Class 10 Geography


Forest and Wildlife Resources: Biodiversity in India

Biodiversity: The variety of flora and fauna in a given geographical area is called biodiversity of that area. Some places are rich in biodiversity, while some others are poor in biodiversity.

For example; the Amazon rainforest is rich in biodiversity but that is not the case with the Sahara Desert.

Biodiversity in India

India is one of the world’s richest countries in terms of its vast array of biological diversity, and has nearly 8 per cent of the total number of species in the world (estimated to be 1.6 million). India is a Megadiverse Country, a name given to 17 countries which have very high biological diversity.

Biodiversity in India

India is home to 80,000 species of fauna, i.e. animals and 47,000 flora, i.e. plants. There are 34 biodiversity hotspots in India. A biodiversity hotspot is a region which has rich biodiversity threatened by human activities. This is evident from the fact that 10% of flora and 20% fauna in India come under threatened category.

List of Critically Endangered Species:

Cheetah, pink-headed Duck, Mountain Quail, Forest Spotted Owl, Madhuca insignis (wild mahua), Hubbardia heptaneuron (a grass species)

Number of Endangered Species: 79 species of mammals, 44 of birds, 15 of reptiles, and 3 of amphibians, 1,500 plant species are considered endangered.

Classification Based on IUCN
International Union for Conservation of Nature and Natural Resources

Normal Species

If the population level of species is within normal range for their survival, it is called normal species, e.g. cattle, pine, sal, rodents, etc.

Rare Species

A species can slip from the category of normal species to that of rare species. If the population of a species so small that it can become vulnerable or endangered, it is called rare species, e.g. Himalayan brown bear, wild Asiatic buffalo, desert, fox, hornbill, etc.

Vulnerable Species

If the population of a species has declined to such a level that it is likely to become endangered; it is called vulnerable species, e.g. blue sheep, Asiatic elephant, Gangetic dolphin, etc.

Endangered Species

Species which are in danger of extinction are called endangered species, e.g. black buck, crocodile, Indian wild ass, Indian rhino, lion tailed macaque, sangai (brow anter deer in Manipur), etc.

Extinct Species

A species which no longer exists is called an extinct species. A species may be extinct from a local area, region, country, continent or the entire earth. Examples: Asiatic cheetah, pink head duck, etc.

Note: A normal species can become rare species which can further slip to the categories of vulnerable species and endangered species in that order. (Normal Species → Rare Species → &Vulnerable Species → Endangered Species)

Endemic Species

A species which is found only in a particular geographical area is called an endemic species, e.g. Andaman teal, Nicobar pigeon, Andaman wild pig, mithun in Arunachal Pradesh, etc. Kangaroo is endemic to Australia.

Vanishing Forests

Causes of Depletion of Flora and Fauna:

Agricultural Expansion

According to the Forest Survey of India, over 262,000 sq km of forest area was converted into agricultural land in India between 1951 and 1980. Moreover, a substantial part of the tribal belts has been deforested or degraded by shifting cultivation. Destruction of forest results in loss of habitat for many species.

Enrichment Plantation

Enrichment plantation was done to promote a few favoured species in many parts of India. This practice involves plantation of a single commercially valuable species. This is also called monoculture plantation. This leads to elimination of other species and also results in loss of biodiversity.

Development Projects

Large scale development projects have also contributed significantly to the loss of forests. Over 5,000 sq km of forest was cleared for river valley projects since 1951. 40,000 hectare of forest would be inundated by the Narmada Sagar Project in Madhya Pradesh. You may have read in science lessons that hydroelectric project results in inundation of a very large area of forest. This always proves detrimental to the biodiversity of the affected area.

Mining

Mining has also caused large scale depletion of flora and fauna in many areas. Open cast mining results in long lasting scars on the surface of the earth. Are affected area is robber of all the forest cover. This results in loss of habitat for many species. For example; the ongoing dolomite mining is seriously threatening the Buxa Tiger Reserve in West Bengal.

Unequal Access to Resources

Social inequality is another major factor of depletion of flora and fauna. The rich people consume much more than the poor and thus cause a higher degree of environmental damage.

Social Effect of Resource Depletion: