Unit- 3
Earth’s biosphere is gifted with enormously various kinds of environments which give
innumerable goods and services to human kind.
Definition: Any component of the natural environment that can be utilized by
man to support his welfare is considered as a natural resource.
The natural resource can be a substance, an energy unit or a natural process or
phenomenon.
Land, soil, water, forests, grasslands, etc. are examples of important natural resources.
Some of the resources (e.g. soil, water) are important components of the life-supporting
system.
Besides being source of food, fodder and shelter, natural resources also provide
recreational opportunities, relief and even inspiration to mankind.
Natural resources have been exploited by humans since the beginning of civilization or
even before.
During the last millennia human population has increased significantly causing serious
damage or destruction of natural resources.
Types of Natural resources
i) Inexhaustible resources: The resources which cannot be
exhausted by human consumption are called inexhaustible
resources.
These include energy sources like solar radiation, wind
power, water power (flowing streams), tidal power, and substances
like sand, clay, air, water in oceans, etc.
ii) Exhaustible resources: the resources, which are available in
limited quantities and are going to be exhausted as a result of
continuous use.
These are called exhaustible resources. For example, the stock of
coal in the earth is limited and one day there will be no more coal
available for our use.
The exhaustible resources having two categories as,
Renewable resources: Some of the exhaustible resources are naturally
regenerated after consumption and are known as renewable resources. E.g.
Forest trees and plants that make a forest may be destroyed but, new ones
grow in their place.
But if forest is totally cut down to get land for construction of buildings, it
is lost forever.
Some other examples are fresh water, fertile soil, vegetation, wildlife, etc.
b) Non-renewable resources: The resources, which cannot be replaced after
the use, are known as non-renewable resources.
These include minerals (copper, iron etc.), fossil fuels (coal, oil etc.), wildlife
species (rare plants and animals) belong to this category.
Amongst the earth`s resources, (i) Forests (ii) Water (iii) Minerals (iv) Food
(v) Energy and (vi) Land resources contribute significantly to human welfare
The causes of deforestation
Strategies to reduce deforestation
Some important strategies could be implemented to reduce deforestation
as,
Reduce population growth and increase per capita incomes
Reducing emissions from deforestation and forest degradation
Increase the area and standard of management of protected areas
Increase the area of forest permanently reserved for timber production
Increase the distinguished and actual value of forests
Promote sustainable management
Increase area of forest plantation
Strengthen government and non-government institutions and policies
Policy, legislative and regulatory measures enforcement and compliance
Water
Floods-
Causes of Floods
What is a drought?
A drought is defined as "a period of abnormally
dry weather sufficiently prolonged for the lack of
water to cause serious hydrologic imbalance in the
affected area." -Glossary of Meteorology (1959).
In India, droughts mainly occur due to,
i) delay in the onset or failure of monsoons ii) large inconsistency of
monsoon rainfall, and iii) long break in monsoon.
According to the norms of Indian Meteorological Department, a
meteorological subdivision is considered to be drought affected if
its total seasonal rainfall is less than 75% of the normal.
Prolonged meteorological drought causes hydrological drought.
Drought is classified as “severe” if percent departure is more than
50% and moderate if it is 25-50%.
Drought is a sneaking disaster, whose beginning and end are
difficult to determine. The effects of drought accumulate slowly
over significant period of time and may extend for major events.
About one sixth of the geographical area of India are with 12%
of the population is drought prone; the areas that obtain an
annual rainfall up to 60 cm are the most prone.
Most of the drought prone areas are in arid, semi arid, and sub
humid regions. Constant drought affected areas are impounded
to West Rajasthan and Kutch in Gujarat.
Nearly 57% of Rajasthan and 32% of Gujarat falls in arid zone.
Nearly 61% of Maharashtra is semi arid.
Natural Disasters are massive economic burdens on India.
A scheme called Calamity Relief Fund (CRF) has been
comprised for each state to undertake relief and treatment
measures.
Conflicts over water (International and Inter State)
International conflict
In 2012,Violence erupts in the latest event in the dispute between Pakistan and India over
the waters of the Indus Basin.
Pakistani militants attack and sabotage water systems, flood protection works, and dams
in the Wular Lake region of northern Kashmir.
They attack engineers and workers and detonate explosives at the unfinished Tulbul
Navigation Lock/Wular Dam.
Pakistan claims the new dam violates the Indus Water Treaty by cutting flows to
Pakistan.
Inter state conflict
In 2016,At least 18 people are killed and 200 injured after the Indian Army intervenes to
reopen the Munak canal, which supplies New Dehli with three-fifths of its freshwater
supply.
The canal is shut down by economic protests in Harayana state.
Sabotage of the canal left more than 10 million people in India's capital, Delhi, without
water.
Energy resources
An energy resource is something that can produce heat, power life, move
objects, or produce electricity.
The Matter that stores energy is called a fuel.
Human energy consumption has grown steadily throughout human
history.
Early humans had modest energy requirements, mostly food and fuel for
fires to cook and keep warm.
In today's society, humans consume as much as 110 times as much energy
per person as early humans.
In any event, the exploitation of all energy sources (with the possible
exception of direct solar energy used for heating) ultimately relies on
materials on planet Earth.
The energy can be divided in to two types depending on its sources as
renewable and non- renewable energy sources.
Types of energy resources
Renewable energy
sources
Renewable energy uses
energy sources that are
continually replenished
by nature, the sun, the
wind, water, the Earth’s
heat, and plants.
Renewable energy
technologies turn these
fuels into usable forms
of energy most often
electricity, but also heat,
chemicals, or mechanical
power.
Non-renewable energy sources
A non-renewable natural resource is one that has specific conditions
that made them (like fossilized plant matter converting into coal),
and can take many generations to reproduce.
Sometimes the conditions are not likely to occur again so they are
limited in supply and once used cannot be re-generated within a
short span of time.
Non-renewable sources exist in the form of natural gas, oil, coal
and nuclear power.
There are many countries, which have recorded significant
reduction of these sources and are currently suffering from the side
effects of drilling these energy reserves from deep underground
e.g. China and India.
Growing energy needs
At present, one of the main problems of our society is the energy crisis and related
environmental crisis,
We need more and more energy to sustain our way of living, but energy (like water) is
not at hand, not when we need, not in the desired form, and its usage generates harmful
wastes.
The water problem is similar in the sense that both, energy and water, are not consumed
(only used; their amount on Earth is constant), but we require water and energy of good
quality (potable water, concentrated energy), and we reject them as waste (sewage, and
fumes), relaying on the environment to recycle them.
We leave aside metabolic energy (to feed us and our animals), and other energy services
of use by mankind.
Growth in the world's population and economy, coupled with rapid urbanization, will
result in a substantial increase in energy demand over the coming years.
The United Nations (UN) estimates that the world's population will grow from 7.6 billion
in 2017 to 9.7 billion by 2050.
Between 2005 and 2030, energy consumption is expected to increase by 50 %, with the
bulk of the demand coming from developing countries.
Case studies
Kasai village, Madhya Pradesh (biomass for electricity)
Kasai is a remote, forest-fringe adivasi (tribal) village with 55 households and a population of 392.
The village is endowed with abundant biomass resources in the form of wood (from forests and farmland), crop
residues, cattle dung and oil seeds.
Since 2005, the Government has been supporting a project in the village to generate
electricity from a small, 10 KW biomass plant.
Although the government funded 100% of the capital costs, the project is being managed by
the local community, with some technical support from the local Forest Department.
For instance, villagers are responsible for gathering biomass for the plant and collecting
Rs.120 a month from each household to meet the plant’s operating and maintenance costs.
The plant generates all the lighting for households, school and streets, has enabled music
systems and television to be installed in the village for entertainment, and supplies electricity
for a flour mill, water pumping and a milk-chilling unit.
At this point, traditional biomass (dung, wood and charcoal) continues to be used for cooking and heating
purposes.
The existing system could be possibly modified to ensure that gas is supplied for cooking purposes too.
This would help avoid the respiratory illnesses caused by burning traditional biomass indoors.
Model Questions
1. Describe in details renewable energy sources.
2. Add a note on Non-renewable energy resources.
3. Explain Land degradation.
4. Discuss the causes of soil erosion.
5. Explain desertification.
6. What are the impact of mining on environment and forest?
7. Explain that, why alternative energy sources are important?
8. Write a note on droughts.
