Natural Resources
Our environment provides us with a variety of
goods and services necessary for our day to day
lives. These natural resources include, air, water,
soil, minerals, along with the climate and
solar energy, which form the non-living or ‘abiotic’
part of nature. The ‘biotic’ or living parts
of nature consists of plants and animals, including
microbes. Plants and animals can only survive
as communities of different organisms, all
closely linked to each in their own habitat, and
requiring specific abiotic conditions. Thus, forests,
grasslands, deserts, mountains, rivers, lakes
and the marine environment all form habitats
for specialised communities of plants and animals
to live in. Interactions between the abiotic
aspects of nature and specific living organisms
together form ecosystems of various types.
Many of these living organisms are used as our
food resources. Others are linked to our food
less directly, such as pollinators and dispersers
of plants, soil animals like worms, which recycle
nutrients for plant growth, and fungi and termites
that break up dead plant material so that
micro-organisms can act on the detritus to reform
soil nutrients.
History of our global environment: About
ten thousand years ago, when mankind changed
from a hunter-gatherer, living in wilderness areas
such as forests and grasslands, into an agriculturalist
and pastoralist, we began to change
the environment to suit our own requirements.
As our ability to grow food and use domestic
animals grew, these ‘natural’ ecosystems were
developed into agricultural land. Most traditional
agriculturists depended extensively on rain,
streams and rivers for water. Later they began
to use wells to tap underground water sources
and to impound water and created irrigated land
by building dams. Recently we began to use fertilizers
and pesticides to further boost the production
of food from the same amount of land.
However we now realize that all this has led to
several undesirable changes in our environment.
Mankind has been overusing and depleting
natural resources. The over-intensive use of land
has been found to exhaust the capability of the
ecosystem to support the growing demands of
more and more people, all requiring more intensive
use of resources. Industrial growth,
urbanisation, population growth and the enormous
increase in the use of consumer goods,
have all put further stresses on the environment.
They create great quantities of solid waste. Pollution
of air, water and soil have begun to seriously
affect human health.
Changes in land and resource use:
During the last 100 years, a better
health care delivery system and an
improved nutritional status has led to
rapid population growth,
especially in the developing
countries. This phenomenal
rise in human
numbers has, in the recent
past, placed great demands
on the earth’s natural resources. Large
stretches of land such as forests, grasslands and
wetlands have been converted into intensive agriculture.
changes have brought
about dramatic alterations in land-use patterns
and rapid disappearance of valuable natural ecosystems.
The need for more water, more food,
more energy, more consumer goods, is not only
the result of a greater population, but also the
result of over-utilization of resources by people
from the more affluent societies, and the affluent
sections of our own.
Industrial development is aimed at meeting
growing demands for all consumer items. However,
these consumer goods also generate waste
in ever larger quantities. The growth of industrial
complexes has led to a shift of people from
their traditional, sustainable, rural way of life to
urban centers that developed around industry.
During the last few decades, several small urban
centers have become large cities, some have
even become giant mega-cities. This has increased
the disparity between what the surrounding
land can produce and what the large
number of increasingly consumer-oriented
people in these areas of high population density
consume. Urban centers cannot exist without
resources such as water from rivers and
lakes, food from agricultural areas, domestic
animals from pasture lands and timber, fuel
wood, construction material and other resources
from forests. Rural agricultural systems are dependent
on forests, wetlands, grasslands, rivers
and lakes. The result is a movement of natural
resources from the wilderness ecosystems and
agricultural sector to the urban user. The magnitude
of the shift of resources has been increasing
in parallel with the growth of industry and
urbanisation, and has changed natural landscapes
all over the world. In many cases, this
has led to the rapid development of the urban
economy, but to a far slower economic development
for rural people and serious impoverishment
of the lives of wilderness dwellers. The
result is a serious inequality in the distribution
of resources among human beings, which is both
unfair and unsustainable.
