Unit II- Ecosystem and Biodiversity(1).ppt.pdf

Ecosystem and Biodiversity
Dr. P. Srinivasan
UNIT-II

Ecosystems:
Concept and components of an ecosystem -structural and functional features –
Functional attributes (Food chain and Food web only).
Biodiversity:
Introduction – Classification – Bio-geographical classification of India- Value
of biodiversity – Threats and Conservation of biodiversity - case studies.

Ecosystems
A self-regulating group of biotic communities of species interacting with one another
and with their non-living environment exchanging energy and matter.
Study of the ecosystems is often known as - Ecology
Ecosystems consists of interacting plants, animals and microorganisms as well as
non-living components (soil, water, O2
etc,.)
Life on the earth is sustained by the flow of energy from the sun and cycling of
nutrients through the ecosystems

Structural and Functional Components of Ecosystems
Each ecosystem comprises of two basic components
1. Abiotic Components 2. Biotic components

Abiotic Components or Non-living components
These include the non-living, physico-chemical factors such as air, water, soil, elements
and compounds of the environment. It is broadly classified as
1. Climatic factors- which include the climatic regime and physical factors of the
environment like sunlight, humidity, temperature, wind, rainfall,
water, etc.,
2. Edapic factors - which are related to the structure and composition of soil such as
minerals, soil organisms, organic substances, etc.,
Biotic Components or Living components
It comprises the living part of the environment (like plants & animals) which is made up
of many different inter-dependent organisms. Biotic components are distinguished into
autotrophs, heterotrophs, saprotrophs.

I. Autotrophs or producers – which can synthesize their food
themselves from compounds that are obtained from their environment.
Photoautotrophs – mainly green plants uses light as energy source
and synthesize their food themselves through the process of
photosynthesis.

Chemo-autotrophs: chemo-autotrophs are microorganisms which can
produce food to some extent through oxidation of certain chemicals in
the absence of sunlight.
Ex. Chemoautotropic sulphur bacteria make use of the heat generated
by the decay of radioactive elements (present in the earth’s core and
released in ocean’s depths). They use this heat to convert dissolved H2
S
and CO2
into organic food sources.

II. Heterotrophs or Consumers:
They mainly depend on the producers for their food.
They are further classified as
1.Herbivores or primary consumers
2.Carnivores or Meat eaters
3.Omnivores
1.Herbivores or primary consumers:
They directly feed on producers. Eg. insects, rabbit.
2.Carnivores or Meat eaters: They feed on other animals for their food
Primary carnivores or secondary consumers:
They take food from herbivorous animals. Eg. Fox
Secondary carnivores or tertiary consumers:
They take food from primary carnivores. Eg.Wolf

Tertiary carnivores or quaternary consumers:
They take food from other carnivores. Eg.lion.
3.Omnivores: They take food from both plants and animals.
Eg. Birds, humans, rat
4.Detritivores: They feed on dead organisms.
Eg. beetles, vultures, ants, termites
III. Saprotrophs or Decomposers
They derive their nutrition by breaking down the complex
organic molecules to simple organic compounds and ultimately
into inorganic nutrients. Eg. Bacteria, fungi
In few ecosystem, biotic structure prevails eg. Forest, while in others
decomposers predominates
Eg. Deep ocean

Functions of Ecosystems
Each ecosystem functions systematically under natural conditions.
It receives energy from sun and transfers it through various biotic and abiotic
components.
All life on earth depends upon this flow of energy. Besides energy, various nutrients
and water also exchanged within the biotic and abiotic community.
Tropic levels (or) Feeding levels
The various steps through which food energy passes in an ecosystem is
called as Tropic level.
1st
Trophic Level: Producer, 2nd
Trophic Level: Primary Consumer
3rd
Trophic Level: Secondary Consumer 4th
Trophic Level: Tertiary Consumer
The transfer of energy and nutrient occurs in the following ways
1. Food Chain
2. Food Web

1. Food Chain : Sequence of eating and being eaten in an ecosystem
✔ All organisms, living or dead, are potential food for some other organisms.
✔Food chains in ecosystems are rarely found to function as isolated linear sequences.
They are found to be interconnected and usually form a complex network with several
linkages known as food web.

