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Unit II - ECOSYSTEMS AND BIODIVERSITY
Concept of an Ecosystem
An ecosystem is the ecological unit consisting of biotic factors (living) and abiotic factors
(non-living) in a specific area. For example forest, Grassland desert aquatic etc.
An ecosystem in constituted by the living community of plants and animals in any area
with the non-living components of environment such as air, water and soil.
An ecosystem is a community of different species interacting with each other and with nonliving environment, exchanging energy to form a stable self supporting system.
An ecosystem is a complex and dynamic system, constantly in motion. Nutrients are
continually recycled with ecosystem while energy flows through it. The size of the ecosystem is
variable. It may be large as ocean / forest and smaller as aquarium even as drop of pond water.
Types of Ecosystem
On the basis of interference and non-interference by man, there exists two types of
ecosystem.
1.
2.
Natural ecosystem
Artificial ecosystem
Characteristics of Ecosystem

It is a structural and functional unit of ecology

Its structure is related to species diversity i.e. more complex ecosystem have high species
diversity and simple ecosystem have low diversity.

Functions of ecosystem are related to energy flow and cycling of material involved and
within ecosystem.

Ecosystem mature as we pass from less complex to more complex structure i.e. early stage
has excess potential energy and relatively high energy flow per unit biomass than later stages. It
reduces at energy stage.

Alterations in environment represent selective pressures upon populations to which it must
adjust, those which are unable to adjust must disappear i.e. survival at fittest.

Environment and energy fixation in any ecosystem is limited and constant be exceeded
without serious undesirable effects.
Structure and Function of an Ecosystem

The structure of an ecosystem indicates it’s components and their interdependency for
growth and survival.

An ecosystem has two types of components.
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1.
2.
Abiotic component (non-living)
Biotic component (living)
Abiotic Components
It determines the type of organisms can live in specific area. Abiotic components can be
physical components or chemical components.
Physical Components
It usually includes sunlight, water, soil, temperature etc. These are necessary growth of
species.
Sunlight – Necessary for photosynthesis.
Water – Essential for living things.
Temperature – Necessary for survive.
Soil – Provides base and nutrients.
Biotic Components
Biotic components are living components of the ecosystem. It includes – plants, animals,
fungi, bacteria and there living components.
The biotic components of an ecosystem can be categorized into three categories.



Producers or autotrophs.
Consumer of heterotrophs.
Decomposers or detrivores.
Energy flow in Ecosystem
The energy needed for the function of ecosystems comes from an external source, the sun.
The solar energy is transformed into chemical energy by using photo-synthesis. This chemical
energy is nothing but carbohydrates and oxygen.
A part of chemical energy is utilized by the produces (plants) for their growth and
remaining energy is transferred to consumers. The decomposer utilizes the energy with consumer
producing inorganic nutrient. It is again used by producer to produce food for consumer.
Biogeochemical Cycle
In an ecosystem the cycling of nutrient involves both biotic and abiotic components. The
biochemical cycle involves
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1.
2.
3.
4.
5.
Hydrological cycle (water cycle)
Oxygen cycle
Nitrogen cycle
Carbon cycle
Phosphorous cycle
Hydrologic Cycle
The water cycle, also known as the hydrologic cycle, describes the continuous movement of water
on, above, and below the surface of the Earth. Since the water cycle is truly a "cycle," there is no
beginning or end. Water can change states among liquid, vapor, and ice at various places in the
water cycle. Although the balance of water on Earth remains fairly constant over time, individual
water molecules can come and go.
