UNIT-II

Ecosystem and Biodiversity

Dr.A.Geetha

Associate Professor

Department of Chemistry Kongu Engineering College Perundurai, Erode-638 060

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

Dr.A.

• 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

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• Climatic factors- which include the climatic regime and physical factors of the environment like sunlight, humidity, temperature, wind, rainfall, water, etc.,

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• Edapic factors - which are related to the structure and composition of soil such as minerals, soil organisms, organic substances, etc.,

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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 H₂S 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

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1. Herbivores or primary consumers:

They directly feed on producers. Eg. insects, rabbit.

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2. Carnivores or Meat eaters: They feed on other animals for their food

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• Primary carnivores or secondary consumers:

They take food from herbivorous animals. Eg. Fox

• Secondary carnivores or tertiary consumers:

They take food from primary carn^ivores

Tertiary carnivores or quaternary consumers:

They take food from other carnivores. Eg.lion.

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3. Omnivores: They take food from both plants and animals. Eg. Birds, humans, rat

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• Detritivores: They feed on dead organisms. Eg. beetles, vultures, ants, termites

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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

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Functions of Ecosystems

• Each ecosystem functions systematically under natural conditions.

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• 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.

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• Tropic levels (or) Feeding levels
• The various steps through which food energy passes in an ecosystem is called as Tropic level.

1^st Trophic Level: Producer,

3^rd Trophic Level: Secondary Consumer

2^nd Trophic Level: Primary Consumer

4^th 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.

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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.

BIODIVERSITY

• 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.

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• Biodiversity is a measure of variation at the genetic,

species, and ecosystem level.

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• 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.

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• 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.

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• 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.

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• It encompasses the evolutionary, ecological, and cultural processes that sustain life.

• 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

• 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 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 (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

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physical complexity of the

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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.

• If we destroy this diversity, it would disrupt the ecological balance.
• we cannot even replace the diversity of one ecosystem by that of another.

• 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.

• 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.

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.

• 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.

• 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 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.

• 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.

• 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.

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Pine

Cork Tree Wild bear

• 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 ...

• 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.

• 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.

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• 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..

• 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..

• 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:

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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;

1. Consumptive use value

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• Productive use value

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• Social value

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• Ethical value

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• Aesthetic value

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• Option value

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• 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

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(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.

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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.

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Include:

Primary production Flood control Climate regulation Waste treatment

Water purification, etc...

Ecosystem services

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Current state of ecosystem services:

• Capacity of ecosystems to provide services is decreasing.

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• Pressure from deforestation
• habitat modification

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• fragmentation, intensification of land use

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• invasive species

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• 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:

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A biodiversity hotspot is a region with a high level

of endemic species.

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• 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:

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India is one of the 12 mega-biodiversity countries of the

world.

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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

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• 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

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320 species of wild relatives of cultivated crops

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• 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 :

SPECIES DIVERSITY AND ENDEMISM IN WESTERN GHATS :

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.

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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

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• Western Ghats of southwestern

and southwestern Srilanka are similar

in geology, climate and evolutionary history.

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• The western Ghats, known locally as the Sahyadri hills run parallel to India's western coast, about 30 to 50 Km inland.

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• 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).

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• The Himalaya Hotspot is home to the world's highest mountains.

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• 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.

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Reasons of habitat loss by humans:

• agriculture, farming
• harvesting natural resources for personal use
• for industrial and urbanization development

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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.

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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 .

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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.

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Persian leopards

brown bears

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.

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• 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”.

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• The two basic approaches to wildlife conservation in protected habitats are:
• In-situ conservation and
• 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

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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

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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.

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Examples:

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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”

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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:

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• 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.

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• 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.