discharge, biocides, including heavy metals. Besides
this discharge of oils and petroleum products and dumping of radionuclides waste into sea
also cause marine pollution. Huge quantity of plastic is being added to sea and oceans. Over
50 million lb plastic packing material is being dumped in sea of commercial fleets. Many
marine birds ingest plastic that causes gastro-intestinal disorders. The chemical principle in
PCBs causes more damage as thinning of eggshell and tissue damage of egg. Radionuclide
waste in sea includes Sr-90, Cs-137, Pu-239, and And Pu-240.
The pollutants in sea may become dispersed by turbulence and ocean currents and
finally becomes a part of food chain. Bioaccumulation in food chain may result into loss of
species diversity. The pollution in Baltic sea along the coast of Finland, took place largely
from sewage and effluents from wood industries. This pollution effect brought changes. in
species diversity in the bottom fauna. In less polluted water there was rich species diversity,
which tended to decrease with increasing pollution load. In heavily polluted areas, macroscopic
benthic animals were absent, but chirognomy larvae occurred at the bottom. In marine
water the most serious pollutant is oil. Spill of oil or petroleum products due to accidents/
deliberate discharge of oil polluted waste brings about pollution. About 285 million gallons
of oil are spilled each year into ocean, mostly from transport tankers. Oil pollution causes
damage to marine fauna and flora including algae, fish, birds, and invertebrates. About
50,000 to 2,50,000 birds are killed every year by oil. The oil is soaked in feathers, displacing
the air and thus interferes with buoyancy and maintenance of body temperature.
Hydrocarbons and benzpyrene accumulate in food chain and consumption of fish by man
may cause cancer. Detergents used to clean up the spill are also harmful to marine life.
Thermal Pollution
The increase in water temperature by industrial units such as steel and iron factories,
electric powerhouses and atomic power plants may be called as thermal pollution. Some of
the industries generate their own power supply where water is used to cool the generators.
This hot water is released into the main stream, causing a warming trend of surface waters.
If the drainage is poorly flushed, a permanent increase in the temperature may result.
Many organisms are killed instantly by the hot water resulting into a high mortality.
It may bring other disturbance in the ecosystem. The eggs of fish may hatch early or fail
to hatch at all. It may change the diurnal and seasonal behaviour and metabolic responses
of organisms” It may lead to unplanned migration of aquatic animals. Macrophysics population
may also be changed. As temperature is an important limiting factor, serious changes may
be brought about even by a slight increase in temperature in a population. Heat stress
(5-1 one above the normal growing temperature of organism) induces expression of specific
gene families called heat shock genes, which lead to the synthesis of a new set of proteins
called heat shock proteins. Heat shock proteins have been found in every organism from
unicellular prokaryotes to multicultural organisms including Homo sapiens. Heat Shock
Proteins synthesis lead to acquired thermo tolerance, i.e. the ability of an organism to
withstand a normally lethal temperature. Thermo tolerant genotypes show adaptations at
various levels of organization besides showing qualitative and quantitative differences in
heat shock proteins as compared to the thermo sensitive genotypes.
Solid Waste Management
Environmental problems also include solid waste disposal. At all levels of development
human beings produce domestic wastes. These comprises of kitchen wastes, ashes from
fires, broken utensils and worn-out clothing. The industrial revolution leads to the
concentration of people in urban areas with very high population density. This resulted in
addition of new sources of wastes from shops, institutions and factories. In developed countries
services for the regular removal of domestic and trade wastes have been in operation for last
many years.
Many changes have taken place in our society. The character of the wastes has altered
with rising living standards, changes in retail distribution methods and fuel technology.
Grave environmental concerns have come up with rise in construction of new buildings,
supermarkets, and industrial wastes of many kinds. In the industrialized countries, therefore,
basic health and environmental problems have been solved in the storage and collection of
solid wastes, although major problems remain in regard to resource recovery and disposal.
The technology of wastes handling is now highly developed. The substantial sectors of
industry are engaged in the production of equipment with regard to removal of wastes.
Many institutions give technical training and support. However developing nations like
India are facing the problems of urbanization with high population densities. The developing
countries are aware of the importance of avoiding the environmental pollution. The quality
of urban environment is a matter of growing concern and the importance of solid wastes
management is increasingly being recognized
Sources and Characteristics
Solid wastes generally refer to describe non-liquid waste materials arising from domestic,
trade, commercial, industrial, agriculture and mining activities and from the public services.
Disposal of sludge’s (liquid waste) of some kind fall within the scope of solid waste
management. These arise primarily from industrial sources and from sewage treatment
plants. Solid wastes comprise countless different materials; dust, food wastes, packaging in
the form of paper, metals, plastics or glass, discarded clothing and furnishing, garden wastes
and hazardous and radioactive wastes. The method and capacity of storage, the correct type
of collection vehicle, the optimum size of crew and the frequency of collection depend mainly
on volume and density. Just as solid wastes comprise a vast number of materials, they arise
from a multitude of separate sources as well as many kilometers of streets upon which solid
wastes accumulate. Thus, the four main aspects of solid wastes management are: (i) storage
at or near the point of generation, (ii) collection, (iii) street cleansing, (iv) disposal.
The main constituents of solid wastes are similar throughout the world, but the
proportions vary widely. As personal income rises, paper increases, kitchen wastes decline,
metals and glass increase, total weight generated rises and the density of the wastes declines.
Clearly, the amount of work involved in refuse collection depends upon the weight and
volume of wastes generated and the number of collection points from which the wastes have
to be removed.
Health and environmental implications
Improper handling of solid wastes results in increased potential risks to health and to
the environment both. Direct health risks concern mainly the workers in this field, who
need to be protected, as far as possible, from skin contact with wastes. For the general
public, the main risks to health are indirect and arise from the breeding of disease vectors,
primarily flies and rats. More serious, however, and often unrecognized, is the transfer of
pollution to water, which occurs when the leach ate from a refuse dump enters surface water
or wastes, either in the open air, or in plants that lack effective treatment facilities for the
gaseous effluents. Traffic accidents can result from wastes accumulated and dispersed on to
streets and roads. They have caused death and injury to people in the surrounding areas.
There also persists the specific danger of the concentration of heavy metals in the food
chain. These metals can be taken up by the plants growing on land on which sludge has
been deposited, creating risks to the animals which graze and the humans who consume
these animals.
Economic implications
Labour and transport absorb the major part of the operating cost of solid wastes
management services. The level of mechanization that should be adopted for solid wastes
management systems relates directly to the cost of labour, as compared to that of plant and
energy. There is not much variation, worldwide, in energy or mechanical plant costs, but