Description
The sun, which drives the water cycle, heats water in the oceans. Water evaporates as vapor into
the air. Ice and snow can sublimate directly into water vapor. Evapotranspiration is water
transpired from plants and evaporated from the soil. Rising air currents take the vapor up into the
atmosphere where cooler temperatures cause it to condense into clouds. Air currents move clouds
around the globe, cloud particles collide, grow, and fall out of the sky as precipitation. Some
precipitation falls as snow and can accumulate as ice caps and glaciers, which can store frozen
water for thousands of years. Snow packs can thaw and melt, and the melted water flows over land
as snowmelt. Most precipitation falls back into the oceans or onto land, where the precipitation
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flows over the ground as surface runoff. A portion of runoff enters rivers in valleys in the
landscape, with streamflow moving water towards the oceans. Runoff and groundwater are stored
as freshwater in lakes. Not all runoff flows into rivers. Much of it soaks into the ground as
infiltration. Some water infiltrates deep into the ground and replenishes aquifers, which store huge
amounts of freshwater for long periods of time. Some infiltration stays close to the land surface
and can seep back into surface-water bodies (and the ocean) as groundwater discharge. Some
groundwater finds openings in the land surface and comes out as freshwater springs. Over time, the
water returns to the ocean, where our water cycle started.
The Sulphur Cycle
Sulphur and its compounds are not found to any great extent in the atmosphere but it is
involved in a complex geochemical cycle. The major reservoir for sulphur is the lithosphere.
The decay of dead organic matter by aerobic bacteria gives rise to hydrogen sulphide, H2S,
gas in the atmosphere, which is rapidly oxidized to SO4 in the presence of water and oxygen. The
reaction takes a few hours to several days to occur in the atmosphere and probable takes place on
aerosol droplets catalysed by metal ions.
Photosynthesis
It is a complex redox process by which plants, algae and certain bacteria, using the energy
of sunlight, convert carbon dioxide and water into carbohydrates (sugar) and dioxygen. The
catalysts used in plants are the chlorophyll pigments, carotenoids and the phycoblins. The
pigments absorb light and help to convert it into chemical energy via the formation of new
chemical bonds. The overall reaction can be simply represented by
Chlorophyll
CO2(g) + H2O (1) -----------------------> [CH2O] (aq) + O2(g)
Sunlight energy
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It is the main way foodstuffs are produced for the higher animals, atmospheric dioxygen is
replenished and energy obtained from the sun is stored. Plants that can photosynthesis are therefore
referred to as the primary producers in the food chain. All other organisms that feed on plants in
order to use their organic compounds in respiration and as an energy source are called consumers.
Food Chains
Any ecosystem is mainly driven by the flow of energy in it. In an ecosystem energy is
present in different forms.
Transfer of energy from the source in plants through series of organisms with repeated
stages of eating and being eaten is known as food chain i.e. transfer of flow of energy from one
tropic level to other in succession.
Types of Food Chain
1.
Grazing food chain 2) Parasitic food chain and 3) Detritus food chain
Grazing food chain
It starts from green plants (producers) and ends to carnivores by passing through
herbivores. For example – grassland ecosystem, pond ecosystem.
Detritus food chain
Food chain starts from dead organisms matter of decaying animal and plant bodies to the
micro organisms then to detrivorous or saprovorous and their predator is known as Detritus food
chain.
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Fungi, bacteria, protozoa etc. which are eaten and re-eaten by group of small animals.
These animals include crabs, bivalves, Insect larvae, nematodes, grass shrimps etc. All these
animals are called detritus consumers.
Food Web
In an ecosystem there is large number of interlinked chain processes. Various food chain
processes are interconnected with each other in specific patterns. A food web is a model that
represents all possible feeding relationship among organisms of ecosystem.
Ecological Pyramid
It is used to represent the status of the ecosystem for different parameters such as food,
energy, and biomass. The types of Pyramids are
1) Pyramid of Number
2) Pyramid of Energy
3) Pyramid of Biomass
Food pyramid
It shows the food consumer profile in a food web. The base of the pyramid shows producer
the next level is primary and secondary consumer out at the apex highest or tertiary consumers.
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Pyramid of Biomass
The biomass is based on weight or biomass of the organisms in each tropic level at any
time. There is decrease in biomass from lower tropic level to the higher tropic level.
Forest Ecosystem
Forests are formed by trees, shrubs and climbers forests are renewable resources and plays
a key role in improving environment. Each forest type forms a habitat of specific community of
animal.
Forest Ecosystem has two parts
1) Abiotic and
2) Biotic
Different types of forests
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Coniferous (Ever-green forest)
Deciduous (Temperature deciduous)
Tropical rain forest
Scrub forests.
Characteristics of Forest Ecosystem
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Forest have warm climate with adequate rainfall
Forests have well defined seasons of about equal length.
Forest protects biodiversity
Forests have tall and dense trees with many wild animals within ecosystem.
The soil of forest is rich in organic matter and nutrients.
Forests grow very slowly
Forests provide various resources for human life.
Structure and Function of Forest Ecosystem
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Biotic components
The various biotic components, representatives from the three functional groups, of a
forest ecosystem are:
1) Producer Organisms
In a forest, the producers are mainly trees.
Trees are of different kinds depending upon the type of forest developed in that climate.
Apart from trees, climbers, epiphytes, shrubs and ground vegetation. Dominant species of
trees in major types of forest ecosystems are: Tectona grandis, Acer, Betula, Picea, Pine, Cedrus.
2) Consumers
In a forest, consumers are of three main types;
a) Primary Consumers
These are Herbivores which feed directly on producers. For example:
Ants, Beetles, Bugs, spiders etc. feeding on tree leaves.
Larger animals such as Elephants, Deer, giraffe etc. grazing on shoots and/or fruits
of trees.
b) Secondary Consumers
These are carnivores and feed on primary consumers. Eg: Birds, Lizards, Frogs, Snakes and
Foxes.
c) Tertiary Consumers
These are secondary carnivores and feed on secondary consumers These include top
carnivores like Lion, Tiger.
3) Decomposers
These include wide variety of saprotrophic micro- organism like; Bacteria (Bacillus Sp.,
Clostridium sp., pseudomonas. Fungi (Aspergillus sp., Ganoderma sp., Fusarium.
Actinomycetes (Streptomyces).
They attract the dead or decayed bodies of organisms & thus decomposition takes place.
Therefore, nutrients are released for reuse.
Abiotic components
These include basic inorganic & organic compounds present in the soil & atmosphere.
In addition dead organic debris is also found littered in forests.
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GRASSLAND ECOSYSTEM (TERRESTRIAL ECOSYSTEM)
Introduction
Grasslands (also called Greenswards) are areas where the vegetation is dominated
by grasses and other herbaceous (non-woody) plants.
Grasslands occupy about 24% of the earth’s surface.
Grasslands occur in regions too dry for forests and too moist for deserts.
The annual rainfall ranges between 25- 75 cm.
The principal grasslands include:
Prairies
America),Steppes (Europe & Asia) Veldts (Africa)
(Canada,
USA),Pampas
(South
The highest abundance & greatest diversity of large mammals are found in these
ecosystems. The dominant animal species include Wild horses, asses & antelope of Eurasia,
Structure and functions of Grassland Ecosystems
Biotic components
1) Producer Organisms
In grassland, producers are mainly grasses; though, a few herbs & shrubs also contribute to
primary production of biomass.
Some of the most common species
Desmodium sp., Digitaria sp.
of grasses are: Brachiaria sp., Cynodon sp.,
2) Consumers
In a grassland, consumers are of three main types;
a) Primary Consumers
The primary consumers are herbivores feeding directly on grasses. These are grazing
animals such as Cows, Buffaloes, Sheep, Goats, Deer, Rabbits etc. Besides them, numerous
species of insects, termites, etc are also present.
b) Secondary Consumers
These are carnivores that feed on primary consumers (Herbivores)
These include;-Frogs, Snakes, Lizards, Birds, Foxes, Jackals etc.
c) Tertiary Consumers
These include hawks etc. which feed on secondary consumers.