2. Food Web : Interlocking pattern of various food chains of an ecosystem
Food web is a network of food chains where different organisms are connected at
different tropic levels, so that there are a number of options of eating and being eaten at
each tropic level.

Nature has evolved food webs in ecosystems instead of simple linear food chains
Because food webs give greater stability to the ecosystem.
In linear food chain, if one species becomes
extinct then the species in subsequent
tropic levels are also affected.
In food web there are a number of options
available at each tropic level. So if one species
Is affected, it does not affect other tropic levels.

Significance of food chains and food webs
1. Energy flow and nutrient recycling takes place through them
2. Regulates population size of organisms and maintain ecological balance
3. Food chains show a unique property of biological magnification of some
chemicals.
Non-biodegradable chemicals are not decomposed by microorganisms
and they keep on passing from one tropic level to another. At each successive
tropic level, concentration of chemical increasing. This phenomenon is known
as biological magnification

Case Study
Bio-magnification of DDT
Bio-magnification happens when toxic chemicals, like DDT, whose remains in the
environment are consumed indirectly by organisms through food. When an organism in
the higher food chain consumes the lower organism containing such chemicals, the
chemicals can get accumulated in the higher organism. In other words, it travels through
the food chain harming every single stratum. The concentration of these toxins or
chemicals increases through the trophic levels of the food chain.
Moreover, because of its non-biodegradable character, it can remain in soil or water for
many years leading to a very dangerous and concerning process – bio-magnification.

Unit II- Ecosystem and Biodiversity(1).ppt.pdf

BIODIVERSITY
Introduction
Biodiversity is a term used to describe the enormous
variety of life on Earth.
The term Biodiversity is coined by Walter Rosen- 1985.
About 50 million species of plants, animals and microbes
are existing in the world.
Among this only 2 million are identified so far.
*

Biodiversity is the biological variety
and variability of life on Earth.
Biodiversity is a measure
of variation at the genetic,
species, and ecosystem level.
Terrestrial biodiversity is usually greater near the equator, which is the result of the warm
climate and high primary productivity.
Biodiversity is not distributed evenly on Earth, and is richer in the tropics.
*

These tropical forest ecosystems cover less than ten percent of earth's surface, and
contain about ninety percent of the world's species.
Marine biodiversity is usually higher along coasts in the Western Pacific, where sea
surface temperature is highest, and in the mid-latitudinal band in all oceans.
There are latitudinal gradients in species diversity. Biodiversity generally tends to
cluster in hotspots, and has been increasing through time, but will be likely to slow
in the future as a primary result of deforestation.
It encompasses the evolutionary, ecological, and cultural processes that sustain life.
*

Definition:
Biodiversity refers to the variety and variability among all groups of living organism and the
ecosystem complexes in which they occur.
The International Day for Biological Diversity is marked on May 22.
The theme of the day this year has been finalized as, “We’re part of the solution For Nature."
The idea behind choosing this as the theme is to draw people’s attention towards the fact that
biodiversity continues to be the answer for a significant number of sustainable development
challenges.
*

Levels/Classification of Biodiversity
Biodiversity is wide-ranging and is normally divided into three types or levels
Genetic Diversity
Species Diversity
Ecological Diversity
❖ Genetic Diversity:
It is the basic source of biodiversity
All species on Earth are somewhat related through genetic connections. And the more
closer a species is related to another, the more genetic information the two species will
share. These species will also look more similar.
*

The closest relations of an organism are members of its own species. Members of a species
share genes.
Genes are the bits of biochemical information that partly determine how an organism looks,
behaves, and lives.
Virtually every species in an environment has a similar and closely related species in a
neighboring environment.
The genetic structure and subdivision of this crop remain unclear at both global and local
scales.
Using 84 nuclear simple sequence repeat markers, we genotyped a panel of 153 global rice
cultivars covering all previously recognized groups and 826 cultivars representing the
diversity of Chinese rice germplasm.
*