there is wide variation in the range of labour costs. Thus, there are no universally applicable
solid wastes management systems. Every country must evolve indigenous technology based
on the quantity and character of the wastes, the level of national wealth, wage rates,
equipment, manufacturing capacity, energy costs etc. It is necessary to deploy a complete
set of technical skills, which derive from several professional disciplines. These include civil
and mechanical engineering, chemical engineering, transport organization, land use planning
and economics.
Refuse Collection
A refuse collection service requires vehicles and labour. For their efficient development,
three components are basic:
(1) Travel to and from the work area,
(2) The collection process, and
(3) The delivery process.
The use of large, widely spaced communal storage sites is usually a failure because the
demand placed on the householder goes beyond his willingness to cooperate. Communal
storage points should, therefore, be at frequent intervals, Madras and Bangalore provide
fixed concrete containers. They are fairly successful because they place reasonable and
acceptable duty on the residents, thus very little domestic waste is thrown in the street.
In another system of block collection, a collection vehicle travels a regular route at
prescribed intervals, usually every two days or every three days, and it stops at every street
intersection, where a bell is rung. At this signal the residents of all the streets leading from
that intersection bring their wastes containers to the vehicle and hand them to the crew to
be emptied. A crew of one or two men is adequate in number, as they do not need to leave
the vehicle.
Sanitary Landfill Disposal
Land disposal (burying of wastes) is the only approved method of disposal, which is
performed at a single site. Incineration, composting, and salvage are either a form of refuse
handling or processing. They are not complete methods of disposal, and they require disposal
of residue. Sanitary landfill can be defined as the use of solid wastes for land-reclamation,
a typical example being the restoration, by filling to the original level of man made surface
dereliction such as a disused surface, mineral excavation. Solid wastes may also be used to
improve natural features by raising the level of low-lying land to enable it to be used or
cultivation or industrial development. Thus, sanitary land filling has two essential features,
which differentiate it from crude dumping:
(i) Only sites that will be improved not degraded, by a change of level are selected.
(ii) Simple engineering techniques are used to control the manner in which the wastes
are deposited, so that dangers to public health and the environment are avoided.
Unfortunately most of the world’s wastes are disposed off by uncontrolled dumping
which blights the land for any future use and causes serious risks of water pollution and
vector breeding. Very few cities operate sanitary land filling to standards, which totally
control health and environmental dangers; most of those that do are in the industrialized
countries.
Control of Hazards
(i) Control over pathogens is dependent upon a rigorous policy of covering the wastes
soon after deposit. This serves both to isolate the wastes and to retain the heat,
which is quickly generated during aerobic decomposition.
(ii) The main source of insects will be the eggs of flies. Which have been deposited in
the wastes before they arrive at the site. Most of these will be buried deep in the
wastes and will succumb to the temperature increase.
(iii) Fire at a sanitary landfill can arise from innumerable causes, hot ashes in a vehicle
delivering wastes: a cigarette thrown by a worker; the sun’s ray though a fragment
of glass on the surface. With some kinds of wastes the consequence of fire may be
very serious and underground fires have been known that ultimately caused the
collapse of the surface into voids caused by the fire.
(iv) The pollution of static water, ditches, river or the sea occurs when a sanitary
landfill adjoins a body of water. The normal source of the leach ate causing this
pollution is rain falling on the surface.
Incineration
Open burning, barrel burning, and other related uncontrolled forms of burning have a
long history of use. Many liquid wastes and pathological wastes are best disposed of by
incineration. Originally, solid waste incineration was practiced to reduce the quantity of
refuse or disposal. After it was proven that heat could destroy most pathogens, incinerators
were used in hospitals for destruction of pathological wastes. With few exceptions, incinerators
are not “good neighbors,” and the environmental nuisances of dust. Noise and air pollution
have provoked communities to an anti-incinerator philosophy. To overcome this negative
community feeling is going to require that incineration prove its worth and that imagination
be used in the design of future units. Incineration of solid wastes yields the highest percent
of volume reduction except for Pyrolysis. Unlike a sanitary landfill, incineration of solid
wastes can be performed on the premises of apartments, supermarkets, departments’ stores,
and similar establishments.
Composting
Composting involves the biological stabilization of solid matter either under aerobic or
anaerobic conditions. The end product of composing is an organic material, which could have
beneficial value as a soil conditioner or plant mulch. In addition to producing a modified
solid waste material, which can be useful in land reclamation, composting does yield a
volume reduction of solid waste by about 40-60% of the compost able fraction pyrolysis
Pyrolysis is a thermal process where oxidation of the organic fraction is not allowed to
occur. Instead, the organic matter is evolved from the refuse with heat, leaving an ash
consisting mostly of carbon and any inorganic matter, e.g. metal and glass are not removed
before Pyrolysis. Some of the gases, which have been volatized, are condensed while the
remainder is burned to supply the heat (energy) needed to pyrolyze the material. Since
oxidation is prevented, the Pyrolysis process must be performed in an atmosphere of argon,
helium or nitrogen.
Role of an Individual in Prevention of Pollution
Which are the most viable, efficient and economical ways to eliminate pollution problems?
We very often see people blaming public and government sectors to control pollution through
controlling market mechanisms and government blaming people to avoid and check pollution.
Who would control whom? Many ecologists and environmental scientists believe in that
pollution problems can be overcome by using market mechanisms to reduce pollution rather
than rigid rules and regulations. However, on the other hand man should identify and gear
up his own potential to curb down pollution. Man could achieve this by identifying his own
role at individual level in prevention of pollution. This is possible through environmental
awareness, education and enlightenment.
Ways and means by which pollution problems can be greatly reduced at individual level
are:
1. Masses at personal level should determine to consume optimum level of resources,
which would lead a comfortable life. Because excessive resource consumption is in
someway related to pollution problems and hazards (natural and anthropogenic
both).
2. Waste disposal at personal level should be optimally reduced as waste destruction
by any means causes pollution.
3. Maintenance of vehicles should remain proper as to avoid introduction of harmful
gases and other pollutants in to the atmosphere.
4. Generators and other household gadgets that add to pollution of environment should
be kept well maintained.
5. Use of chemical fertilizers should be limited as to avoid water pollution e.g. DDT
6. Timely disposal of waste to prevent decomposition of household refuge as to check
foul odours and spread of disease by insects, flies and other pathogenic bacteria.
7. Industrialists should check for proper disposal of treated water from factory units
as to avoid thermal pollution of water bodies. They should also deploy a water
treatment plant to prevent the flow of hazardous material.
8. Service centres of vehicles should minimize the disposal of organic solvents into the
main drains.
9. Music lovers should listen and operate their music systems at optimum levels as
to avoid noise pollution

