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CHAPTER- 1
MULTIDISCIPLINARY NATURE OF ENVIRONMENTAL STUDIES
AND NATURAL RESOURCES
UNIT I MULTIDISCIPLINARY NATURE OF ENVIRONMENTAL STUDIES
Definition – Scope and importance – Need for public awareness
NATURAL RESOURCES
Renewable and Non-renewable resources- Natural resources and Associated problems-
Forest resources:-Use and over – Exploitation – Deforestation – Case studies – Timber
extraction – Mining – Dams and their ground water – Floods – Drought – Conflicts over
water – Dams – Benefits and Problems – Mineral Resources:- Use Effects on Forests and
Tribal People – Water Resources:- Use and Over-Utilization of Surface and Exploitation,
Environmental Effects of Extracting and Using Mineral Resources, Case Studies – Food
Resources: World Food Problems, Changes caused by Agriculture and Overgrazing, Effects
of Modern Agriculture, Fertilizer- Pesticide Problems, Water Logging, salinity, Case Studies
- Energy Resources:- Growing Energy Needs, Renewable and Non Renewable Energy
Sources, Use of Alternate Energy Sources, Case Studies
1.1 MULTIDISCIPLINARY NATURE OF ENVIRONMENTAL STUDIES
1.1.1 INTRODUCTION
The word environment is derived from the French word ‘environner’ which means
to ‘encircle or surround’.
Thus our environment can be defined as “the Social, Cultural and Physical
conditions that surround, affect and influence the survival, growth and
development of people, animals and plants”
This broad definition includes the natural world and the technological environment
as well as the cultural and social contexts that shape human lives.
It includes all factors (living and nonliving) that affect an individual organism or
population at any point in the life cycle; set of circumstances surrounding a
particular occurrence and all the things that surrounds us.
1.1.2 SEGMENTS OF ENVIRONMENT
Environment consists of four segments.
- Atmosphere- Blanket of gases surrounding the earth.
- Hydrosphere- Various water bodies present on the earth.
- Lithosphere- Contains various types of soils and rocks on the earth.
- Biosphere- Composed of all living organisms and their interactions with the
environment.
1.1.3 MULTIDISCIPLINARY NATURE OF ENVIRONMENTAL STUDIES
The Environment studies is a multi-disciplinary science because it comprises various
branches of studies like chemistry, physics, medical science, life science,
agriculture, public health, sanitary engineering etc.
It is the science of physical phenomena in the environment. It studies about the
sources, reactions, transport, effect and fate of physical and biological species in
the air, water, soil and the effect of from human activity upon these.
As the environment is complex and actually made up of many different
environments like natural, constructed and cultural environments, environmental
studies is inter disciplinary in nature including the study of biology, geology,
politics, policy studies, law, religion engineering, chemistry and economics to
understand the humanity’s effects on the natural world.
This subject educates the students to appreciate the complexity of environmental
issues and citizens and experts in many fields.
By studying environmental science, students may develop a breadth of the
interdisciplinary and methodological knowledge in the environmental fields that
enables them to facilitate the definition and solution of environmental problems.
1.1.4 SCOPE OF ENVIRONMENTAL STUDIES
Environmental studies as a subject has a wide scope. It includes a large number of
areas and aspects, which may be summarized as follows:
Natural resources - their conservation and management
Ecology and Biodiversity
Environmental pollution and control
Human population and environment
Social issues in relation to development and environment
At present a great number of environmental issues, have grown in size and
complexity day by day, threatening the survival of mankind on earth. These issues
are studied besides giving effective suggestions in the environment studies.
The environment studies enlighten us, about the importance of protection and
conservation of our natural resources, indiscriminate release of pollution into the
environment etc.
Environment studies have become significant for the following reasons:
1. Environment Issues being of International Importance:
It has been well recognized that environment issues like global warming, ozone
depletion, acid rain, marine pollution and loss of biodiversity are not merely national
issues but are global issues and hence must be tackled with international efforts and
cooperation.
2. Problems Cropped in The Wake of Development:
Development, in its wake gave birth to Urbanization, Industrial Growth,
Transportation Systems, Agriculture and Housing etc. However, it has become
phased out in the developed world. The North, to cleanse their own environment has,
fact fully, managed to move ‘dirty’ factories to South. When the West developed, it
did so perhaps in ignorance of the environmental impact of its activities. Evidently
such a path is neither practicable nor desirable, even if developing world follows that.
3. Explosively Increase in Pollution:
World census reflects that one in every seven persons in this plant lives in India.
Evidently with 16 per cent of the world's population and only 2.4 per cent of its land
area, there is a heavy pressure on the natural resources including land. Agricultural
experts have recognized soils health problems like deficiency of micronutrients and
organic matter, soil salinity and damage of soil structure.
4. Need for An Alternative Solution:
It is essential, specially for developing countries to find alternative paths to an
alternative goal. We need a goal as under:
(1) A goal, which ultimately is the true goal of development an environmentally
sound and sustainable development.
(2) A goal common to all citizens of our earth.
(3) A goal distant from the developing world in the manner it is from the over-
consuming wasteful societies of the “developed” world.
5. Need To Save Humanity From Extinction:
It is incumbent upon us to save the humanity from extinction. Consequences to our
activities cause destructing the environment and depleting the biosphere, in the
name of development.
6. Need For Wise Planning of Development:
Our survival and sustenance depend. Resources withdraw, processing and use of the
product have all to be synchronized with the ecological cycles in any plan of
development. Our actions should be planned ecologically for the sustenance of the
environment and development.
1.1.6 NEED FOR PUBLIC AWARENESS
1. Growing Population: A population of over thousands of millions is growing at
2.11 per cent every year. Over 17 million people are added each year. It puts
considerable pressure on its natural resources and reduces the gains of
development. Hence, the greatest challenge before us is to limit the population
growth. Although population control does automatically lead to development, yet
the development leads to a decrease in population growth rates.
2. Poverty: India has often been described a rich land with poor people. The poverty
and environmental degradation are mixed with one another. The vast majority of
our people are directly dependent on the nature resources of the country for their
basic needs of food, fuel shelter and fodder. About 40% of our people are still
below the poverty line.
3. Environment degradation has adversely affected the poor w ho depend upon the
resources of their immediate surroundings. Thus, the challenge of poverty and the
challenge of environment degradation are two facets of the same challenge.
4. Agricultural Growth: The people must be made familiar with the methods to
sustain and increase agricultural growth without damaging the environment. High
yielding varieties have caused soil salinity and damage to physical structure of soil.
5. Need to Increase Ground water: It is essential of rationalizing the use of
groundwater. Factors like community wastes, industrial effluents, chemical
India’s 3,245 towns and cities, only 21 have partial or full sewerage and treatment
facilities. Hence, coping with rapid urbanization is a major challenge.
9. Air and water Pollution: Majority of our industrial plants are using outdated and
pollution causing technologies and makeshift facilities devoid of any provision of
treating their wastes. A great number of cities and industrial areas have been
identified as the worst in terms of air and water pollution. Acts are enforced in the
country, but their implement is not so easy. The reason is their implementation
needs great resources, technical expertise, political and social will. Again the people
are to be made aware of these rules. Their support is indispensable to implement
these rules.
1.1.7 INSTITUTIONS IN ENVIRONMENT
Managing natural resources require efficient institutions at all levels i.e. local,
national, regional and global. Among the large number of institutions that deal with
environmental protection and conservation, a few well-known organization include
government organizations like the BSI and ZSI, and NGOs like the BNHS, WWF-1, etc.
The Bombay Natural History Society (BNHS) , Mumbai
World Wide fund for nature- India (WWF-1), New Delhi
Centre or science and environment (CSE), New Delhi
C.P.R Environmental Education Centre, Madras
Centre for Environment Education (CEE)
Bharati Vidyapeeth University, Institute of Environment Education &
Research, Pune
The Salim Ali Center for Ornithology and Natural History (SACON)
Wild life Institute of India (WII), Dehradhun
Zoological survey of India (ZSI)
The madras Crocodile Bank Trust (MCBT)
Botanical Survey of India (BSI)
1.2 NATURAL RESOURCES
1.2.1 INTRODUCTION
Natural resources can be defined as ‘variety of goods and services provided by
nature which are necessary for our day-to-day lives’.
Eg: Plants, animals and microbes (living or biotic part), Air, water, soil, minerals,
climate and solar energy (non- living or abiotic part).
