2. Our Environment
Our environment is everything that surrounds us- from the
trees, mountains, roads, buildings, things and even people. It is
a combination of both natural and human-made elements.
These elements are divided into two
types: Biotic and Abiotic. Biotic elements are all the living
organisms. Abiotic elements include all the non-living things.
Natural Environment
Everything that is not human-made comes under natural
environment. Land, air, water, plants and animals all comprise the
natural environment. Let us learn about the different domains of
the natural environment. These are the lithosphere, hydrosphere,
atmosphere and biosphere.
3. . The lithosphere is the solid crust or the hard top layer of the
earth. It is made up of rocks and minerals and covered with a
thin layer of soil. The lithosphere is an irregular surface with
mountains, plateaus, plains, valleys, landforms, etc. It is the
domain that provides us with forests, grasslands for grazing,
land for agriculture and housing. It is also a source of minerals
Hydrosphere is the domain of water. It comprises of the
various sources of water and different types of water bodies
like rivers, lakes, seas, oceans, estuaries, etc. It is essential for
all living organisms.
The atmosphere is the thin layer of air that surrounds the
earth. It is held by the gravitational force of the earth. The
Atmosphere protects us from the harmful UV rays from the sun
by blocking them out. It contains a number of gases like
oxygen, which is essential for life, dust and water vapour.
Changes in atmosphere bring changes in weather and climate.
4. All life makes up the biosphere. It is the zone of the earth
where land, water and air interact with each other to
support life.
5. What is ecosystem? Write briefly about its components and their interdependence.
1) All the plants and animals in an area are interdependent and
interrelated to each other in their physical environment, thus,
forming an ecosystem. Ecosystem is a system of
interdependence comprising the physical environment and the
organisms living within.
(ii) Plants, animals, human beings and the environment are the
components of ecosystem. Plants are the main natural
component on the earth which can use the sun's energy to
prepare food. Plants are the backbone of the natural resources
of the country.
(iii) The nature of plants in an area, to a large extent, determines
the animal life of that area. When the vegetation is altered, the
animal life also changes.
(iv) Human beings are also an integral part of the ecosystem.
They utilize the vegetation and wildlife. All the living beings on
the earth are dependent on plants directly or indirectly.
6. The term ecosystem was given by Tansley, and is made up of
two words 'eco' and 'system'. 'Eco' implies the environment
and the 'system' implies an arrangement of its components ,so
related as to form a whole unit. The most popular definition of
ecosystem is "the grouping of interdependent populations and
their related environment, which comprise a self-sustaining
system within the living world". An ecosystem may be of any
size. It may be very large, like the whole globe that can be
taken to comprise a single ecosystem. On the other end, this
system can be very small of the size of rain puddle. But these
two extreme sizes of the ecosystem are very difficult to
handle. Most of the ecosystems are of intermediate size. We
generally study our globe by making its artificial subdivisions
into units of smaller ecosystems.
7. Types of Ecosystems Broadly the ecosystem can be
divided into two categories: Natural and Man-
made
. I) Natural ecosystem: These types of ecosystems operate
themselves under natural conditions and are further divided
into two categories: -
a) Terrestrial: For example forest, grassland, desert etc.
b) Aquatic: It may be again of two types:
i) Freshwater: It may be running water system like spring,
stream or river or static water system like water of lake,
ponds, puddles, ditch, swamp etc. I
ii) Marine: It consists of deep bodies such as oceans, seas,
or estuaries.
8. ii) Man-made ecosystem:
These are artificial ecosystems managed by man, such as
cropland, aquarium, garden and dam etc. These ecosystems
may be of different sizes. But you must keep in your mind that
these ecosystem are simply separated from each other with
time and space, but functionally they are linked with each
other, forming an integrated entity. There no functional
boundary between them.
9. STRUCTURE OF ECOSYSTEM
On the basis of its structure and function, ecosystem has
bee11 defined as "any unit that includes all the organisms i.e.
the communities in a given area, interacting with the physical
environment so that a flow of energy gives rise to clearly
defined tropic structure, biotic diversity and material cycles
i.e. exchange of material between living and non-living
components within the system”
From structural point of view an ecosystem has
two major components:
a) A biotic Components (i.e. non-living
components),
b) b) Biotic Components (i.e. living components).
10. A biotic Components (Non-living)
I) The basic elements (such as phosphorous, sulphur.
carbon, nitrogen, hydrogen etc.) and compounds (such as
chlorophyll and organic materials as proteins,
carbohydrates, lipids etc.) present in the environment;
and
ii) The climate of the given region, such as temperature,
rainfall, wind etc.
