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Forests and Biodiversity
The forest cover of the country, as per the present assessment, is 63.73 million ha. constituting 19.39% of the geographic area, out of which 37.74 million ha (11.48%) is dense forest, 25.50 million ha (7.76%) open forest and 0.49 million ha (0.15%) mangroves. Madhya Pradesh accounts for the largest forest cover of the country i.e. 20.68% followed by Arunachal Pradesh (10.80), Orissa (7.38%), Maharashtra (7.32%) and Andhra Pradesh (6.94%). The seven North-Eastern states together comprise 25.70% of the total forest cover.
The total recorded forest area of the country as reported by the State/Union Territory (UT) forest departments is 76.52 million ha. The forest cover as per the last assessment of the FSI (SFR, 1999) however, was 63.34 million ha. In most of the states, the forest cover is less than the recorded forest area. However, in the states of Arunachal Pradesh, Jammu & Kashmir, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim and the union territory of Andaman & Nicobar Islands, the forest cover is more than the recorded forest area.
The Indian region is one of the most diverse biogeographic regions of the world, embracing a wide range of topography from perpetually snow covered high Himalayan ranges to plains at sea level, low lying swamps and mangroves, inland systems, tropical evergreen rain forests, fertile alluvial plains, hot deserts and high altitude cold deserts. There are almost rainless areas, to the world's highest rainfall areas. The climate ranges from tropical and sub-tropical in Indo-Gengetic plains and peninsular regions to temperate and arctic in the Himalayan region. The habitat types vary from the humid tropical Western Ghats to the hot deserts of Rajasthan, from cold deserts of Ladakh to the long, warm coast line stretches, peninsular India.
A great variety of climatic and altitudinal variations coupled with varied ecological habitats have contributed immensely to the rich vegetational wealth, and varied flora and fauna generating thus a very unique biodiversity.
India is one of the 12 regions of diversity of crop plants in the world (Zeven and de Wet, 1982).
In addition, the Indian agri-diversity has been enriched by a continuous stream of introductions of new crops and cultivars since ancient times.
Thus enormous diversity had been built up which consists of the genepool of indigenous crop plants, their wild relatives and the well adapted introductions.
India ranks 7th as far as the number of species contributed to agriculture is concerned. India has been a primary centre of domestication for rice, sugarcane, benana, tea, mangom cucumber, citrus, jute, minor millets, vignas, brassicas, jack fruit, aloeasia, colocasia, cardamom, black pepper, ginger, turmeric, cucurbits, bamboos, etc. and a secondary centre of domestication for sesame, tomato, potato, maize, soyabean, etc.
McNeely et al. (1990) estimated that 70% of the world's total flowering plants occur in 12 countries and these have been designated as the Mega-diversity centres or Mega-diversity countries.
India is one of the 12 mega diversity countries. With only 2.4% of the global land area, India possesses more than 45,500 plant species, representing about 11% of the world's biota.This is only a rough estimation, since many of the organisms, especially in lower groups like-bacteria, fungi, algae, lichens, bryophytes, etc. have yet to be described and many remote geographical areas have to be adequately surveyed. In terms of plant diversity, India ranks 10th in the world and 4th in Asia.
Nearly 32% of India's biowealth is constituted by fungi (18.23%) and angiosperms (13.50%). It is estimated that over 45,500 species of plant species are accounted for in India which represent more than 10% of the known plant species of the world.
The flowering plants of India comprise about 17,500 species, which represent more than 6% of the world's known flowering plants. About 315 families of higher plant groups (of about 500 now recognised) and more than 4000 genera of flowering plants are known to occur in India in different ecosystems from the humid tropics of Western Ghats to the alpine zones of the Himalayas and from mangroves of tidal Sundarbans to the dry desert of
Rajasthan.
A significant feature of the Indian flora is the present of species from surrounding countries like - Malaya, Tibet, China, Japan, Europe, Africa, etc. and even from far widely separated countries like - U.S.A. and Australia.
India possesses little more than 7 per cent of the total animal species of the world. This percentage is higher than that of the plant species. Several invertebrate phyla, viz., Nemertinea, Nematomorpha, Pogonophora, Priapulida and Pentastomatida are yet to be reported from India. Out of total 86,874 animal species of this country Insects alone comprise 68.32 per cent and Chordates only 5.70 per cent.
34.90 per cent of insect species are endemic to the Indian region whereas more than 40 per cent of Indian leech and, freshwater sponges and molluscs also show endemism. Among vertebrates highest degree of endemism at species level is seen in Amphibia followed by Reptilia, Aves, Mammalia and Pisces.
Courtesy www.wwfindia.org
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