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12/05/2019 YamEen Uncategorized

5 Pollution and its Factors part 2

Sources of Water Pollution
(i) Domestic sewage
This includes household’s wastes like food wastes, synthetic detergents used for washing
clothes and cleaning bathrooms and latrines and water based paints.
(ii) Industrial effluents
The industrial wastes are discharged in the adjoining rivers and streams through flush
lines of factories. The textiles, sugar and fertilizers factories, oil refineries, drugs manufacture,
rubber, and rayon fibers, the paper industries and the chemical factories all produce Chemical
pollution.
(iii) Agricultural source
Increased use of fertilizers has become essential for high yielding crop plants. Excess
of nitrates used as fertilizers seep into ground water is carried into lakes and pond. On
entering the drinking water supply system these create several health problems.
(iv) Pesticides
These include insecticides, fungicides, nematicides, rodenticides, herbicides and soil
fumigants. These contain chlorinated hydrocarbons, organophosphates, metallic salts,
carbonates, acetic acid derivatives etc. many pesticides are non-degradable. They pass through
the food chains and accumulate in fatty tissues thus causing several health hazards.
(v) Thermal pollution
Power plants and nuclear power stations are the main sources of thermal pollution of
water where water is used for cooling and becomes hot. The hot water on entering the main
water body raises its temperature, which kills fishes and other aquatic animals and increases
the rate of respiration in aquatic plants.
(vi) Pathogenic organisms
Sewage and domestic waste from houses introduces pathogenic organisms viz., protozoa,
worms-eggs and bacteria into water. This contaminated water if consumed causes jaundice,
typhoid, dysentery, cholera, tuberculosis etc.
(vii) Mineral oils
Oil from oil spills and washings of automobiles finds way into river water through
sewers.
(viii) Underground water pollution
Underground water particularly in cities and industrial areas is no more pure and safe.
The sources of underground water pollution are sewage, seepage, pits, industrial effluents,
septic tanks, fertilizers and pesticides, garbage etc.
(ix) Marine water pollution
River and stream network sources of water ultimately end up ocean and seas. Thus,
these acts as the sink of all natural and man-made water based pollutants. The main
sources of oceanic pollution are discharges of oil, greases, petroleum products, detergents,
sewage and garbage including radioactive wastes.
Effect of Water Pollutants
The main effects of water pollutants are:
1. Compounds of mercury, arsenic and lead are poisonous and chemically harmful as
they even affect water treatment plants e.g. organic sulphur compounds interfere
with nitrification.
2. Mercury when dissolved in water is absorbed by aquatic plants and enters the food
chain. Lead impairs metabolism and brings about congenital deformities, anaemia
etc.
3. Cadmium damages kidneys and liver.
4. Inorganic nitrates and phosphates promote growth of oxygen-consuming algae,
which result in the death of fishes and other aquatic animals.
5. Presence of dyes and compounds in the discharged water changes the colour of
water.
6. Soap, detergents and, alkalis result in foam formation.
7. Industrial effluents containing iron, free chlorine, phenol, manganese, oils,
hydrocarbons, ammonia, algae and microorganisms impair the taste and odours of
water.
8. The nitrates and phosphates dissolved in water accelerate the growth of
microorganisms, which consume much of the dissolved oxygen depriving fish and
other aquatic life (Eutrophication).
9. Biomagnifications is the increase of toxic materials at each tropic level of a food
chain.
For example, DDT after reaching a water system is absorbed by the microorganisms on
which smaller fishes feed. From them, DDT reaches the carnivorous animals. Since bigger
fishes consume more food, large amounts of DDT accumulates in their body.
CONTROL OF WATER POLLUTION
(i) Separate ponds and tanks to be used for cattle and animals.
(ii) Use of pesticides, insecticides and fertilizers should be done judiciously. Rapid
biodegradable substitutes for pesticides should be employed.
(iii) In towns where sewage facilities are not available, septic tanks should be made in
the houses.
(iv) Rivers and lakes should not be used for bathing or washing as it contaminates
water. .
(v) Domestic sewage and industrial wastes should be treated before discharging them
into drains.
Treatment of waste Water
Domestic sewage and industrial wastes should be properly treated before these are
drained in the mainstream water. Treatment involves the following two steps:
(i) Sewage treatment
It involves following steps:
Primary treatment. It involves physical processing of sedimentation, flotation and
filtration where sewage water is passed through screens to remove larger particles and then
through grinding mechanism to reduce the larger particles to smaller size. The sewage is
finally passed through settling tanks to remove suspended impurities.
Secondary treatment. Sewage obtained after primary treatment is sent to aeration tank
where it is mixed with air and sludge laden with bacteria and algae. The algae provide
oxygen to the bacteria and decompose organic matter into simple compounds. Chlorination
is finally done to remove bacteria.
Tertiary treatment. In the third and last step water is passed through ion exchangers
to remove dissolved salts.
(ii) Treatment of industrial effluents
Treatment of industrial effluents involves neutralization of acids and bases, removal of
toxic compounds, coagulation of colloidal impurities, precipitation of metallic compounds
and reducing the temperature of effluents to decrease thermal pollution.
SOIL POLLUTION
Soil Pollution
Like water and air, soil is also equally important for living organisms. It supports
plants on which. all other living organisms depend. The process of soil formation is so slow
that the soil may be regarded as a non-renewable source. Therefore, the study and control
of soil pollution is important. Any substance that reduces soil productivity is called soil
pollutant.
Sources of Soil Pollution
There are several materials, which adversely affect physical, chemical and biological
properties of the soil and thus reduce its productivity. These are
1. Chemicals present in industrial waste.
2. Pesticides and insecticides that are sprayed on crops. .
3. Fertilizers and manures that are added to the soil to increase the crop yield.
Effect of Soil Pollutants
Chemicals and pesticides affect the structure and fertility of soil by killing the soil
microorganisms. Pesticides are absorbed by the plants and then transferred to other organism.
Hence, they affected food chains and food webs. Excretory products of livestock and human
beings used as manure pollute the soil besides giving high yield. The faulty sanitation and
unhygienic practices of the people add to the soil pollution. Pathogens present in the wastes
and excreta contaminate the soil and vegetable crops causing diseases in man and
domesticated animals.
Types of Soil Pollution
It is of the following types-
(i) Positive soil pollution
Reduction in the productivity of soil due to the addition of undesirable substances like
pesticides, herbicides, fertilisers, etc. is called positive pollution. These pollutants have
cumulative effect and kill the soil organisms.
(ii) Negative soil pollution
It is caused by the removal 01 useful components from soil by erosion, deforestation and
improper methods of agriculture.
Salination of Soil
Increase in the concentration of soluble salts is called salination. This adversely affects
the quality and productivity of soil. It takes place in two ways: accumulation of salts dissolved
in irrigation water on the soil surface due to intensive farming and poor drainage, and
deposition of salts as white crust during summer months drawn by capillary action from the
lower surface to the top surface.
Control of Soil Pollution
Various measure to control soil pollution are-
1. Transfer stations for bulk shifting of refuse should be constructed in cities and big
towns.
2. Pneumatic pipes should be laid for collecting and disposing wastes.
3. Materials like paper, glass and plastics can be recycled.
4. Metals should be recovered from scrap and disposed materials.
5. Use of chemical fertilizers should be reduced by the use of bio fertilizers and
manures.
6. Use of pesticides can be reduced by adopting biological control of pests.
7. Use of cattle dung and agricultural wastes in biogas plants should be encouraged.
8. Deforestation can check soil erosion to a great extent.
Land Degradation
Besides pollution, land and soil face several other problems. Removal of topsoil is called
soil erosion. Soil erosion factors are water, wind, ocean, waves and glaciers, felling of trees,
overgrazing by cattle, over-cropping etc. Erosion occurs both in wet and dry regions. It leads
to floods.
Soil Erosion in India
Soil erosion is a worldwide phenomenon, but it is especially high in Central Africa,
China, India, Nepal, Australia, Spain, USA and USSR. India loses about 40,000 hectares of
land every year as an effect of wind and water erosion. Damage to the topsoil is 18.5% of
the total world’s loss. This is due to overgrazing by livestock. The population of livestock in
India is the highest in the world. Overgrazing damages the topsoil, which reduces soil
fertility.
(i) Deforestation of overgrazing
Over-grazing is the main cause of soil erosion in India. Roots of grasses act as binding
material and keep the soil intact, which upon grazing are destroyed.
(ii) Desertification
Loss of soil productivity by erosion of top soil results in the formation of deserts.
Deserts are spreading in all continents. Desertification takes place by shifting of sand dunes
by wind and .over-grazing. That desert in India is spreading at the rate of 12,000 hectares
of land every year.
(iii) Shifting cultivation
Tribal communities follow the practice of cutting down trees and setting them on fire
and then raising the crops on the resulting ash. This is called Jhuming in northeastern
India. It is harmful if the Jhuming cycles are longer than ten years but short cycles destroy
forests and cause soil erosion. e.g. Asia and Africa. .
(iv) Developmental activities
Large areas of fertile and productive croplands, woodlands and grasslands are lost to
various developmental activities such as rapid urbanization, building of airports, industries,
railways, roads, mining and construction of dams.
Control of Land Degradation
Following ways can control Land degradation
1. Restoration of forests and grass cover can help in prevention of soil erosion and
floods.
2. By replacing shifting cultivation with crop rotation, mixed cropping or plantation
cropping. Providing adequate drainage to irrigated and flood-prone lands can prevent
salinity.
3. Desertification can be controlled by spread of appropriate plant species and by
raising trees as wind breaks.
Noise Pollution
Noise can be defined as unwanted/unpleasant sound. So noise pollution is unwanted
sound dumped into the atmosphere without regard to the adverse effects it may have. In
our country urbanization and industrialization have become twin problems. Cities and towns
have sprouted up where industries are concentrated. Lack of town’ planning had led to
residential, commercial and industrial areas being mixed up. Houses, schools and hospitals
are situated near industries. All the boons of industrialization and civilization such as
motors, horns, heavy and light machinery, work and movement, blaring radios, supersonic
aeroplanes have become disturbing and irritant. Our ears can hear ordinary conversation
between 30-60 decibels. Modern conversation has a noise value of 60 decibels. A decibel
value greater than 80 decibels causes noise pollution. Noise becomes troublesome above 140
decibels..