3) Decomposers
These include wide variety of saprotrophic micro- organism like: Bacteria; Fungi;
Actinomycetes.
They attract the dead or decayed bodies of organisms & thus decomposition takes place.
Therefore, nutrients are released for reuse by producers.
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and
Abiotic components
 These include basic inorganic & organic compounds present in the soil & aerial
environment.
 The essential elements like C, H, N, O, P, S etc. are supplied by water, nitrogen, nitrates,
sulphates, phosphates present in soil & atmosphere.
DESERT ECOSYSTEM
Introduction
A desert is a landscape or region that receives almost no precipitation.
Deserts are defined as areas with an average annual precipitation of less than
250 millimeters per year.
It occupies about 17 % of the earth’s surface.
Deserts are characterized by hot days & cold nights.
The deserts of the world are mainly located in the South- western United States, Mexico,
North America, Asia (Thar, Gobi, Tibet) & west Asia.
Deserts are characterized by scanty flora & fauna.
Soils of deserts often have abundant nutrients but little or no organic matter.
Sturucture and Functions of Desert Ecosystms
Biotic components
1) Producer Organisms
In a desert, producers are mainly shrubs/bushes; some grasses & a few trees.
Dominant plant species include: Succulents (water - retaining plants adapted to arid climate
or soil conditions) & hardy grasses.
Besides some lower plants such as lichens & xerophytic mosses are also present.
2) Consumer Organisms
These include animals such as insects, reptiles which are capable of living in xeric conditions
Besides some nocturnal rodents, birds & some mammalians like camel etc are also found.
3) Decomposers
Due to poor vegetation with very low amount of dead organic matter, decomposers are poor in
desert ecosystem.
The common decomposers are some bacteria & fungi, most of which are thermophillic.
Abiotic components
Due to high temperature & very low rainfall, the organic substances are poorly present in the
soil.
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AQUATIC ECOSYSTEMS
Introduction
Aquatic ecosystems deal with biotic community present in water bodies.
In terrestrial ecosystem, carbon dioxide & oxygen are present in gaseous form whereas in
aquatic ecosystem, these are available in dissolved state.
Depending upon the quality and nature of water, the aquatic ecosystem are categorized
into: Freshwater Ecosystem and Marine Ecosystem.
Freshwater Ecosystems
Freshwater ecosystems cover 0.8% of the Earth's surface and contain 0.009% of its total
water.
Freshwater ecosystems contain 41% of the world's known fish species.
Aquatic ecosystems perform many important environmental functions. For example:
They recycle nutrients, purify water, attenuate floods, recharge ground water and provide habitats
for wildlife.
Aquatic ecosystems are also used for human recreation, and are very important to
the tourism industry, especially in coastal region.
There are three basic types of freshwater ecosystems:
Lentic: slow-moving water, including Pools, Ponds, and Lakes.
Lotic: rapidly-moving water, for example Streams and Rivers.
Wetlands: areas where the soil is saturated with water or inundated for at least part
of the time
Lakes & pond Ecosystem
A pond is a place where living organisms not only live but interact with biotic & abiotic
components.
Ponds are often exposed to tremendous anthropogenic pressure which significantly affects
the system.
Lakes are usually big standing freshwater bodies.
They have a shallow water zone called Littoral zone; an open water zone where effective
penetration of solar light takes place, called limnetic zone and a deep water zone where light
penetration is negligible, called Profoundal zone.
Biotic components
1) Producer Organisms
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 It includes submerged, free floating and amphibious macrophytes (like; Hydrilla,
Utricularia, Wolfia, Azolla, Typha etc.) and minute floating and suspended lower
phytoplanktons (like; Ulothrix, Spirogyra, Oedogonium etc.)
2) Consumer Organisms
a) Primary consumers:These are zooplanktons (ciliates, flagellates, other protozoan, small
crustaceans) and benthos.
b) Secondary consumers: These are carnivores like insects and fishes feeding on herbivores
c) Tertiary consumers: These are the large fishes feeding on small fishes.
3) Decomposers Micro – organisms like bacteria, fungi and actinomyctes.
Abiotic component
 These are the inorganic as well as organic substances present in the bottom soil or
dissolved in water. In addition, to the minerals, some dead organic matter is also present.
Marine or Ocean Ecosystem
Marine ecosystems are among the Earth's aquatic ecosystems. They include: Oceans,
Estuaries and Lagoons, Mangroves and Coral reefs, the Deep sea and the Sea floor.
These are the gigantic reservoirs of water covering approximately 71% of
the Earth's surface (an area of some 361 million square kilometers).
These ecosystems are different from freshwater ecosystem mainly because of its salty
water.
The salt concentration in an open sea is usually 3.5% (35 parts per thousand (ppt)).
Dominant ions are sodium & chloride.
Average temperature of Marine ecosystem is 2-3 degree centigrade, devoid of light.
Biotic components
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1) Producers It includes phytoplanktons (diatoms, dinoflagillates), large seaweeds (mainly algae
like chlorophyceae, phaeophyceae & rhodophyceae; angiosperms like Ruppia, Zostera, posidonia
), and mangrove vegetation (like Rhizophora, Carapa etc.)
2) Consumers
a) Primary consumers: These are herbivores and feed directly on producers (Crustaceans,
Mollusks, fish etc.)
b) Secondary consumers: These are carnivorous fishes (Herring, Sahd and Mackerel)
c) Tertiary consumers: These are top carnivorous fishes (Cod, Haddock, etc.)
3) Decomposers: These are micro – organisms like bacteria, fungi
Abiotic components
 High Na, Ca, Mg and K salt concentration, variable dissolved oxygen content, light &
temperature make a unique physiochemical conditions in marine water.
Introduction to Biodiversity
Varieties of life on the earth exist over thousands of years to fulfill the needs of mankind.
For understanding the life cycle of plants and animals they must be classified and categorized
properly.
Biodiversity is defined as variety and variability of living organisms in a given assemblage.
Biodiversity covers whole life on earth.
Types of Biodiversity
1.
2.
3.
Genetic diversity
Species diversity
Ecosystem diversity
Genetic Diversity
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It is a measure of variety available for the same genes within individual species.

It is based on variation between genes i.e. functional units of hereditary information. The
genetic variability is essential for a healthy breeding population of a species.
Species Diversity
It is the number of different species of living things within an area. Species are regarded as
populations within gene flow occur under natural conditions. Member of one species, do not breed
freely with members of other species.
Ecosystem Diversity
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It rates to the variety of habitats, biotic communities and ecological processes in the
biosphere as well as the diversity within ecosystems. Diversity can be described at a number of
different levels and scales.
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Functional diversity is the relative abundance of functionally different kinds of organisms.
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Community diversity is the number sizes and spatial distribution of communities, and is
sometimes referred to as patchiness (uneven quality)
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Landscape diversity is the diversity of scales of patchiness.
Biogeographical Classification of India
India can be divided into 10 major zones based on geographic conditions, climate,
vegetation and animals. They are Trans Himalayan, Himalaya, Desert, Semiarid, Western Ghat,
Deccan peninsula, Gangetic plain, North East India, Island and Coastal areas. Every zone has a
unique ecosystem, biotic and abiotic components.
Value of Biodiversity
A rich biodiversity is the wealth of any nation. Biodiversity provides variety of
environmental survives and ecosystem essential for human life. Each organism has its own
significance in the biosphere.
The value of biodiversity is classified into various categories depending on its use such as
1.
2.
3.
4.
5.
6.
Consumptive use
Productive use
Social use
Ethical use
Aesthetic
Option value
Consumptive use
It is direct utilization of various species by the modern society. The major sources are –
food, medicinal plants, fuel etc. These products are directly supplied by biodiversity.