Earth’s Resources and Man: The resources on
which mankind is dependent are provided by
various sources or ‘spheres’.
1) Atmosphere
• Oxygen for human respiration (metabolic requirements).
• Oxygen for wild fauna in natural ecosystems
and domestic animals used by man as food.
• Oxygen as a part of carbon dioxide, used
for the growth of plants (in turn are used
by man).
The atmosphere forms a protective shell over
the earth. The lowest layer, the troposphere,
the only part warm enough for us to survive in,
is only 12 kilometers thick. The stratosphere is
50 kilometers thick and contains a layer of
sulphates which is important for the formation
of rain. It also contains a layer of ozone, which
absorbs ultra-violet light known to cause cancer
and without which, no life could exist on
earth. The atmosphere is not uniformly warmed
by the sun. This leads to air flows and variations
in climate, temperature and rainfall in different
parts of the earth. It is a complex dynamic system.
If its nature is disrupted it affects all mankind.
Most air pollutants have both global and
regional effects.
Living creatures cannot survive without air even
for a span of a few minutes. To continue to support
life, air must be kept clean. Major pollutants
of air are created by industrial units that
release various gases such as carbon dioxide,
carbon monoxide and toxic fumes into the air.
Air is also polluted by burning fossil fuels. The
buildup of carbon dioxide which is known as
‘greenhouse effect’ in the atmosphere is leading
to current global warming. The growing
number of scooters, motorcycles, cars, buses and
trucks which run on fossil fuel (petrol and diesel)
is a major cause of air pollution in cities and
along highways.
Air pollution leads to acute and chronic respiratory
diseases such as various lung infections,
asthma and even cancer.
2) Hydrosphere
• Clean water for drinking (a metabolic requirement
for living processes).
• Water for washing and cooking.
• Water used in agriculture and industry.
• Food resources from the sea, including fish,
crustacea, sea weed, etc.
• Food from fresh water sources, including
fish, crustacea and aquatic plants.
• Water flowing down from mountain ranges
harnessed to generate electricity in hydroelectric
projects.
The hydrosphere covers three quarters of the
earth’s surface. A major part of the hydrosphere
is the marine ecosystem in the ocean, while only
a small part occurs in fresh water. Fresh water
in rivers, lakes and glaciers, is perpetually being
renewed by a process of evaporation and rainfall.
Some of this fresh water lies in underground
aquifers. Human activities such as deforestation
create serious changes in the hydrosphere. Once
land is denuded of vegetation, the rain erodes
the soil which is washed into the sea.
Chemicals from industry and sewage find their
way into rivers and into the sea. Water pollution
thus threatens the health of communities
as all our lives depend on the availability of clean
water. This once plentiful resource is now becoming
rare and expensive due to pollution.
3) Lithosphere
• Soil, the basis for agriculture to provide us
with food.
• Stone, sand and gravel, used for construction.
• Micronutrients in soil, essential for plant
growth.
• Microscopic flora, small soil fauna and fungi
in soil, important living organisms of the
lithosphere, which break down plant litter
as well as animal wastes to provide nutrients
for plants.
• A large number of minerals on which our
industries are based.
• Oil, coal and gas, extracted from underground
sources. It provides power for vehicles,
agricultural machinery, industry, and
for our homes.
The lithosphere began as a hot ball of matter
which formed the earth about 4.6 billion years
ago. About 3.2 billion years ago, the earth
cooled down considerably and a very special
event took place - life began on our planet. The
crust of the earth is 6 or 7 kilometers thick and
lies under the continents. Of the 92 elements in
the lithosphere only eight are common constituents
of crustal rocks. Of these constituents, 47%
is oxygen, 28% is silicon, 8% is aluminium, 5%
is iron, while sodium, magnesium, potassium
and calcium constitute 4% each. Together,
these elements form about 200 common mineral
compounds. Rocks, when broken down,
form soil on which man is dependent for his
agriculture. Their minerals are also the raw material
used in various industries.
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