2nd lecture on biodiversity

8/3/2019 2nd Lecture on Biodiversity

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Maintain Natural System

It provides the natural units through which materials and energy flow, giving

ecosystems and biomes their functional properties

Very different kinds of biodiversity are needed to provide resilience whenunusual surprises occur – volcanic eruptions, meteor impacts, major fires,

disease outbreaks, etc.

Direct economic benefits

Providing selected crops or animals Provide Wood, dyes and Fibers

Providing new pharmaceutical compounds

Why is biodiversity important?



Indirect economic benefits

Pollination

Decomposition of organic material

Nutrient transfers in soil

Regulate Climate

Ecosystem services

Scientific value

Providing models for many devices used by humans (Velcro to Jet engines)

Recreational and Aesthetic Value

Ecotourism- tourist attraction (Tourist visit a place in order to observe wildspecies or unique ecological sites)

Sit in a forest and listen to the birds, Watch a spider weave its complex web,

observe a fish feeding. They all activities are magnificent and fascinating

The Tulsi has been placed at our doorsteps for centuries

Hiking

Hunting

Fishing

Photography

Options or insurance value

Providing opportunities for survival in changing environments



Hotspots (emergency room) of Biodiversity

A biodiversity hotspot is a region with a high level of endemic species

Criteria for determining hotspots:

1. Regions that have at least 1,500 species of vascular plants that are endemic

(found only in that area)

2. Regions that have lost at least 70 percent of their original habitat

Hotspots are spread all over the world, the majority are forest areas and most are located inthe tropics

Conservation International identifies 25 such hotspots in tropical and temperate regions

around the globe.

They covers 2.3 percent of Earth's land surface but are home to at least 150,000 endemic

plant species (50 percent of the world's total number of plant species) and nearly 12,000

terrestrial vertebrates (42 percent of the world's total number of terrestrial vertebrates)

About 10 percent of the original area of world biodiversity hotspots is currently protected as

parks or reserves.



Hotspots in the World



Thar desert - The climate and vegetationin this areais a contrast to the Himalayan region.

Western Ghats - One of the twobiodiversity hotspots in India.

Sunder bans - The largest mangroveforest in India.

Chilika - This wetland area is protectedunder the Ramsar convention.

Himalayas - This majestic range ofmountains is the home of a diverse rangeof flora and fauna. Eastern Himalayas isone of the two biodiversity hotspots inIndia.

Hotspot regions in India



There are two hotspots present in India

The whole of Eastern Himalayas, there are an estimated 9000 plant species, with 3500

(i.e. 39%) of them being endemic. In India’s sector of the area, there occur some 5800

plant species, roughly 2000 (i.e. 36%) of them being endemic

At least 55 flowering plants endemic to this area are recognized as rare, for example,

the pitcher plant ( Nepenthes khasiana)

The area has long been recognized as a rich centre of primitive flowering plants

The area is also rich in wild relatives of plants of economic significance, e.g. rice,

banana, citrus, ginger, chilli, jute and sugarcane. The region is regarded as the centre of

origin and diversification of five palms of commercial importance namely, coconut,

arecanut, palmyra palm, sugar palm and wild date palm.

The ‘taxol’ plant Taxus wallichiana is sparsely distributed in the region and has come

under red data category due to its over exploitation for extraction of a drug effectively

used against cancer.

The Eastern Himalayas



As regards faunal diversity, 63% of the genera of land mammals in India are know

from this area. During the last four decades, two new mammals have been discovered

from the region: Golden Langur from Assam – Bhutan region, and Namdapha flying

squirrel from Arunachal Pradesh indicating the species richness of the region

The area is also a rich centre of avian diversity – more than 60% of the Indian birds are

recorded in the North East. The region also has two endemic genera of lizards, and 35

endemic reptilian species, including two turtle.

The western Ghats

The Western Ghats region is considered as one of the most important biogeographic

zones of India, as it is one of the richest centres of endemism

About 1500 endemic species of dicotyledonous plants are reported from the Western

Ghats. 245 species of orchids are found here, of which 112 species are endemic to the

region



As regards the fauna, as many as 315 species of vertebrates are endemic, these include

12 species of mammals, 13 species of birds, 89 species of reptiles, 87 species of

amphibians and 104 species of fish

The extent of endemism is high in amphibian and reptiles. There occur 117 species of amphibians in the region, of which 89 species (i.e. 76%) are endemic. Of the 165

species of reptiles found in Western Ghats, 88 species are endemic

Rare fauna of the region includes: Lion Tailed Macaque, Nilgiri Langur, Nilgiri Tahr,

Flying Squirrel, and Malabar Gray Hornbill

Lion Tailed Macaque

Renethera imschortians

(Red Vanda)

The Malabar Tree Nymph



Biodiversity at Global, National and Local levels

South Nations: Bio-rich

Northern Nation: Low level of Biodiversity

World ranking of mega-biodiversity countries



India as a mega diversity nationAmong the biologically rich nations, India stand among the top 10 or 15 countries for its

great variety of plant animals, many of which are not found elsewhere.

India has 45,000 plant species, of which most are angiosperms (15th rank in the world). These

include especially high species diversity of ferns (1022 species) and orchids (1082 species).

India has 50,000 known species of insects, including 13,000 butterflies and moths.

Comparative statement of recorded number of animal species in India & the WorldTaxa Species World Percentage of India to

the world

India’s world Ranking

Protista 2577 31259 8.24

Mollusca 5070 66535 7.62

Arthropoda 68389 987949 6.9

Other

Invertebrates

8329 87121 9.56

Protochordata 119 2106 5.65

Pisces 2546 21723 11.72

Amphibia 209 5150 4.06 15th

Reptilia 456 5817 7.84 5th

Aves 1232 9026 13.66 8th

Mamalia 390 4629 8.42 8th



Apart from the high biodiversity of Indian wild plants and animals there is also a

great diversity of cultivated crops and breeds of domestic livestock

The traditional cultivars included 30,000 to 50,000 varieties of rice and a number

of cereals, vegetables and fruit

The highest diversity of cultivars is concentrated in the high rainfall areas of the

Western Ghats, Eastern Ghats, Northern Himalayas and the North-Eastern hills.

Gene-banks have collected over 34,000 cereals and 22,000 pulses grown in India

India has 27 indigenous breeds of cattle, 40 breeds of sheep, 22 breeds of goats

and 8 breeds of buffaloes.

2nd lecture on biodiversity

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