On the basis of model-based grouping, neighbour-joining tree and principal coordinate
analysis, we confirmed the widely accepted five major groups of rice cultivars (indica, aus,
aromatic, temperate japonica and tropical japonica), and demonstrated that rayada rice was
unique in genealogy and should be treated as a new (the sixth) major group of rice
germplasm.
Additionally, every species has other, more distantly related species. These two species share
a more general set of traits.
The Oryza sativa family
*

*
Species Diversity:
❖ Species diversity refers to the
variety of different types of
species found in a particular area.
❖ It represents broadly the species
richness and their abundance in a community.
There are two popular indices of measuring species diversity.
1.Shannon-Wiener index
2.Simpson index

Ecological Diversity
Ecological diversity (also called ecosystem diversity) is usually considered to be a type of
biodiversity and deals with the variations within or across ecosystems.
It can encompass factors such as
the number of ecological niches,
the trophic levels, and/or the
physical complexity of the
ecosystem(s),in addition to the richness and diversity of the species that inhabit it.
*

It can be used to compare similar ecosystem types, like a rainforest in Brazil to a rainforest in
Sumatra, or across ecosystem types, like a rainforest vs a desert, or even across different
systems in the same area, like a suburban neighborhood and the surrounding forest.
The ecosystem diversity is of great value that must be kept intact. This diversity has developed
over millions of years of evolution.
If we destroy this diversity, it would disrupt the ecological balance.
we cannot even replace the diversity of one ecosystem by that of another.
*

Bio-Geographical Classification of India
India is one of the 12th Mega diverse regions of world. (Mexico, Columbia, Madagaskar,
Ecuador, Cameroon, Peru, Brazil, Jaira, China, Malaysia, Indonesia and India).
India can be conveniently divided into ten major regions based on geography, climate and
pattern of vegetation seen and the communities of mammals, birds, reptiles,
amphibians, insects and other invertebrates that live in them.
Each of these regions contains a variety of ecosystems such as forests, grasslands,
lakes, rivers, wetlands, mountains and hills which have specific plants and animal
species.
*

Bio-geographic classification of India describing 10 bio-geographic zones in India
are further divided into 25 secondary units called biogeographic provinces giving weight
to particular communities separated by dispersal barriers or gradual change in
environmental factors.
The classification was done using various factors such as altitude, moisture, topography,
rainfall, etc.
Biogeographic zones were used as a basis for planning wildlife protected areas in India.
The 10 bio-geographic zones which are distinguished clearly in India and each
harbour its own assemblage of animal and plant communities.
*

There are ten biogeographic zones in India
1.Trans Himalayan zone.
2.Desert zone.
3.North east zone.
4.Islands.
5.Himalayan zone
6.Western ghat zone.
7.Gangetic plain zone.
8.Deccan plateau zone.
9.Semiarid zone.
10.Coastal zone.
*

Trans- Himalayan Region
The Trans Himalayan regions of the states of Jammu
and Kashmir and Himachal Pradesh are a moonscape
land – an arid high altitude desert unlike any other
part of the Indian subcontinent.
The stark landscape is a panorama of high
snowcapped peaks and bare multihued hills sculpted
by the forces of nature.
The high dusty valleys strewn with rock have
altitudes ranging from 2,500m to 4,500m.
Important flora and fauna: Pine, Deodar, Wild sheep,
Yak, Leopard Marmot, Blacked necked crane.
*

Desert Zone
This includes Rajasthan, Haryana, Gujrat and Kachha.
The climate is dry. The common animals which are found
here are Donkey, Deer, Cheetal, Neelgai. Different types of
snakes and lizards are also very common.
The Indian part of the Thar Desert occupies 170,000 km2
(66,000 sq mi). The climate is characterised by very hot
and dry summer and cold winter. Rainfall is less than 70
cm.Babul, Kikar, and wild date palm grow in areas of
moderate rainfall.
*

North-East Zone
North-east India is one of the poorest regions in the country.
It has several species of orchids, bamboos, ferns and other plants. Here the wild relatives of
cultivated plants such as banana, mango, citrus and pepper can be grown.
The area of North East India covers Bramaputra Valley- 65200 Sq.Km, North-Eastern Hills-
106200 Sq.Km.
*