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Food - Seasonal fruits, vegetable, food grains, sea food, chicken, duck
Medical plants – Bamboo, eucaplitas, neep, honey comb, herbs.
Fuel – Fuel wood, timber, fodder, coal, petroleum, natural gas, and biomass.
Productive use
Most commercial products are synthesized from natural products of biodiversity. The
product may be derived from plants, animals and by products.
Example : Silk, Wool, leather, tusk - from animals and
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Wood, cotton, oil, seed, crop – from plants.
Social Values
Social values of biodiversity counts for use of biodiversity for social aspect. The
consumptive and productive values of biodiversity are closely related to the social concern.
Many communities are finding that local bioversity can bring cash through ecotourism.
Many people value biodiversity as a part of livelihood through cultural and religious sentiments.
Holy plants – Banyan, peepal, lotus etc.
Holy animals – Cow, peacock, snake etc.
Ethical values
Ethical value of biodiversity is related to conservation of life. Plants and animals have equal right
to live and exist on our plant. No one has right to destroy other’s life. The ethical value tells that
any species may or may not be used buy its presence is must in ecology.
India’s rich heritage and culture tells us to worship animals. Plants, rivers and mountains. Some
communities have mission of preserving animal’s life.
Aesthetic values
Biodiversity is a beautiful and wonderful aspect of nature. Wild plants and animals are
source of beauty wonder, joy and recreational pleasure for many people. Wild life tourism
(ecotourism) is a good source of earning currency.
Example:
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Neem and mango leaves are used during festivals and fair aesthetics.
Ornamental plants, flowers are used for decoration.
Elephants, horses and camels are used for ceremonial purposes.
Option values
The potential use of biodiversity is proseutly not known to us, this future possible use is
termed as option value. Any specific species of biodiversity may be found very useful for any
particular purpose; if it is preserved and exists.
Example:
Rarely found medicinal plant may be used for medicinal purpose for any cronic disease.
Biodiversity of National Level
India occupies approximately 2.5% of the land area in the world and it contributes about
8% of the world’s biodiversity.
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India is an agricultural country and has about 6% of the world’s specie. The major species
include flowering plants, mammals, fish, birds and amphibians. India is the origin of values
domesticated animals and cultivated plant species. E.g. – rice, sugarcane, cotton, jute, mango,
turmeric, medicinal plants. India ranks 10th in the world and 4th in Asia in plant diversity.
India is a member of Convention in the Trade of Endangered Species (CITES) which is
intended to reduce the utilization of endangered plants and animals by controlling trade in their
products.
India as Mega Diversity Nation
India is one of the twelve centers of origin of cultivated plants. India has five heritage sites,
13 biosphere reserves and six wetlands. Also, India has 88 national parks and 490 sanctuaries.
Total number of plant species in India = 45000
Cultivated plants of species = 275
Number of endemic species (found in specific) areas = 4900 (18% of the world). All above
figures shows that India has a high biodiversity.
Threats of Biodiversity
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Habit loss
Poaching of wild life
Man – wild life conflicts
Destruction of coastal areas
Filling up of wetlands
Commercial exploitation
Habitat Loss
The loss of wild habitats, due to rapid human population growth contributes to the rapid
global destruction of biodiversity. Other important factors of loss of habitat are:
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Deforestation
Destruction of wetlands
Over grazing
Urban development
Building of dams
Mining
Land slides
Poor agricultural practices
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
Industrial wastes
Poaching of Wild Life
It’s for sport, making profit and for human consumption. Wild species are hunted for their
fur, tusks, meat, and thorns. Various animals and their purpose of producing article / use are
summarized here.
Sl. No.
Species
Use
1.
Elephant
Ivory, ashtray
2.
Alligators
Boots for urban needs
3.
Blubber
Lubricating oils
4.
Baleen
Combs and other articles
5.
Tiger
Skin and bones
6.