Biotic Components (Living)
Included here are all the living organisms of the
environment. From the functional point of view, an
ecosystem has two types of biotic components.
11. Autotroph component: (Auto means self and troph means
nourishing). Seafood producing biotic species is called
autographs. They are capable of fixing sunlight energy and
produce their own food from simple inorganic substances
through the process of photosynthesis. Hence they are also
called producers. This component is mainly constituted by
green plants including photosynthetic bacteria
. Based on the size, autographs are of two types:
Micro producer (microscopic): Which are smaller in size such as
Phytoplankton, Algae, etc.,
' Macro producer (macroscopic): Which are bigger in size like
green plants, grasses, crops, etc.
12. Herbivores: Those animals which feed on plants are
called herbivores e.g. rabbit, rat, cow etc.
Carnivores or predators: Those animals which feed on
other animals are called carnivores e.g. lion, tiger, fox,
vulture etc.
Omnivores: Those animals which feed on both plants
and animals are called omnivores e.g. man.
saprotroph: Animals, which feed on decaying organic
materials are called saprotroph examples being
microorganisms and fungi.
13. Like autographs heterotrophs are also categorized as:
Microconsumer: They are popularly known as decomposers.
These I decomposers are saprophages or saprophytes
(heterotrophic organism) which I break down the complex
compounds of the dead organisms, absorb some of the
decomposed products, and release simple substances usable
by the producers. Microorganisms also produce growth-
promoting and growth-inhibiting substances that are
important in regulating the metabolism of the ecosystem as a
whole
Macroconsumers: All the herbivores, carnivores and
omnivores come under I this category. Herbivores are also
known as primary consumers.
14. The trophic structure of an I ecosystem is one kind of
producer-consumer arrangement, where each food level is
known as "trophic level". In a food chain each level of
producer, primary consumer, secondary consumer, tertiary
consumer or decomposer is a trophic level.
When all the trophic levels are linked they form a food
chain. But while assigning the tropic level of any species
always keep in mind that the tropic level is not fixed for
any species since any given species may utilize more than
one level. For example human beings are both plant and
animal eaters. So it can occupy both the second as well as
third tropic level. The number of stages does not usually
exceed four and the number of organisms diminishes
rapidly with increase in tropic level .
15. FOOD CHAIN The scheme of feeding relationship that unites the
members of a biological community is shown in the form of food
chain. It is a sequential arrangement of species based on their food
habits i.e. eating and being eaten away by others in turn. The entire
food chain starts with the producer followed by consumers of
different levels in a sequential order. For example
, a food chain in a grassland ecosystem starts with various types of
grass and forbs (the producers). The grasses are eaten by
grasshoppers (first order consumer), which in turn are eaten by
frog (second order consumer), the frog is eaten by the snake (third
order consumer), and the snake by the hawk (fourth order
consumer). Similarly in the pond ecosystem the food chain order is
represented as: phytoplankton -+ water Jens -+ small fish -+ bigger
fish -+ larger animals and so on. In nature, we generally distinguish
two types of food chains: Grazing and Detritus food chain.
16. Grazing Food Chain This type of chain starts from living green
plants and moves to grazing herbivores and on to carnivores, and so
on. This type of food chain is directly dependent on an influx of the
solar radiation. The above discussed grassland and pond ecosystems
are examples this type of food chain.
Detritus Food Chain 'This type of food chain starts from dead organic
matter into microorganisms and the organisms feeding on detritus
(detritivores) and their predators. Such ecosystems are less dependent on
the direct solar radiation. These chiefly depend on the influx of the organic
matter produced in another system. This type of food chain operates in
decomposing the accumulated litter. Thus we can treat it as nature's in-built
system to clean up the environment.
But under natural conditions, the linear arrangement of the food chain
hardly occurs. Mostly it is interconnected. A species may occupy more
than one trophic level during its life cycle or in response to changes in
availability of food. For instance many diptera, in adulthood suck both
plant and animal juices. Therefore, the system of feeding relationship
often resembles a web rather than a chain.
17. This can be well understood by the following example. In
grazing food chain of grassland, which we have discussed
above, in the absence of rabbit, grasses may be eaten by the
mouse. The mouse in turn may be directly eaten by a hawk or
by a snake first and a hawk then consumes snake. Thus,
alternatives are found which altogether constitute some sort
of interlocking pattern called the food web.
Grass (eaten by) + Grasshopper (eaten by) + Hawk
Grass (eaten by) -+ Grasshopper (eaten by) + Snake (eaten by) +
Hawk
Grass + (eaten by) Rabbit + (eaten by) Hawk (or any other predator
like vulture, fox or even man)
Grass + (eaten by) mouse + (eaten by) Hawk Grass -+ (eaten by)
mouse + (eaten by) snake- Hawk
Grass + (eaten by) Grasshopper+ (eaten by) Frog + (eaten by)
Snake + (eaten by) Hawk
18. Man and environment : a symbiotic dependencies
Our environment means our physical surroundings and the
characteristics of the place in which we live. It also refers to the
wider natural world of land, sea and atmosphere. Humans have
been interacting with their environment since people first walked
the Earth. For example, humans have been cutting down forests to
clear land to grow crops for centuries and by doing so we have
altered the environment. Conversely, the environment affects us in
many different ways as well. A simple example is the way we change
our clothes in response to cold or hot weather. In this section we will
introduce some of the ways in which humans influence their
environment and how the environment influences us, both
positively and negatively.
A good climate, accessible clean water, fertile soil, etc. are aspects of
the physical environment that enable people to live and thrive.
However, harsh environments, such as a very hot climate, limited
water and infertile land, make it more difficult for people to survive.
19. We depend on food and water for survival and we need energy
for many different purposes, from domestic cooking through to
major industrial processes. Our clothes, transport, buildings,
tools and all other items we use require many different
resources for their production. Let’s take a simple example.
Think about the resources that have been used to produce a
notebook of the type you may be using right now as you study
this Module. Manufacturing the paper needed raw materials of
wood and water as well as energy for the production process.
The trees that supplied the wood required soil, water and land
to grow on. There may be ink or metal staples or other
components in your notebook that were made from other types
of resources. Our need for resources is vast and it is growing as
the population increases and consumption per person increases
with socio-economic progress. Depletion of natural resources by
extraction and exploitation is especially of concern for non-
renewable resources
20. Environmental Education
environmental education is a process that allows individuals to explore environmental
issues, engage in problem solving, and take action to improve the environment. As a
result, individuals develop a deeper understanding of environmental issues and have
the skills to make informed and responsible decisions.
The components of environmental education are:
•Awareness and sensitivity to the environment and environmental challenges
•Knowledge and understanding of the environment and environmental challenges
•Attitudes of concern for the environment and motivation to improve or maintain
environmental quality
•Skills to identify and help resolve environmental challenges
•Participation in activities that lead to the resolution of environmental challenges.
21. Efforts to define environmental education as a specific endeavour began in the
1960s. They were given international support at the United Nations conference
on the Human Environment held in Stockholm in 1972, where participating
governments recommended that it be recognised and promoted on an
international scale through the United Nations. One of the initial tasks was to
develop some consensus on what environmental education could and should
become, and to assist governments in implementing relevant programs as soon
as practicable. Two major conferences, supported by regional meetings of
experts, were hosted by the newly formed UNESCO-UNEP International
Environmental Education Programme. The purpose of the first (Belgrade, 1975)
was to draft concepts and a vision for environmental education. The second, an
Intergovernmental Conference on Environmental Education (Tbilisi, 1977),
formally approved the scope and action plans put forward from the previous
conference. The provisions of the 'Tbilisi Declaration on the role, objectives and
characteristics of environmental education', appended to this document,
remain in wide international use and have sustained their role as a guiding
influence over the past two decades. Other major milestones include:
22. •The IUCN World Conservation Strategy (1980) suggested requirements
for human survival and prosperity, putting forward the conservationist
concept of sustainable development.
•Our Common Future (1988) was the name of the report published by the
World Commission on Environment and Development, chaired by the
Prime Minister of Norway, Mrs Brundtland. It emphasised the relationship
between the under-developed nature of parts of the world, and existing
social and environmental problems. The report is a survey of the planet's
health, presenting the problems of atmospheric pollution, desertification,
over-population, over-consumption, water shortages, poverty and under-
development.
•Agenda 21 (1992) The United Nations Conference on Environment and
Development in Rio de Janeiro established further strategies for a
sustainable future. Chapter 36 of the action plan adopted by the
Conference, Agenda 21, focused on public education, awareness and
training, which confirms the role of education and the importance of
positioning environmental education in the perspective of sustainable
development.
23. UNESCO Thessaloniki Declaration (1997), Educating for a Viable
Future: a multidisciplinary vision for concerted action sought to
further clarify the concept of education for sustainable
development. It presented sustainability as an ethical and moral
imperative and the objective to which education should devote
itself as an instrument of choice. Education is described as an
ongoing process aimed at developing the capability of adapting
to rapid changes in the world, but first and foremost as a
process of transmitting knowledge and information to make the
public understand the problems and to stimulate awareness.