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12/05/2019 YamEen Uncategorized

5 Pollution and its Factors part 1

INTRODUCTION
Pollution may be defined as an undesirable change in the physical, chemical or biological
characteristics of air, water and land that may be harmful to human life and other animals,
living conditions, industrial processes and cultural assets. Pollution can be natural or manmade. The agents that pollute are called pollutants.
Pollutants
Pollutants are by-products of man’s action. The important pollutants are summarised
below:
• Deposited matter—Soot, smoke, tar or dust and domestic wastes.
• Gases—CO, nitrogen oxides, sulphur oxides, halogens (chlorine, bromine and iodine).
• Metals—Lead, zinc, iron and chromium.
• Industrial pollutants—Benzene, ether, acetic acid etc., and cyanide compounds.
• Agriculture pollutants—Pesticides, herbicides, fungicides and fertilizers.
• Photochemical pollutants—Ozone, oxides of nitrogen, aldehydes, ethylene,
photochemical smog and proxy acetyl nitrate.
• Radiation pollutants—Radioactive substances and radioactive fall-outs of the
nuclear test.
Classification of Pollutants
On the basis of natural disposal, pollutants are of two types:
(i) Non-degradable pollutants
These are the pollutants, which degrade at a very slow pace by the natural biological
processes. These are inorganic compounds such as salts (chlorides), metallic oxides waste
producing materials and materials like, aluminium cans, mercuric salts and even DDT.
These continue to accumulate in the environment.
(ii) Biodegradable pollutants
These include domestic sewage that easily decomposes under natural processes and can
be rapidly decomposed by natural/ artificial methods. These cause serious problems when
accumulated in large amounts as the pace of deposition exceeds the pace of decomposition
of disposal.
On the basis of the form in which they persist after their release into the environment,
pollutants can be categorized under two types:
(i) Primary pollutants : These include those substances, which are emitted directly
from some identifiable sources. This include-
(a) Sulphur compounds: SO2, SO3, H2S produced by the oxidation of fuel.
(b) Carbon compounds: Oxides of carbon (CO+CO2) and hydrocarbons.
(c) Nitrogen compounds: NO2 and NH3.
(d) Halogen compounds: Hydrogen fluoride (HF) and hydrochloric acid (HCl).
(e) Particles of different size and substances: These are found suspended in air.
The fine particles below the diameter of 100u are more abundant and include
particles of metals, carbon, tar, pollen, fungi, bacteria, silicates and others.
(ii) Secondary pollutants. The secondary pollutants are produced by the combination
of primary emitted pollutants. in the atmosphere. In bright sunlight, a photochemical
reaction occurs between nitrogen oxides; oxygen and waste hydrocarbons from
gasoline that forms peroxyacetyle nitrate (PAN) and ozone (O3), Both of them are
toxic components of smog and cause smarting eyes and lung damage.
(iii) Smog. The fog deposited with smoke and chemical fumes forms a dark and thick
covering, the smog. Smog is very common in almost all the industrial areas as the
smog is trapped for many days by the stagnant air. It is harmful both for animals
and plants.
AIR POLLUTION
The WHO defines air pollution as the presence of materials in the air in such
concentration which are harmful to man and his environment. A number of ingredients find
their way in the air and these are mostly gases, which rapidly spread over wide areas.
SOURCES OF AIR POLLUTION
Various sources of air pollution are fossil fuels, industries, agricultural activities, wars,
natural causes arid emissions from vehicles.
(i) Burning Fossil Fuels
Burning of wood, charcoal and other fossil fuels causes air pollution by the release of
carbon dioxide (CO2), carbon sulphur dioxide etc. Petroleum consists mainly of hydrocarbons,
sulphur and nitrogen.
(ii) Emissions from Automobiles
Vehicles are mainly responsible for more than 80% of total air pollution.

The major pollutants released from automobiles, locomotives, aircraft etc., include CO, unburnt
hydrocarbons and nitrogen oxide.
(iii) Industries
Paper and pulpfactories, petroleum refineries, fertilizer plants, and steel industries,
thermal power plants are the main sources of air pollution. They add various harmful gases
like CO, SO3, NO, Hydrocarbons etc., to the atmosphere. Textile factories release cotton dust
into the air. Cities experiencing this type of pollution are Kanpur, Surat and Ahmedabad.
The pesticide and insecticide industries are posing serious threat to the environment. Food
processing industries and tanneries emit offensive odors. Release of poisonous gases from
accidents also poses serious threats. e.g. Bhopal Gas Tragedy in which methyl isocynate
(MIC) gas leakage killed several people. In Tokyo, about 34 tones of carbon particles mixed
with other suspended particles settle per square kilometer every day.
(iv) Agricultural Activities
Spraying of insecticides and weedicides also cause air pollution. These, when inhaled
create severe problems to both animals and man.
(v) Wars
Various forms of explosives used in war pollute the air by releasing poisonous gases.
This greatly disturbs the ecology of the area. Nuclear explosions pollute air by radioactive
rays. The effects of nuclear explosions on Hiroshima and Nagasaki are well-known examples.
(vi) Natural Causes
Gas emissions from active volcanoes, marsh gas, spores of fungi and pollens are the
natural causes of air pollution.
COMMON AIR POLLUTANTS
Air pollutants are of two main types ~gaseous and particulate. Oxides of carbon. Nitrogen
and sulphur are gaseous pollutants. Particulate pollutants may be solid or liquid particles,
larger particles settle down quickly viz., sand and water droplets whereas small dust particles
remain suspended in air for a long time. These are added into the atmosphere by the
processes of blasting, drilling, crushing, grinding and mixing.
(i) Carbon Dioxide
CO
2 content of air has increased by 20% during the last century. CO2 causes nausea
and headache. It’s increase in the air may cause green house effect, rise in the atmospheric
temperature. This may melt the polar ice resulting in rise in level of oceans and flooding
of coastal regions.
(ii) Carbon Monoxide
It is a very poisonous gas and is produced by incomplete combustion of fuel. If inhaled.
it combines with hemoglobin and reduces its oxygen-carrying capacity. This leads to laziness,
reduced vision and death.

(iii) Oxides of Nitrogen
These include NO and NO
2, which are released by automobiles and chemical industries
as waste gases and also by burning of materials. These are harmful and lower the oxygen
carrying capacity of blood.
(iv) Oxides of Sulphur
SO
2 and SO3 are produced by burning of coal and petroleum and are harmful to buildings,
clothing, plants and animals. High concentration of SO2 causes chlorosis (yellowing of leaves),
plasmolysis, damage to mucous membrane and metabolic inhibition. SO2 and SO3 react with
water to form Sulphuric and sulphurous acids. These may precipitate as rain or snow
producing acid rain or acid precipitation.
(v) Photochemical Oxidants
Formed by the photochemical reactions between primary pollutants, viz. oxides of
nitrogen and hydrocarbons. Nitrogen oxides in the presence of sunlight react with unburnt
hydrocarbons to form peroxyacyl nitrate (PAN), Ozone, aldehydes and some other complex
organic compounds in the air.
(vi) Hydrocarbons
These are unburnt discharges from incomplete combustion of fuel in automobiles. These
form PAN with nitrogen oxides, which is highly toxic.
(vii) Particulate Matter
Industries and automobiles release fine solid and liquid particles into the air. Fly ash
and soot from burning of coal, metal dust containing lead, chromium, nickel, cadmium, zinc
and mercury from metallurgical processes; cotton dust from textile mills; and pesticides
sprayed on crops are examples of particulate pollutants in the air. These are injurious to
respiratory tract.
(viii) Aerosols
Aerosols are chemicals released in the air in vapour form. These include fluorocarbon
(carbon compound having fluorine) present in emissions from the Jet aeroplanes. Aerosols
deplete the ozone layer. Thinning of ozone layer results in more harmful ultraviolet rays
reaching the earth, which are harmful to skin, and can lead to skin cancer also.
(ix) Radioactive Substances
These are released by nuclear explosions and explosives. These are extremely harmful
for health.
(x) Fluorides
Rocks, soils and. minerals containing fluorides release an extremely toxic gas called
hydrogen fluoride on heating. This gas is highly injurious to livestock and cattle.
POLLUTION IN INDIA
India supports a large network of factories and industries. These factories are generally
localized in eight or ten large industrial centres. These are also a great source of air as well
water pollution. To be on a safer side delocalisation of industries is the need of the time.
This would lead to an even distribution of pollutants and faster degeneration of pollutants.
The major pollutants coming out from these industries are –
(i) Industrial Pollutants. The common air pollutants from industries are SO2, CO,
CO
2, H2S and hydrocarbons together with dust, smoke and grit. These are produced
by the burning of coal and petroleum and by the combustion of lignite at thermal
power stations. The chemical industries release HCl, chlorine, nitrogen oxide and
oxides of copper, zinc, lead and arsenic.
The fertilizer factories at Gorakhpur and Ahmedabad; the steel industries at Bhilai,
Rourkela, Jamshedpur and Durgapur pollute the air with above-said gases.
(ii) Automobile Exhausts. Automobiles run by petrol and diesel produce CO, nitrogen
oxides and hydrocarbons. Hundreds and thousands tons of hydrocarbons and CO
are emitted into air daily. Metropolitan cities harbour lakhs and crores of
automobiles. Every gallon of petrol consumed by automobiles produces 3 pounds of
carbon monoxide and 15 pounds. of nitrogen oxide.
(iii) Ionizing Radiations from Radioactive Substances. Ionizing radiations include alpha,
beta particles and the gamma rays etc. These are produced by atomic explosions
and testing of atomic weapons.
Effects of Air Pollution
Effect on Plants
(i) SO2 causes chlorosis and also results in the death of cells and tissues.
(ii) Fluorides and PAN damage leafy vegetables such as lettuce and spinach.
(iii) Oxides of nitrogen and fluorides reduce crop yield.
(iv) Smog bleaches and blaze foliage of important leafy plants.
(v) Hydrocarbons cause premature yellowing, fall of leave and flower buds, discoloration
and curling of sepals and petals.
(vi) Smoke and dust cover the leaf surface and reduce photosynthetic capacity of plants.
(vii) Ozone damages cereals, fruits, and cotton crop.
Effect on Man
The effect of pollutants on animals and man are as follows-
(i) Ozone causes dryness of mucous membranes, changes eye vision, causes headache,
pulmonary congestion and oedema.
(ii) Ozone has been reported to produce chromosomal aberrations.
(iii) SO2 causes drying of mouth, scratchy throat, smarting eyes and disorders of
respiratory tract.
(iv) SO3, CO and NO2 diffuse into blood stream and reduce oxygen transport. CO
damages cardiovascular system. Hydrocarbons and other pollutants act, as
carcinogens and lead to different cancers.
(v) Cotton dust leads to respiratory disorders e.g. bronchitis and asthma.
(vi) Smoking of tobacco causes cancerous growth in lungs.

