19.4 BIODIVERSITY AND CONSERVATION:

Conservation of Natural Resources:

The wise management of the biosphere for the benefit of all life in such a way that the natural ecosystems are maintained as well as utilized in a planned manner, is known as Conservation of Natural Resources.

Need of Conservation:

Indiscriminate and non-judicious exploitation of nature and natural resources in an unplanned manner by man has disturbed nature's balance. This is creating a condition of ecological crisis all over the world. Therefore, conservation through proper planned and judicious use of resources is essential.

The conservation aims at many aspects.

- It is required to maintain ecological processes and life support systems.

- It preserves quality of environment.

- It prevents wastage, spoilage of natural resources.

- It also improves and renews their quality along with usefulness.

- It preserves biological diversity.

- It ensures a continuous production of useful plants, animals and materials by establishing a balanced cycle of harvest and removal.

- It is essential for social and economic development.

Concept of Endangered Species:

The species or organisms whose number has been reduced to a critical level or whose habitats have been adversely affected so that they may become extinct if not given special protection are called endangered species. They are also called threatened species.

The International Union for Conservation of Nature and Natural Resources (IUCN) maintains a Red List or Red Data Book in which endangered species of plants and animals are reported.

IUCN has classified such species into four categories:

1 Endangered species,

2. Vulnerable species,

3. Rare species and

4. Indeterminate species.

Endangered Species are the species whose number of individuals is greatly reduced to a critical level. Its habitat is also drastically reduced due to unfavorable environment or human factors. As a result, it may become extinct if the causal factors continue. Asiatic wild ass, Psilotum nudum and Osmunda regalis are some examples of endangered species.

There are two types of causes of extinction namely natural and man made.

Natural cause of extinction include earthquakes, floods, landslides, volcanic activities, wild fire, etc.

The man-made causes responsible for extinction are mainly due to

- overexploitation of natural resources.

- Over-utilization or over-exploitation.

- Excessive cutting of forest trees,

- overgrazing, up-rooting of orchids and medicinal plants,

- over-fishing.

- Pollution of soil, water and air.

- hunting of Wild Animals such as tigers, lions, rhinos, cheetah.

- Destruction of Natural habitats by construction of dams and reservoirs, building of roads, mining activities, rail tracks, etc. These activities have decreased wild animal population considerably.

Native species of plants and animals have been badly affected by introduction of exotic species e.g. Congress grass ( Parthenium sp.) and Lantana camara - an exotic herb.

Other causes of extinction include the use of plant and animal species for pharmaceuticals, perfumes, cosmetics, decoration, medicines, tourism and tourist activities, ploughing of grasslands, etc. It is thought that 81 species of mammals, 38 species of birds and 18 species of amphibians and reptiles are endangered in India.

Conservation of biodiversity:

Conservation is defined as the management of the human use of the biosphere so that it may yield the greatest sustainable benefits to the present generation, while maintaining its potential to the needs of aspirations for the future generations.

The conservation aims at preservation of the quality of the environment. It also ensures the continuous yield of useful material by establishing balanced cycle of harvest and renewal.

The human beings are totally dependent on the nature for their requirements. The expanding population has increased the needs for more land to be brought under urbanization, industrialization and agriculture. This proliferation of man made structures in the forests has led to permanant loss of flora and fauna.

One of the major areas of concern is the complete loss of some of the species. Many of the species not known to us might have already faced extinction due to the destruction of their natural habitat. All organisms are linked in the food chain and interact with their biotic environment. Disappearance of a link upsets food chain disturbing the overall balance of ecosystem. Tehri dam project in UP has displaced over 85,000 people and immersed the Tehri town and 100 villages. Some other decisions like promoting " subabhul" and eucalyptus plantation also has proved a bane. Many useful projects like construction of dams also is responsible for this upset

The conservation of endangered species of plants and animals is necessary. It is also necessary to preserve biodiversity to maintain ecological processes, to maintain the number of individuals of a species, to build national economy and for the study of life in its natural habitat, etc.

There are two types of methods for conservation of endangered species:

1. In-situ conservation

2. Ex-situ conservation.

1. In-situ Conservation

It includes hot-spot methods which protect, preserve and restore endangered species in their own habitats in protected areas.

These methods include prohibition of grazing, cultivation and collection of products from the forests.

Maintenance of protected areas such as National Parks, Wild-life Sanctuaries and Biosphere Reserves is essential.

For example Tadoba National Park (Maharashtra), Corbett National Park (U.P.), and Kaziranga Wildlife Sanctuary (Assam), etc. In India there are about 80 National Parks and 441 Wild-life Sanctuaries covering about 107,310 sq. km. area . It accounts for 3.2% of India's total area. In Maharashtra there are 5 National parks and 11 sanctuaries.

2. Ex-situ Conservation

It is the conservation of endangered species outside their natural habitats is known as ex-situ conservation.

The endangered species are conserved outside their natural habitats at botanical gardens, culture collections and zoological parks.

It also considers preservation of gene pool, cells, tissues, etc. Endangered species can also be saved by giving priority over vulnerable species and such species over rare species. The habitats of the species should be safe-guarded by preventing human disturbances. Only those resources - which are eco-friendly should be allowed for use.

The endangered species are domesticated in protected areas and then introduced to their natural habitats. Man should be educated about the mportance and protection of wild-life. Strict implementation of provisions of Wild-life Protection Act, 1972 is mandatory. India was the first country to enact in this direction.

There are many examples of endangered Plant Species like Rauwolfia serpentina (Sarpgandha), Nepenthes khasiana (Pitcher plant), Drosera indica, Gnetum ula, Psilotum nudum, Osmunda regalis, Cycas bedomei.

There are many animals facing the danger of extinction. Great Indian Bustard, Musk deer or Antilope, Red fox, White-eyed duck, One-horned rhino (Rhinoceros unicornis), Asiatic wild ass, Red panda, Crocodile, etc