Islands
The two groups of islands, i.e., the Arabian Sea islands and Bay Islands differ
significantly in origin and physical characteristics.
The Arabian Sea Islands (Laccadive, Minicoy, etc.) are the foundered remnants of the
old land mass and subsequent coral formations.
On the other hand, the Bay Islands lay only about 220 km. Away from the nearest point
on the main land mass and extend about 590 km.
With a maximum width of 58 km the island forests of Lakshadweep in the Arabian Sea
have some of the best-preserved evergreen forests of India.
Important flora and fauna: Bahera, Harar, Jack fruit, Cardamom, Coconut, Dolphin,
Alligator, Molluscs.
*

Himalayan zone
Himalayas was originally part of the Indo-Burma Biodiversity Hotspot.
In 2004, a hotspot reappraisal classified the region as part of two hotspots:
Indo-Burma and the newly distinguished Himalaya.
The Eastern Himalaya includes Bhutan, southern, central and eastern Nepal, and
northeastern India, and comprises 11 Key Biodiversity Areas (occupying 750,000
hectares).
It covers North-West Himalayas- 6900 Sq.Km, West himalayas-720000 Sq.Km,
Central Himalayas- 123000 Sq.Km.
Pine
Cork Tree
Wild bear
*

Western ghat zone
It supports the life of 7,402 species of flowering plants,
1814 species of non-flowering plants, 139 mammal species,
508 bird species, 179 amphibian species, 6000 insects species
and 290 freshwater fish species.
And many are still to be discovered. Western Ghats is a mountain range that runs through
the states of Gujarat, Maharashtra, Goa, Karnataka, Kerala and Tamil Nadu.
Total area of Malabar coast-59700 Sq.Km, Western Ghat Mountains -99300 Sq.Km.
Important flora and fauna- Sheesham, Peepal ...
*

Gangetic Plain Zone
The thickness in the alluvial sediments varies considerably with its maximum in the Ganga
plains.In the North is the Gangetic plain extending up to the Himalayan foothills.
This is the largest unit of the Great Plain of India. Ganga is the main river after whose name
this plain is named.
The aggradational Great Plains cover about 72.4mha area with the Ganga and the Brahmaputra
forming the main drainage axes in the major portion.
Upper Genetic plain covers 206400 Sq.Km.
Lower Genetic plain covers 153000 Sq.Km.
*

Deccan Plateau Zone
This is the largest unit of the Peninsular Plateau of India.
The highlands of the plateau are covered with different types of forests, which provide a large
variety of forest products.the Deccan plateau includes the region lying south of the Satpura
range.
It extends up to the southern tip of peninsular India.
Anaimudi is the highest peak of this region.
The Deccan plateau is surrounded by the western
and the Eastern Ghats.
These ghats meet each other at the Nilgiri hills.
The Western Ghats includes the Sahyadri, Nilgiris, Anamalai,
and cardamom hills.
Total area of Deccan south- 378000, Central plateau-341000, Eastern plateau-198000
Important flora and fauna- Tuna, Pine, Castor,Sloth bear, Tigar..
*

Semi Aired Zone
Adjoining the desert are the semi-arid areas, a transitional zone between the desert and the
denser forests of the Western Ghats.
The natural vegetation is thorn forest. This region is characterized by discontinuous vegetation
cover with open areas of bare soil and soil-water deficit throughout the year.
Thorny shrubs, grasses and some bamboos are present in some regions.
Important flora and fauna- Acacia, Date palm, Gir Lion..
*

Coastal zone
The west coast is narrow except around the Gulf of Cambay and the Gulf of Kutch.
In the extreme south, however, it is somewhat wider along the South Sahyadri.
The backwaters are the characteristic features of this coast.
The east coast plains, in contrast are broader due to depositional activities of the east-flowing
rivers owing to the change in their base levels.
Total area of west coast and East coast is 6500 Sq.Km
Important flora and fauna- Coconut, Banana, Dolphin,Turtle....
*

Values of biodiversity
Introduction:
Biodiversity is the most precious gift of nature the mankind is blessed with. The
uniqueness of our planet Earth is due to the presence of life manifested through the
diversity in flora and fauna.
As all the organisms in an ecosystem are interlinked and interdependent, the value
of biodiversity in the life of all the organisms including humans is enormous. Besides its
ecological and environmental value, biodiversity has significant socio-economic values
as well.na.
Biodiversity or biological diversity simply means the variety and variability among
living organisms and the ecological complexes in which they occur. Such variety refers
to the variety at the species, genetic and ecosystem level.
*

*
Value of Biodiversity:
The biodiversity value has been classified by McNeely et al in 1990 as follows;
(i) Consumptive use value
(ii) Productive use value
(iii) Social value
(iv) Ethical value
(v) Aesthetic value
(vi) Option value
(vii) Ecosystem service value

(i) Consumptive use Value:
These are direct use values where the biodiversity product can be harvested
and consumed directly
e.g. food, fodder, timber, fuel wood, etc.
Humans use at least 40,000 species of plants and animals on a daily basis. Many
people around the world still depend on wild species for most of their needs like food,
shelter and clothing. The tribal people are completely dependent on the forests for their
daily needs.
Similarly, fishermen in the coastal areas are dependent on the marine resources.
The wood derived from the forests has been used from the birth of civilization as fuel.
*

*
Common modern drugs obtains rom plants

(ii) Productive Use Value:
This is assigned to products that are commercially harvested and marketed.
It may include lumber or wild gene resources that can be traded for use by
scientists for introducing desirable traits in the crops and domesticated animals. These
may include the animal products like tusks of elephants, musk from musk deer, silk
rom silk-worm, wool from sheep, fur of many animals, lac from lac insects etc. all of
which are traded in the market.
*

(iii) Social Value:
These are the values associated with the social life, customs, religion and
psycho-spiritual aspects of the people.
While traditional societies had valued and preserved their biodiversity and its
resources, modern man has depleted it up to the extent leading to irrecoverable
loss due to extinction of several species.
Ecosystem people’ value biodiversity as a part of their livelihood , as well as
through cultural and religious sentiments.
*

(iv) Ethical Value:
Ethical values of biodiversity are based on the importance of protecting all form of life. It is
known as existence value. It involves ethical issues like “all life must be preserved”. It is based on
the concept of “Live and Let Live”. If we want our human race to survive, then we must protect all
biodiversity, because biodiversity is valuable.
Most religious and secular creeds believe that all form of life have the right to exist on Earth.
Man is only a small part of the Earth’s great family of species; plants and animals have an equal
right to live and exist on our planet. There are several cultural, moral and ethical values,
associated with the holiness of all forms of life.
Morality and ethics teach us to preserve all forms of life and not to harm any organism
unnecessarily. Some people take pleasure in the hunting of animals. People also sometimes
degrade and pollute the environment by their unethical actions.
*

(v) Aesthetic Value:
The beauty of our planet is because of biodiversity, which otherwise would have
resembled other barren planets dotted around the universe. Biological diversity adds to
the quality of life and provides some of the most beautiful aspects of our existence.
Biodiversity is responsible for the beauty of a landscape. Humans are also attracted
towards the biologically rich regions and nobody likes to live or visit a barren place.
People go to far off places to enjoy the natural surroundings and wildlife.
This type of tourism is referred to as eco-tourism, which has now become a major
source of income in many countries. Eco-tourism includes visiting wildlife sanctuaries,
national parks, coral reefs, exotic islands, safaris and trekking in the mountainous and
forested areas. In some countries like Nepal, Bhutan, Kenya, Rwanda, eco-tourism has
now become the major source of foreign currency income.
*

(vi) Optional Value:
This refers to the value of biodiversity that is yet unknown, but needs to be explored
for future possibilities and use. Scientists have discovered and named about 1.75
million species, which is of utmost importance. We should preserve all the world’s
biodiversity that can be used by the future generations.
A species potential to provide an economic benefit to human society at some point
in the future is its option value. As the needs of the society change , so must the
methods of satisfying those needs. The option value of species could be only recently
utilized by human beings
*

Health agencies and pharmaceutical companies are making a major effort to
collect and screen species for compounds that have the ability to fight cancer.
In some cases well known species have been found to have exactly those
properties needed to deal with a significant human problem.
*