Change in Climate
CO
2 content of air is increasing due to deforestation and combustion of fuel. This
increase is affecting the composition and balance of gases in the atmosphere. Increase in
CO
2 concentration may increase the atmospheric temperature, producing green house effect
A rise of global temperature by more than 2-3 degrees may melt glaciers and polar ice. This
would lead to a rise in ocean level and consequent flooding and submergence of coastal
areas. Rainfall pattern may also change, affecting agricultural output in various regions of’
the world. Aerosols deplete the ozone layer in the stratosphere. Thinning of ozone layer
would permit more of the harmful ultraviolet rays to reach the earth. This may cause,
sunburn, blindness and inactivation of proteins, RNA, DNA and plant pigments.
Aesthetic Loss
Dust and smoke spoils the beauty of nature. Especially the mountain environments,
which serve as a great attraction for tourists. Foul odours emitted by industries, automobiles,
dirty drains and garbage heaps in cities are a great nuisance.
Control of Air Pollution
Following measures have been suggested to control air pollution-
(i) Some gases, which are more soluble in a particular liquid than air, for example,
ammonia in water, can be separated by dissolving in it
(ii) Particles larger than 50 mm are separated in gravity settling tanks. Using cyclone
collectors or electrostatic precipitators separates fine particles.
(iii) The height of chimneys should .be increased to the highest possible level to reduce
pollution at the ground level.
(iv) SO2 pollution can be controlled by extracting sulphur from the fuel before use.
(v) Pollution control laws should be enforced strictly.
(vi) Trees should be planted on the roadside, riverbanks, parks and’ open places as they
keep the environment fresh.
(vii) Population growth, which is the main cause of pollution should be checked.
(viii) Nuclear explosions should be restricted.
Water Pollution
Water is extremely essential for life, this common fact is known to all. It is required to
meet our basic needs in day to day life viz., cooking, drinking, bathing, disposal of sewage,
irrigation, generating electricity in power plants, cooling and manufacturing different products
in industries and the disposal of industrial wastes. During all these processes the undesirable
substances are added to the water resources to a great extent. This alters the basic chemistry
of water in rivers and streams.

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12/05/2019 YamEen Uncategorized

4 Biodiversity and Conservation part 2

1. Endemic Species of India
India has a very rich element of endemics in its flora. According to Chatterjee (1940)
Indian subcontinent has about 61.5 percent to endemic flora with about 7,000 endemic speciesand 134 endemic genera. Of these the Himalayas and the Khasi Hills account for about 3,000
and Deccan peninsula for about 2,000 endemic species. These figures speak eloquently of the
great need for protecting the endemics. This can be done effectively by carefully analyzing the
floristic composition of the various phytogeographical units of Indian flora and by selecting
suitable natural forests in these units and preserving them as ‘Biosphere Reserves’.
Sapria himalayana, Uvaria Inroad, Alcimandra cathcartii Magnolia gustavii, M pealiana,
Pachylarnax pleiocarpa, Nepenthes khasiana, Dicentra royler several species of Primula and
Rhododendron and the Lady’s Slipperorchids. P. aphiopodilum insigne, P. hirsutissimum, P.
faireenum, P. spicerianum and P. venusturm, are some of the noteworthy endemics of the
Himalayas and Khasi Hills. Antiaris taxicaria, Campanual cytinoides, Pedicularis perroter
and the some species of the Podostemaceae are endemic to Western ghats/the Nilgiri Hills
in South India.
2. Endangered Flora and Fauna of India
Some plants and animals have already become extinct and there are many facing
danger of extinction. The basic reasons of extinction of wildlife are as follows:
(1) Destruction of their natural habitats due to expanding agriculture, urbanization
and industrialization.
(2) Overgrazing by domestic animals that convert the area into deserts.
(3) Poaching for meat, skin, fur, ivory, rhino horns etc.
(4) Export of some species.
The Botanical Survey of India (BSI) could so far complete survey of plant resources. in
only about 3/5th of the country. As per the targets set, BSI should have complete survey
of the remaining 2/5th of the country by 1998. It is planned to publish National Flora of the
country in 24 volumes by 2000 A.D.
The Zoological Survey of India (ZSI) could so far survey only about 1/3 of the country,
and is planned to complete the survey of the 75% of the remaining 2/3rd area of the country
by 2000 A.D. Sixty-two volumes of Fauna of India are to be brought out by 2000. Data
regarding all endangered plant and animal species of the country are also not complete. It
was set that data regarding all endangered plant species will be inventoried by 1992, for
which BSI had been restructured. In its Annual Report (1987-88); D.O. En. Has reported to
publish Vol. I of Red Data Book of Indian plants covering 235 species. Red Data Book of
Indian Plants Vol. II containing about 200 rare and endangered species is completed and
printed (D.O. En. Annual Report, I988-89). The status survey of Endangered animal species
is being done and is claimed to be completed and Red Data Book compiled by 1995.
According to the Red Data Book of IUCN (International Union for Conservation of
Nature and Natural Resources), more than 1000 creatures are threatened with extinction,
some very soon, some within a decade or so. Among these facing most immediate danger
are, all species of rhinoceros particularly the Indian variety the Royal Bengal, and Siberian
Tigers, the Mexican grizzly bear, the red wolf, the mountain gorilla; the Arabian oryx and
the Asiatic lion.Indian Endangered Flora
In India, nearly 450-plant species have been identified as endangered, threatened or
rare. A list of some such species in different parts of the country is given below (this may
not be a complete list).
Table 4.6. List of Some Endangered, Threatened or Rare Species
S.No. Species Family
Himalayas and Eastern India
1. Abies delavayi Pinaceae
2 Acanthephippium sylhetense Orchidaceae
3. Aconitum deinorrhzum Ranunculaceae
4. Adinandra griffithii Theaceae
5. Aglaia perviridis Meliaceae
6. Amblyanthus multiflorus Myrsinanceae
7. Anacolosa ilicoides Oleaceae
8. Anoectolchilus sikkimensis Orchidaceae
9. Angopteris eracta Angiopteridaceae
10. Aphyllorchis Montana Orchidaceae
11. Arachnanthe cathcartii Orchidaceae
12. A. clarkei Orchidaceae
13. Artemisia Asteraceae
14. Astragalus strobiliferus Papilionaceae
15. Camellia caduca Theaceae
16. Cyathea gigontean Cyatheaceae
17. C. elegans Orchidaceae
18. Dendrobium densiflorum Orchidaceae
19. Dioscorea deltoidea Dioscoreaceae
20. D. ruflesiana Asclepiadacea
21. Gentiana Kurroo Gentianaceae
22. Lespedeza elegans Papilionaceae
23. Nardostachys grandiflora Valerianaceae
24. Nepenthes khasiana Nepenthaceae
25. Osmynda regalis Osmundaceae
26. Picea brachytyla Pinaceae
27. Rauvolfia serpentina Apocynaceae
28. Rhododendron arizelum Ericaceae
29. Saussurea bracteata Asteraceae
30. S. lappa Asteraceae
31. Zanthoxylum scandens Rutaceae