Rhinos
Horns
7.
Deer
Musk, perfume
Habit loss also occurs when man introduces species from one area into other disturbing the
balance of existing community. Species are lost due to destruction of natural ecosystem.
Man Wild Life Conflicts
Man is continuously interacting with different ecosystems for food, fuel, recreation, sports,
urban development, waste disposal etc. Every activity is responsible directly or indirectly
responsible for disturbing species.
Natural forests are being deforested for timber and single species trees like teak, sal. This
monoculture plantation creates imbalance ecosystem.
Natural size of forests are reducing because of human encroachment, therefore animals
often attacks on human society and creates violence.
Endangered Species of India
In an ecosystem, when number of species of a particular type is reduced to a critical level,
the species are said to be endangered.
Several plants and animal species in our country are found endangered. In India total 459
animals and plant species are endangered.
The endangered species are two types
1.
2.
Threatened species
Rare species.
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Factors Affecting Endangered Species
Various factors contribute to endangered species. Major factors are:

Pollution
All the waste by human and industries are disposed in environment. The wastes contains
various pollutants which ultimately enters into the food chain and food web and provides adverse
effect on lives on earth.
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Over-exploitation
Over exploitation of natural resources and poaching of wild animals also causes
endangered species.
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Climate Change
Certain species are disappearing because of climate change as they can not sustain change
in climatic condition.
Endemic Species
Species found in a particular region is called as endemic species. For example Endemic
species of plants – Two
Endemic species of animals – Seven
Number of factors contributes to endemic species, these are- habitat loss, pollution,
fragmentation.
Conservation of Biodiversity
Biodiversity is an important tool for sustaining development in any country. Multiple utility
of biodiversity in commercial, medical, genetic, aesthetic and ecological field makes it necessary
to preserve biodiversity. There is need to educate people to adopt environment friendly practices.
Advantages of Conservation of Biodiversity
1.
2.
3.
4.
5.
Biodiversity (ecotourism) is a good source of income.
Biodiversity provides various medicinal plants.
It provides life support system on earth.
Biodiversity maintain environmental balance on earth.
Various commercial aspects are related to biodiversity.
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Factors Affecting Biodiversity
1.
2.
3.
4.
5.
6.
7.
Over-exploitation of natural resources.
Degradation of habitat.
Discharge of industrial waste.
Global warming.
Urbanization.
Use of insecticides.
Construction of dam.
Approaches of Biodiversity Conservation
The two basic approaches of biodiversity conservation are:
1) In-situ conservation (on site) and
2) Ex-situ conservation (away from site)
In- situ conservation
It simply means conservation of species in its own habitat or natural ecosystem.
This strategy emphasizes protection of total ecosystem through a network of “protected
area”.
Protected Areas: an area of land and/or sea specially dedicated to the protection and
maintenance of biological diversity and managed through legal effective means.
There are different categories of protected areas which are managed with different
objectives. These include; Biosphere reserves, National parks, Wild Life Sanctuaries etc.
At present we have 11 major biosphere reserves, 80 National parks, 420 wildlife
sanctuaries in our country covering 4% of the geographic area.
The JIM CORBETT National Park was 1st national park established in India.
What is Difference among Biosphere reserves, National parks, Wild Life Sanctuaries ?
Examples of Biosphere reserves of India:
1. Nilgiri- 5,520 sq.km
2. Nanda Devi- 5,860.69 sq. km
3. Manas – 2837 sq. km
4. Gulf of Mannar – 10,500 sq. km
5. Great Nicobar – 885 sq. km
6. Panchmarhi – 4,926.28 Sq Km
Examples of some National Park in India
1. Kaziranga- Assam, Gir National Park- Gujarat, Periyar – Kerala, Sariska – Rajasthan
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Examples of some Wild Life Sanctuaries of India:
1. Ghana Bird sanctuaries
2. Hazaribagh sanctuaries
3. Abohar wild life sanctuaries
4. Jaldapara wild life sanctuaries
5. Mudamalai wild life sanctuaries
Ex- situ conservation
It is defined as “the conservation of component of biological diversity (Sample of genetic
diversity, particularly of endangered species) outside their natural habitats”.