24. Objectives of environmental education .
(a) Creating the awareness about environmental problems among
people.
(b) Imparting basic knowledge about the environment and its allied
problems.
(c) Developing an attitude of concern for the environment.
(d) Motivating public to participate in environment protection and
environment improvement.
(e) Acquiring skills to help the concerned individuals in identifying
and solving environmental problems.
(f) Striving to attain harmony with Nature.
25. Environmental education discipline has multiple and multilevel
scopes. This study is important and necessary not only for
children but also for everyone. The scopes are summarized as
follows:
The study creates awareness among the people to know about various
renewable and nonrenewable resources of the region. The endowment or
potential, patterns of utilization and the balance of various resources
available for future use in the state of a country are analysed in the study
. 2. It provides the knowledge about ecological systems and cause and effect
relationships.
3. It provides necessary information about biodiversity richness and the
potential dangers to the species of plants, animals and microorganisms in
the environment.
4. The study enables one to understand the causes and consequences due
to natural and induced disasters (flood, earthquake, landslide, cyclones etc.,)
and pollutions and measures to minimize the effects.
5. It enables one to evaluate alternative responses to environmental issues
before deciding an alternative course of action.
6. The study enables environmentally literate citizens (by knowing the
environmental acts, rights, rules, legislations, etc.) to make appropriate
judgments and decisions for the protection and improvement of the earth.
26. 7. The study exposes the problems of over population, health, hygiene, etc. and the
role of arts, science and technology in eliminating/ minimizing the evils from the
society.
8. The study tries to identify and develop appropriate and indigenous eco-friendly
skills and technologies to various environmental issues.
9. It teaches the citizens the need for sustainable utilization of resources as these
resources are inherited from our ancestors to the younger generation without
deteriorating their quality.
10. The study enables theoretical knowledge into practice and the multiple uses of
environment.
ENVIRONMENTAL EDUCATION The need to protect the environment hence the
rationales for environmental education arise as a result of the following: 1.
Environment is the basis of all life and therefore deserves proper care and
management. 2. If the environment is threatened on a continuous basis, numerous
problems which would constitute a danger to human existence could arise. 3. The
environment is part of our cultural heritage which should be handed down to
prosperity. 4. Some resources of the environment are not easily replaceable and
should be managed on a sustainable basis, to prevent the extinction of certain
components of the environment such as plants and animals. 5. There is need to
enhance the sanity and aesthetic quality of our environment in order to promote
healthy living. 6. The environment is part of nature and needs to be preserved for
its own sake.
Nature
27. RATIONALE FOR ENVIRONMENTAL EDUCATION The rationale for
environmental education can be summarized as the following: 1. A major
goal of environmental education in India as entrenched in National Policy on
Education is the provision of the expertise that can utilize scientific
knowledge towards the preservation and solution of environmental
problems. Knowledge about the changes that have altered the environment -
land, water, weather, and vegetation; social, cultural and political
environment are essential components of environmental education.
Consequently, the general public should be equipped with all these to be
able to solve the problems of the environment. 2. India’s socio-economic
development (like any other less developed country) is firmly rooted on the
exploitation of the natural resources in our environment. Land, water, forest
and other mineral resources utilization is the dominant feature of rural
economy with agriculture the driving force. Uncontrolled and improper
exploitation of these resources have implications on the environment causing
disruption in the living standard, starvation, displacement and human
suffering. Environmental Education is therefore necessary to create
awareness of the causes and effects of these problems vise: food and water
scarcity, pollution, outbreak of epidemics and natural disaster such as flood,
erosion and desert encroachment.
28. Environmental education is needed to foster international co-operation and
understanding. The developed countries rely on the high technology for the
exploitation of natural resources while developing countries like India totally
depend on agriculture, forestry and the mineral resources thereby leading to
intensive and over-exploitation of the natural resources and these have
serious implications on the resources. 4. Public enlightenment on the impact
of government policies on local environment should be useful both to the
government and the local people. 5. Awareness of such global environmental
issues is an essential component of environmental education which ordinary
citizen should be aware of. 6. Environmental education for the over-all social
and economic emancipation of women and children. These form a
substantial percentage in the utilization of natural resources especially at the
rural setting. 7. Environmental education is very essential for the lack of it.
Environmental Education is virtually a new thing in this part of the world. 8.
Environment education is also very essential for our survival on earth. The
natural resources and cultural heritage need to be protected not only for this
generation but for future generation.