(vii) Ecosystem service value:
The suite of benefits that people receive from the environment.
Include:
Primary production
Flood control
Climate regulation
Waste treatment
Water purification, etc...
*

*
Current state of ecosystem services:
Capacity of ecosystems to provide services is decreasing.
Pressure from deforestation
habitat modification
fragmentation, intensification of land use
invasive species
pollution

*
Role of plants in ecosystem services
FOOD WOOD
FIBRE MEDICINE

Role of plants in ecosystem services:
Water purification Carbon sequestration
Flood prevention Waste treatment

Global biodiversity hotspots:
A biodiversity hotspot is a
region with a high level
of endemic species.
• Hotspots were first named in 1988 by Dr. Sabina V.
• To qualify as a hotspot, an area must hold at least 1500 endemic species – Brazil's
Atlantic Forest is containing roughly 20,000 plant species &1,350 vertebrates etc
• All 34 hotspots contain 50% plant species, 42% terrestrial vertebrates.
• Hotspots cover 15.7% of the land surface.
• Intact hotspot habitat equals 2.5 of the total land surface.
*

Biodiversity Status in India:
India is one of the 12 mega-biodiversity countries of the
world.
It is estimated that 70%of the world’s total flowering plants occur in India
Indian gets 10th place in the world and 4th in Asia among
these 12 mega-diverse countries
India has 10 biogeographic zones. They are Trans-Himalaya, Himalaya, Desert,
Semi-arid, Western ghats, Deccan peninsula, Gangetic plain, Coasts, North-East, Islands
It is among top 10-15 nations of the world for its great
diversity of plant life, especially flowering plants
India is a source of traditional crop varieties ranking first amongest the 12 regions of
diversty of crop plants and seventh in the contribution of agricultural species
*

*
India is the origin of 166 species of crop plants and
320 species of wild relatives of cultivated crops
India’s marine biodiversty is als rich, supporting the most productive ecosystems such as
mangroves, coral reefs and estuaries
In India, among plant kingdom angiosperms tops the list(17,500 species) while
gymnosperms are the least, comprising only of 64 species
In India, among animal kingdom, arthropoda tops the list(68,389) while Protochordata are
the list with only 119 species
The endemics are concentarted mainly in western ghats, NE Himalayas, NW Himalayas and
Andaman & Nicobar islands. About 33% of the flowering plants present are endemic
About 53%fresh water fishes are endemic
About 60%of amphibians are endemic mostly in western ghats
About 36%reptiles are endemic
About 10%mammals are endemic

*
SPECIES DIVERSITY AND ENDEMISM HIMALAYAS :
Taxonomic group Species Endemic species Endemism(%)
Plants 10000 3160 31.6
Mammals 300 12 4
Birds 977 15 1.5
Reptiles 176 48 27.3
Amphibians 105 42 40
Freshwater
Fishes
269 33 12.3

SPECIES DIVERSITY AND ENDEMISM IN WESTERN GHATS :
Taxonomic group Species Endemic species Endemism(%)
Plants 5916 3049 51.5
Mammals 140 18 12.9
Birds 458 35 7.6
Reptiles 267 174 65.2
Amphibians 178 130 73
Freshwater Fishes 191 139 72.8

Reginal or local Biodiversity:
Biodiversity at regional level is better understood by categorizing species richness into
four types, based upon their spatial distribution.
Point richness: the number of species that can be found at single point in a given space.
Alpha richness: the number of species found in a small homogeneous area.
Beta richness: the rate of change in species composition across different habitats.
Gamma richness: the rate of change cross large landscape gradients
*

HOTSPOTS OF BIODIVERSITY
Biodiversity refers to the variety and variability among all groups of living organisms and
ecosystem complexes in which they occur.
Areas which exhibit high species richness as well as high species endemism are termed
as HOT SPOTS OF BIODIVERSITY.
To qualify as a hotspot, a region
must meet two strict criteria:
it must contain at least 1,500
species of vascular plants
(> 0.5 percent of the world's total)
as endemics,and it has to have
lost at least 70 percent of its
original habitat.
*