Rajasthan and Gujarat
32. Commiphora wightii Burseraceae
33. Helichrysum cutchicum Asteraceae
34. Hyphaene dichotoma Arecaceae
35. Meconopsis betonicifolia Papaveraceae
Gangetic plain
36. Aldrovanda vesiculosa Droseraceae
Peninsular India
37. Anemia tomentosa Schizaeaceae
38. Ceropegia fantastica Asclepiadaceae
39. Cycas beddomei Cycadaceae
40. Lobelia nicotionaefolia Lobeliaceae
41. Piper barberi Piperaceae
42. Pterospermum obtusifolium Sterculiaceae
Andaman and Nicobar Islands
43. Depterocarpus kerrii Dipterocarpaceae
44. Hippocratea nicobarica Hippocrateaceae
45. Lagerstroemia hypoleuca Lythraceae
46. Myristica andamanica Myristicaceae
47. Podocarpus neriifolius Podocarpaceae
48. Uvaria nicobarica Annonaceae
Indian Endangered Fauna
Some of the animal species listed below has been identified as endangered ones. This
may not be a complete list. The chici’s species are:
Table 4.7 : List of Animals Species
Mammals Four-horned antelope Bengal florican
Lion-tailed macaque Indian bison Nicobar pigeon
Nilgirilangur Wild yask Wreathed hornbill
Indian wolf Gangetic dophin Reptiles
Red fox Baleen whales Turtle
Himalayan Brown bear Marinedolphines Tortoise
Red panda Birds Terrapin
Indian Lion Geese Green sea turtle
Leopard Black eagle Tortoise shell turtle
One-horned rhinoceros Bamboo partridge Esturine crocodile

Indian wild ass Mountain quail Marsh crocodile
Andaman wild pig Chir pheasant Monitor lizards
Kashmir stag Peacock pheasant Indian python
Swamp deer Indian peafowl Amphibia
Alpine musk deer Blacknecked crane Viviparous toad
Blackbuck Masked finfoot Indian salamander
Chinkara Houbra bustard
CONSERVATION OF BIODIVERSITY
The hope for conservation of natural biodiversity however rests on preservation of
selected ecosystems and representative areas of different vegetation types in the country. as
well as on saving some of the extinction-prone species. The number of endangered species
of plants and animals is on the rise, which has prompted government and non-governmental
organizations to take certain steps in this direction. Forestry and wildlife were primarily
under the control of state governments but later on looking to the gravity of the situation
a separate Ministry of Environment and Forests was established.
The aims and objectives of wildlife management in India includes the following
(i) Protection of natural habitats
(ii) Maintenance of a viable number of species
(iii) Establishment of biosphere reserves
(iv) Protection through legislation
Some of the non-government organizations working in this direction are
(i) Bombay Natural History Society
(ii) Wildlife Preservation Society of India, Dehradun.
(iii) World Wide Fund for Nature India (WWF)
Laws Governing Biodiversity Conservation in India
(i) The Madras Wild Elephant Preservation Act, 1873.
(ii) All India Elephant Preservation Act, 1879.
(iii) The Indian Fisheries Act, 1897.
(iv) Wild Birds and Wild Animals Protection Act, 1912.
(v) The Indian Forest Act, 1927.
(vi) Bengal Rhinoceros Act, 1932.
(vii) Haily National Park Act.. 1936.
(viii) Bombay Wild, Animals and Wild Birds Protection Act, 1951.
(ix) Assam Rhinoceros Protection Act, 1954.
(x) The Cruelty Against Animals Act, 1960.
(xi) The Wildlife (Protection) Act, 1972.