They are essential for the fulfillment of physiological, social, economical and cultural
needs at the individual and community levels.
1.2.2 TYPES OF NATURAL RESOURCES
They are of two types of resources namely Renewable and Non-Renewable
Resources.
1. Renewable resources: The resources that can be replenished through rapid
natural cycles are known as renewable resource. These resources are able to
increase their abundance through reproduction and utilization of simple
substances.
Ex: Plants, (crops and forests) and animals.
Some examples of renewable resources though they do not have life cycle but
can be recycled.
Ex: Wood and wood-products, pulp products, natural rubber, fibers
(e.g. Cotton, jute, animal wool, silk and synthetic fibers) and leather.
In addition to these resources, water and soil are also classified as renewable
resources.
Solar energy although having a finite life, as a special case, is considered as a
renewable resource in as much as solar stocks is inexhaustible on the human
scale.
2. Non renewable resources: The resources that cannot be replenished through
natural processes are known as non-renewable resources. These are available in
limited amounts, which cannot be increased. These resources include fossil fuels
(petrol, coal etc.), metals (iron, copper, gold, silver, lead, zinc etc.), minerals
and salts (carbonates, phosphates, nitrates etc.).Once a non-renewable
resource is consumed, it is gone forever.
about 12% thus we need not only to protect our existing forests but also to increase our
forest cover.
1.2.4.1 FUNCTIONS OF FOREST
- It performs very important function both to human and to nature.
- They are habitats to millions of plants, animals and wild life.
- They recycle rain water.
- They remove pollutant from air.
- They control water quality.
- They moderate temperature and weather.
- They influence soil condition and prevent soil erosion.
1.2.4.2 USES OF FOREST
- Commercial uses
- Ecological uses
1. Commercial uses:
i. Wood – used as a fuel
ii. Supply wood for various industries – Raw materials as pulp, paper, furniture
timber etc.
iii. Minor forest products – gum, dyes, resins
iv. Many plants – Medicines
v. Supply variety of animal products – honey. Ivory, horns etc.
vi. Many forest lands are used for - Mining, grazing, for dams and recreation.
2. Ecological uses: Forest provides number of environmental services.
i. Production of oxygen: Photosynthesis produces large amount of oxygen
which is essential for life.
ii. Reducing global warming: Carbon dioxide is one of the main green house
gas. It is absorbed by plants for photosynthesis. Therefore the problem of
global warming caused by CO 2
is reduced.
iii. Soil conservation: Roots of trees bind the soil tightly and prevent soil
erosion. They also act as wind breaks.
iv. Regulation of hydrological cycle: Watershed in forest act like giant
sponges and slowly release the water for recharge of spring.
v. Pollution moderators: Forest can absorb many toxic gases and noises and
help in preventing air and noise pollution.
vi. Wild life habitat: Forest is the home of millions of wild animals and plants.
12.4.3 REASON FOR DEFICIENCY OF FOREST:
In India the minimum area of forest required to maintain good ecological balance is about
33% of total area. But at present it is only about 12%. So over exploitation of forest
material occurs.
1.2.4.4 OVER EXPLOITATION OF FOREST: Due to over population, there is an
increased demand for medicine, shelter, wood and fuel. Hence exploitation of forest
materials is going on increasing.
Cause of over exploitation:
- Increasing agricultural production.
- Increasing agricultural activities.
- Increase in demand of wood resources.
1.2.4.5 DEFORESTATION: It is process of removal of forest resources due to natural
or manmade activities (i.e.) destruction of forests.
Causes of deforestation:
- Developmental projects: Developmental projects causes deforestation through
two ways.
Through submergence of forest area.
Destruction of forest area.
Ex: big dams, hydro electric projects, road construction etc.
- Mining operations: It reduces forest areas. Ex: Mica, coal, Manganese and
lime stone.
- Raw materials for industries: Wood is an important raw material for various
purposes.
Ex: Making boxes, furniture and paper etc.
- Fuel requirement: Wood is the important fuel for rural and tribal population.
Deforestation in the Himalayan region, involves clearing of natural forests and
plantation of monoculture like Eucalyptus. Nutrient in the soil is poor; therefore soil losing
their fertility, hence, Himalayan area facing the serious problem of desertification.