Important hot spots
1.western Ghats and Sri Lanka
2.Himalaya
3.Mediterranean basin 4.Indo-Burma
5.Horn of Africa
6.Madagacsar and Indian ocean islands
7.Sundaland
8.Forests of Australia
9.Caucasus
10.Mesoamerica
*

WESTERN GHATS AND SRI LANKA
Western Ghats of southwestern
and southwestern Srilanka are similar
in geology, climate and evolutionary history.
The western Ghats, known locally as
the Sahyadri hills run parallel to India's
western coast, about 30 to 50 Km inland.
They cover an area about 1,60,000 Sq Km
and stretch for 1,600 Km from Gujarat
to south tip.
*

HIMALAYAN
Includes the entire Indian Himalayan
region (and that falling in Pakistan,
Tibet, Nepal, Bhutan, China and
Myanmar).
The Himalaya Hotspot is home to the
world's highest mountains.
The hotspot is home to important
Populations of numerous large
birds and mammals, including vultures,
tigers, elephants, rhinos and wild
water buffalo.
*

*
Rafflesia arnoldii
red-knobbed hornbill
Sunda Clouded Leopard

Endangered Species :
A species of plant or animal that is in immediate danger of becoming extinct and needs
protection to survive.
Concept:
The endangered species are those
living organisms which are almost
on the critical level.
Thousands of species of plants and animals
are endangered and the number increases
each year.
Kokkare Bellure, Karnataka:
Pelican species –
They need to be preserved because droppings
of these fish eating birds are rich in nitrates
which is a good fertilizer

ENDEMIC SPECIES:
Concept :
The concept of Endemism was first given by CANDOLLE.
When a species is found only in a particular geographical region because of its isolation, soil
and climatic conditions, it is said to be endemic
The Indian Desert:
Mangrove Trees – Mangrove roots
provide support to unstable soils
and withstand currents and storms.

Threats to biodiversity
Habitat destruction - Important to protect habitat in order to protect biodiversity within it.
Huge pressure from the World’s rapidly increasing population.
Global climate change - Change in a biotic elements of ecosystems leading to biotic
change.
Habitat fragmentation - From human activity. Reduces ability of habitat to support
species.
Pollution - Introduction of pollutants such as nutrient overloading with nitrate fertilizer
as well as more immediately harmful chemicals.
Over-exploitation - This includes the illegal wildlife trade as well as overfishing, logging
of tropical hardwoods etc.
Alien species - Introduced by humans to regions where there are no natural predators.
Disease - Reduction in habitat causing high population densities,
encourages spread of diseases.
*

Loss of Habitat:
Destruction and loss of natural
habitat is single largest cause of biodiversity loss.
Habitat loss can be described when an animal loses their home. Every animal in the animal kingdom
has a niche, a their in their animal community and without their habitat they no longer have a niche.
Reasons of habitat loss by humans:
~ agriculture, farming
~ harvesting natural resources for personal use
~ for industrial and urbanization development
Habitat destruction is currently ranked as the primary
causes of species extinction world wide…!!!
*

HABITAT FRAGMENTATION:
Natural disturbances or changes in land use lead to the fragmentation of forests. such
habitat changes have a significant impact on biodiversity, as small fragments of habitat
can only support small populations that tend to be more vulnerable to extinction.
It results in reduction of a large, continuous area into two or more fragmented
reduced area . The fragments have greater amount of edge area the original habitat
and also the core of the fragmented habitat is nearer the edge.
*

Poaching:
It is the hunting and harvesting
taking of wild plants or animals,
such as through hunting,
harvesting, fishing, or trapping
*

Why Poaching is done???
Poaching is done for large profits gained by the
illegal sale or trade of animal parts, meat and pelts.
Exists because there is a demand for these
products, caused by a lack of education or disregard for the law
amongst the buyers
Many cultures believe that certain animal parts
have medicinal value.
*

Poaching is not limited to animals
its also for plants too…………!
Three of the most often poached species in the park
are galax, black cohosh, and ginseng.
*