It involves maintenance and breeding of endangered plant and animal species under
partially or wholly controlled conditions. E.g. Zoos, Botanical Gardens, Aquaria, Nurseries,
DNA bank, Seed bank, Gene bank etc.
There are more than 1500 Botanical gardens in the world containing more than 80,000
species.
There are more than 800 zoos around the world with about 3,000 species of mammals,
birds, reptiles and amphibians.
Steps of Conservation of Biodiversity
1.
2.
3.
4.
5.
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10.
11.
12.
Biodiversity inventories and assessments – population surveys and assessment.
Identifying and expanding protected areas.
Conserving biodiversity in seed banks and gene banks.
Controlling wild life trade.
Providing environmental education to the people.
Reviewing agricultural practices.
Controlling urbanization
Geographical information system for planning and monitoring
Restoration of biodiversity
Population control
Implementing environmental protection Act (EPA)
Involving more non government organizations (NGOs)
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Field Study
Study of Common Plants, Insects, Birds
a) Plants
1.
2.
3.
4.
5.
Identify list type of plant species.
Observe level of abundance of each type.
List characteristic features to identify species.
Role of plants in ecosystem.
How these can be protected.
b) Animals
1.
2.
3.
4.
5.
6.
Identify list type of animal species.
Observe level of abundance of each species.
List characteristic features.
Role of species in ecosystem.
Feeding and breeding behavior etc.
How these species can be protected.
Forest Ecosystem
a)
b)
c)
d)
e)
f)
g)
h)
i)
Classify forest type
Abiotic and biotic
Understand food chains and food pyramid
Structure of forest
Biomass distribution
Temperature, moisture of forest
Species diversity and animal species
Water cycle
Feeding pattern of animals
Grass land Ecosystem
a)
Seasonal changes of grass land
b)
Abandance of grass land species
c)
Bird watching
d)
Insect world
e)
Food chain of grass land
Desert
a)
Pattern and structure
b)
Birds and insects present
c)
Observe typical species
d)
Mammals observed
Aquatic Ecosystem
a)
Pattern and structure and nature of ecosystem
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b)
c)
d)
e)
f)
Observe vegetation, food chain and food pyramid
Ecosystem
Diversity
Effects of variation in season
Observe species, water cycle.
QUESTION BANK
1.
Define producers?
2.
Name the four ecosystems?
3.
What is ecological succession?
4.
What is food chain?
5.
Define ecology and ecosystem?
6.
Differentiate between food chain and food web?
7.
What are biomass
8.
What is biomagnifications?
9.
What is biogeochemical cycle?
10.
Define hydrological cycle.
11.
What is meant by tropic level?
12.
What is ecological pyramid?
13.
Define bio diversity.
14.
What is the significance of biodiversity system?
15.
Give the types of biodiversity.
16.
Define consumptive use of biodiversity.
17.
What are endemic species?
18.
Give factors affecting endangered species.
19.
List the factors affecting biodiversity.
20.
What is meant by in-situ conservation?
21.
What is meant by Ex-situ conservation?
22.
Enumerate the human activities that destroy the biodiversity.
23.
Explain the Carbon cycle.
24.
Justify India as mega diversity nation.
25.
List the practical issues involved with disrupting the food chain of the following
ecosystem. a. Forest ecosystem b. Grassland ecosystem. C. Aquatic system.
26.
Explain the various threats to and measures recommended for conservation of biodiversity.
27.
Explain Energy flow in eco system.
28.
Explain the features of aquatic ecosystem.
29.
Explain the role of producers, consumers and decomposers in an ecosystem.
30.
What are the different types of eco system and explain them with an example?
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