1.2.4.7 MAJOR ACTIVITIES IN FORESTS
1.2.4.7.1 TIMBER EXTRACTION
Wood used for engineering purposes like building houses, making furniture is called
timber. The products derived from timber have been important to many civilizations, and
thus it has acquired value within these civilizations. Timber extraction results in
deforestation and in the fragmentation of the last remaining forests. It harms valuable
species of trees, birds and wild animals. In spite of this, it is sometimes necessary to
extract timber, so as to meet the needs of a developing country. During the extraction of
timber, cutting, felling and handling should be done selectively, carefully and in a planned
manner, in order to save the remaining forests and biodiversity.
Effects of Timber Extraction
The major effects of timber extraction on forest and tribal people include:
- Poor logging results in a degraded forest.
- Floods may be intensified by cutting of trees or upstream watersheds.
- Loss of biodiversity.
- Climatic changes such as less rains.
- New logging roads permit shifting cultivators to gain access to logged areas
and cut the remaining trees.
- It results in forest fragmentation which promotes loss of biodiversity because
some species of plants and animals require large continuous areas of similar
habitat to survive.
- Exploitation of tribal people by the contractors.
- Soil erosion especially on slopes occurs extensively.
- Sedimentation of irrigation systems, floods may be intensified by cutting of
trees on upstream.
Case Study-Chipko Movement
The world famous Chipko Movement , pioneered by Dasohli Gram Swarajya
Mandal in Gopeshwar brought about a general awareness about conservation of forests.
The first Chipko Movement dates back to 1731, when a village woman named Amrita Bai
led the Bishnoi women against the Maharajas men to prevent them from cutting trees. In
this attempt to save the trees, she sacrificed her life along with the lives of her husband,
three daughters and 363 people. The movement was given this name because the village
women embraced or hugged the trees to stop them from being cut. In 1972, in Uttar
Pradesh, the Chipko Movement was led by Bachnoi Devi of Advani who protected the hill
forests from the contractors axe men.
1.2.4.7.2 DAMS
Today there are more than 45,000 large dams around the world, which play an important
role in communities and economies that harness these water resources for their economic
development. Current estimates suggest some 30-40% of irrigated land worldwide relies
on dams. Hydropower, another important the use of stored water, currently supplies 19%
of the world’s total electric power supply and is used in over 150 countries. The world’s
two most populous countries – China and India – have built around 57% of the world’s
large dams.
Dams problems
Dams are the massive artificial structures built across the rivers to store water for much
beneficial purpose.
Dams are considered a “Temples of modern India”. Dams destruct vast area of
forest area. India has more than 1600 large dams.
Effects of dams on forest:
- Thousands of hectares of forest will be cleared.
- Killing of wild animals and destruction of aquatic life.
- Spreading of water borne diseases.
- Water logging increases the salinity of the soil.
Ex: Narmadha Sagar project it has submerged 3.5 lakhs hectares of forest.
Effects of dam on tribal people
- Construction of big dams lead to the displacement of tribal people.
- Displacement and cultural change affects the tribal people both mentally and physically.
- They do not accommodate the modern food habits and life style.
- Tribal people are ill treated by the modern society.
Effects of mining
- Pollute soil, water and air.
- Destruction of natural habitat.
- Continuous removal of minerals leads to the formation of trench where water is
logged which contaminates the ground water.
- Vibrations cause earth quakes.
- Produces noise pollution
- Reduces shape and size of the forest.
- Increased risk of landslides.
- Spoils the aesthetic beauty.
1.2.5 WATER RESOURCES
Water claims to be an important resource. An important use of water in our country
is for irrigation. Besides, water is also required in large amounts for industrial and
domestic consumption.
1.2.5.1 USES
Is essential for all forms of life.
Many uses of water include agricultural, industrial, household, recreational and
environmental activities. Virtually, all of these human uses, require fresh water.
No plant or animal species can survive without water. If water in our body drops by
1% we feel thirst, if it drops by 10% we face death.
1.2.5.2 HYDROLOGICAL CYCLE:
Water from various water bodies
Evaporated by solar energy
Enters in to the atmosphere as clouds
Falls again on earth as rain or snow
Ultimately returns to the ocean.