How does poaching affect the
environment?
Poaching or illegal hunting causes animals endangered of being extinct. If
more animals becomes extinct there's a disruption in the food chain, and that
will
cause major problems in our ecosystem, resulting
eventually in new adaptations of animals, and or species beyond human
control.
Poaching results in animals being hunted too soon for
them to have time to reproduce and repopulate.
*

Man- wild conflicts
Increase in man wildlife conflict is due to resource limitation like :
1.Space ,2. Food , 3. Shelter
It is also due to Increasing population of human beings , Loss of
forest, decrease in quality of forest and development activities.
In India, wild elephants probably kill far more people than tiger, leopard or lion.
Damage to agricultural crops and property, killing of livestock and human beings are some of the
worst forms of man-animal conflict.
Farmers sometimes poison and shoot wild animals as they damage their crops, but this can be
prevented by taking certain measures.
*

Ways to reduce the conflicts
Governments is working on
improvement of habitat to augment
food and water availability and to
Reduce movement of animals from the
forests to the habitations.
Training forest staff and police
to tackle these situations and creating
awareness among the people about the
Do’s and Don’ts to minimize conflicts .
construction of boundary walls
and solar fences around the
sensitive areas to prevent the wild
animal attacks.
Some devices of Information Technology, viz., radio collars with
Very High Frequency, Global Positioning System and Satellite uplink facilities can be used
the movements of wild animals .
*

Endangered Species:
The International Union of Conservation of Nature and Natural Resources (IUCN)
publishes the Red Data Book which includes the list of endangered species of plants and
animals. The red data symbolizes the warning signal for those species which are
endangered and if not protected are likely to become extinct in near future.
*
Persian leopards
brown bears
golden eagles
bison

Conservation of Biodiversity:
The convention on Biological Diversity held in June, 1992 stressed the need of the
conservation of Biodiversity for sustainable development and perpetuation of human beings
on earth.
Conservation is defined as “ the management of human use of the biosphere so that it may
yield the greatest sustainable benefit to the present generation while maintain in gits
potential to meet the needs and aspirations of the future generations”.
The two basic approaches to wildlife conservation in protected habitats are:
1) In-situ conservation and
2) Ex-situ conservation.
*

In-situ conservation:
It means conservation of species in its natural ecosystem or even in manmade
ecosystems
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 1stnational park established in India.
*

Examples of Biosphere reserves of India:
It conserve some representative ecosystems as a whole long-term in situ
conservation. Nilgiri-5,520 sq.km
Nanda Devi - 5,860.69 sq. km
Manas – 2837 sq. km
Gulf of Mannar – 10,500 sq. km
Great Nicobar – 885 sq. km
Panchmarhi – 4,926.28 sq Km
Examples of some National park in India:
It is an area dedicated for the conservation of wildlife along with its environment.
Kaziranga - Assam
GirNational Park - Gujarat
Periyar – Kerala
Sariska – Rajasthan

Wild Life Sanctuaries of India:
It is also protected areas where killing, hunting, shooting or capturing of
wildlife is prohibited except under control of highest authority.
Examples:
Ghana Bird sanctuaries
Hazaribagh sanctuaries
Aboharwild life sanctuaries
Jaldaparawild life sanctuaries
Mudamalaiwild life sanctuaries
*

Ex-situ conservation
It is defined “ 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.
*

In India, we have many gene bank. The important ones are:
National Bureau of Plant genetic Resources (NBPGR),New Delhi:
Agricultural and horticultural crops and their wild varieties are preserved by
cryo-preservation of seeds (at -196º C in Liquid Nitrogen), pollen etc.
National Facility for Plant Tissue Culture Repository (NFPTCR) at NBPGR Campus New
Delhi:
It has been set up for the development of a facility of conservation of varieties of crop
plants/ trees by tissue culture.
Natioanl Bureau of Animal Genetic Resources (NBAGR) at located at Karna, Haryana:
It preserves the semen of domesticated bovine animals.
Institute of Forest Genetics and Tree Breeding (IFGTB):
Located Forest Research Institute, Coimbatore, Tamilnadu. It mainly aims to
identify and evolve different species used in social forestry and afforestation.
*

Unit II- Ecosystem and Biodiversity(1).ppt.pdf

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