(xii) The Forest (Conservation) Act, 1980.
(xiii) Wildlife (Protection) Amendment Act; 1991.
Conservation of Forests and National Ecosystems Act, 1994.
IN-SITU AND EX-SITU CONSERVATION OF BIODIVERSITY
The goal of biodiversity conservation can be attained in a number of ways. The concept
of gene banks regulates all these methods.
In-situ conservation
It can be defined as the conservation of plants and animals in their native ecosystem
(natural habitats) or even man made ecosystem, where they naturally occur.
This type of conservation is applicable to wild flora and fauna as conservation is achieved
through protection of populations in their natural ecosystems. The concept of protected
areas falls under this category e.g. National Parks, Sanctuaries and Biosphere reserves
etc.
Ex-situ conservation
It can he defined as the conservation of plants and animals away from their natural
habitats, which includes collection of samples of genetic diversity and their treatment in the
laboratory, where they are cultured.
The concept of ‘gene banks’ has primarily become the talk for ex-situ conservation as
it is important for conservation of agricultural crops and forestry based afforestation
programmes. Genetic resource centres fall under this category and include botanical gardens,
zoos etc.
INSTITUTIONS FOR “EX-SITU” CONSERVATION OF BIODIVERSITY
(a) National Bureau of Plant Genetic Resources (NBPGR)
The set up was established in 1976 by the Indian Council of Agricultural Research
(ICAR) New Delhi for “Ex-Situ” conservation of plant genetic resources for agri-horticultural
and agri-silvicultural activities. Built- in long term cold storage (Gene Banks) have been
installed in New Delhi to conserve genetic resources at low temperature of 20°C. At present,
NBPGR holds about 48.5 thousand accessions of diverse species of economically important
plants (Khanna & Singh 1987). A number of scientific organizations dealing with storage of
genetic material of various crop plants have been established in India after independence.
They are “Rice Research Institute”, Cuttack, “Potato Research Institute”, Shimla & “Indian
Institute of Horticultural Research”, Bangalore.
(b) National Bureau of Animal Genetic Resources (NBAGR)
It was established in the 1980’s in Kamal, Punjab: for preservation of germless of
improved varieties of cattle’s-cows, buffaloes, goats, sheep, camels and oxen and their various
breeds found in different parts of India. Other organizations for “ex-situ” conservation of
animal germplasm are “National Bureau of Fish Genetic Resources”. Lucknow and Wildlife

Research Institute of India, Dehradun. At WRI a “gene bank” of all wild and domesticated
animals of India is coming up.
Protected areas of India for “In-Situ” Conservation of Biodiversity:
Three types of protected areas-
(i) Wildlife Sanctuaries;
(ii) National Park;
(iii) Biosphere Reserves were created in India for “In-Situ” conservation of biodiversity.
As on 31 March, 1994 there were 421 Wildlife Sanctuaries, 75 National Park, 14
Biosphere Reserved in India covering about 4% of total geographical area. In-situ conservation
of wildlife is a comprehensive system of protected areas. There are different categories of
protected areas, which are managed with different objectives for bringing benefits to the
society. The major protected areas include: (i) National Parks, (ii) Sanctuaries, (iii) Biosphere
Reserves etc. These areas vary considerably in size, design, purpose and effectiveness of
management.
Table 4.8. Distribution between National Park, Sanctuary and Biosphere Reserve
S.No. National Park Sanctuary Biosphere Reserve
1. Associated to the habitat These are species oriented Takes into consideration
of wild animal species as pitcher plant, Great the entire ecosystem.
like rhino, tiger, lion etc. Indian Bustard.
2. The size range is Size range is Size range over
0.04-3162 sq.km. 0.61-7818 sq. km. 5670 sq. km.
3. Boundaries marked by Boundaries not sacrosanct Boundaries marked by
legislation legislation
4. Disturbance only limited Limited disturbance Disturbance only limited
to buffer zone to buffer zone.
5. Tourism allowed Tourism allowed Tourism generally not allowed
6. Scientific management Scientific management Scientifically managed
is lacking is lacking
7. No attention is paid to No attention is paid to Attention is paid
gene pool conservation gene pool conservation
(i) National Park
According to the Indian Board for Wild Life (IBWL), “a National Park is an area
dedicated by statute for all time to conserve the scenery, natural and historical objects, to
conserve the wild life there in and to provide for enjoyment of the same in such manner and
by such means, that will leave them unimpaired for the enjoyment of future generations
with such modification as local conditions may demand”.
The history of National parks in India begins in 1936 when the Hailey (now Corbett)
national parks of United Provinces (now Uttar Pradesh) was created. The area is declared
for the protection and preservation for all time of wild animal life and wild vegetation for
the benefit and advantage and enjoyment of the general public. In this area hunting of
fauna or collection of flora is prohibited except under the direction of park authority.

Table 4.9. Wildlife Reserves in Different Status
State Wildlife Reserve
Andhra Pradesh Kawal, Pocharam, Neelapattu
Arunachal Pradesh Namidapha
Assam Kaziranga, Manas
Bihar Hazaribarh, Belta
Goa Mollen
Gujarat Gir, Wild Ass, Nal Sarovar
Haryana Sultanapur lake
Himachal Pradesh Gobin-sagar
Jammu & Kashmir Dachingam
Karanataka Bandipur, Nagarhole
Kerala Periyar, Neyyar
Madhya Pradesh Kanha
Maharashtra Pench, Nawegaon, Dhakna-Kolkaz
Manipur Keibul
Meghalaya Balapakrani
Mizoram Dampa
Nagaland Intangki
Orissa Simplipal, Chilka lake
Punjab Abohar
Rajasthan Ranthambore, Ghana
Sikkim Kanchenjunga
Tamil Nadu Guindy, Mundumalai, Annamalai
Uttar Pradesh Corbett, Dudwa
West Bengal Mahanandi, Jaldapara, Deer Parks, Sunderban
(ii) Sanctuary
The Indian Board for Wild Life has defined a sanctuary as, ‘An area where killing,
hunting, shooting or capturing of any species of bird or animal is prohibited except by or
under the control of highest authority in the department responsible for the management
of the sanctuary and whose boundaries and character should be sacrosanct as far as possible.
By June 1992 India had 416 sanctuaries. The Board has further clarified the position by
stating that while the management of sanctuaries does not involve suspension or restriction
of normal forest operation, it is desirable to aside a completely sacrosanct area within a
sanctuary to be known as ‘Abhyaranya’. It has also indicated that sanctuaries should be
made accessible to the public.

In India sanctuary is usually created by an order or gazette notification of State
government. So the weakness of a sanctuary is that it can be desanctuarized merely by
another order or gazette notification of a State government because it is not safeguarded by
any proper legislation. The idea behind a wild life sanctuary and a national park is same,
i.e., maximum protection, preservation and conservation of wild animals. But the fundamental
difference between the two is that a sanctuary is created by order of a competent authority,
who may be the chief conservator of forest: or minister of a State, while a national park can
be harmed, abolished or changed only by the legislation of a State. There are, title status
and degree of permanency and protection is much higher in a national park than in a
sanctuary. In a wild life sanctuary private ownership rights may continue and forestry
usages also may continue so long as wild life conservation is not adversely affected. However,
in a national park all private ownership rights are extinguished and all forestry and other
usages are prohibited. Every national park should have the minimum requisites of fauna,
flora and scenery etc. There should be sufficient means of management and protection in a
sanctuary to be upgraded as national park.
(iii) Biosphere Reserves
Biosphere Reserves have been described as undisturbed natural areas for scientific
study as well as areas in which conditions of disturbance are under control. These serve as
the centres for ecological research and habitat protection, The “Biosphere consists of two