1.2.5.3 DISTRIBUTION OF WATER RESOURCES
Fresh water resources
Surface water Underground water
Standing water bodies flowing water bodies
1.2.5.3.1 UNDERGROUND WATER
Aquifer: Layers of highly permeable rock that can store water is called an aquifer. Layer
of sand and gravels are good aquifers. Clay and crystalline rocks are not good aquifers.
Effects of over utilization of water
1. Decrease of ground water:
i. Increased usage decreases the ground water.
ii. Insufficient rain fall
iii. Building construction activities sealing the permeability of the soil.
2. Ground subsidence: If ground water withdrawal is greater than it’s recharge rate,
then the sediments in the aquifers get compacted. As a result shrinkage of land surface
takes place.
Problems: a. Structural damages to the buildings
b. Fracture in pipes.
c. Reversing the flow of canals.
3. Lowering of water table: Over utilization of ground water in arid and semi arid
regions for agriculture disturbs the state of equilibrium of the hydrological cycle.
Problem: a. Lowering of water table
b. Decrease the number of aquifers
c. Change the speed and direction of water.
4. Intrusion of salt water: In coastal area over exploitation of ground water leads to
the intrusion of salt water from sea. Therefore that water cannot be used for drinking and
agriculture.
6. Rain fall: The erratic and inadequate rainfall results in reduction in storage in
subsurface reservoirs. The building construction activities are sealing the permeable
zone, reducing the area for percolation of rainwater into subsurface and increase in
surface runoff.
7. India’s increasing demand for water for intensive irrigated agriculture, for generating
electricity, and for consumption in urban and industrial centers, has been met by
creating large dams. Dams support 30 to 40% of this area.
1.2.5.4 FLOOD
It is an over flow of water. It happens when the magnitude of flow of water exceeds the
carrying capacity of the channel within its bank.
1.2.5.4.1 CAUSES OF FLOOD
- Heavy rainfall, melting of snow and sudden release of water from dams. (Flash floods)
- Reduction in the carrying capacity of the channel.
- Deforestation, mining and over grazing increase the runoff from rains and the level of
flood raises.
1.2.5.4.2 EFFECT OF FLOOD
- Water spreads in the surrounding area and submerges them.
- Cultivated land gets affected.
- Extinction of civilization.
1.2.5.4.3 FLOOD MANAGEMENT
- Floods can be controlled by dams.
- Channel management control flood.
- Flood hazards reduced by forecasting or flood warning.
- Flood may also be reduced by reduction of run off by increasing infiltration through
appropriate afforestation in the catchment area.
1.2.5.5 DROUGHT
Drought is nothing but scarcity of water, which occurs due to
- Inadequate rain fall
- Late arrival of rain fall
- Excessive withdrawal of ground water.
Lack of water for the needs of agriculture, livestock, industry or human population may be
termed as a drought. Drought causes serious damages to plants, animals and human life.
1.2.5.5.1 CAUSES OF DROUGHT
- When annual rain fall is below normal and less than evaporation, drought is created.
- High population.
- Intensive cropping pattern
Ex: Maharashtra - There has been no recovery from drought for the last 30
years due to over exploitation of water by sugarcane crop.
1.2.5.5.2 EFFECTS OF DROUGHT
- Drought causes hunger, malnutrition and scarcity of drinking water an also changes
the quality of water.
- Drought causes widespread crop failure leading to acute shortage of food and
adversely affects human and live stock population.
- Worst situation of drought causes desertification.
- Raw materials of agro based industries are critically affected during drought time,
hence industrial and commercial growth decreases.
- Drought increases the degradation of natural resources.
- Drought causes large migration of people and urbanization.
1.2.5.5.3 DROUGHT MANAGEMENT
- Indigenous knowledge is essential.
- Rain water harvesting system.
- Construction of reservoirs to improve ground water level.
- Modern irrigation technology (drip irrigation) very useful to conserve water.
- Afforestration activities also improve the potential of water in the drought area.
- Crop mixing and dry forming are the suitable methods which minimize the risk of crop
failures in dry area.
1.2.5.6 DAMS
Dams made significant contributions to human development and the benefits
derived from them have been considerable. Large dams are designed to control floods and
to help the drought prone areas, with supply of water. But large dams have proved to
