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Tropical rainforests of India are found in the Andaman and Nicobar Islands,〔Andaman and Nicobar Islands coordinates: 〕 the Western Ghats,〔Western Ghats coordinates: 〕 which fringe the Arabian Sea, the coastline of peninsular India, and the greater Assam region in the north-east.〔Assam coordinates: 〕 Small remnants of rainforest are found in Odisha state.〔Odisha coordinates: 〕 Semi-evergreen rainforest is more extensive than the evergreen formation partly because evergreen forests tend to degrade to semi-evergreen with human interference. There are substantial differences in both the flora and fauna between the three major rainforest regions.〔(IUCN, 1986 Rodges and Panwar, 1988)〕 The Western Ghats monsoon forests occur both on the western (coastal) margins of the ghats and on the eastern side where there is less rainfall. These forests contain several tree species of great commercial significance (e.g. Indian rosewood ''(Dalbergia latifolia)'', Malabar Kino ''(Pterocarpus marsupium)'', teak ''(Tectona grandis)'' and Indian laurel ''(Terminalia crenulata)''), but they have now been cleared from many areas. In the rainforests, there is an enormous number of tree species; at least 60 percent of the trees of the upper canopy are of species which individually contribute not more than one percent of the total number. Clumps of bamboo occur along streams or in poorly drained hollows throughout the evergreen and semi-evergreen forests of south-west India, probably in areas once cleared for transporting agriculture. The tropical vegetation of north-east India (which includes the states of Assam, Nagaland, Manipur, Mizoram, Tripura and Meghalaya as well as the plain regions of Arunachal Pradesh) typically occurs at elevations up to . It embraces evergreen and semi-evergreen rainforests, moist deciduous monsoon forests, riparian forests, swamps and grasslands. Evergreen rainforests are found in the Assam Valley, the foothills of the eastern Himalayas and the lower parts of the Naga Hills, Meghalaya, Mizoram and Manipur, where the rain fall exceeds per annum. In the Assam Valley the giant Hollong ''(Dipterocarpus macrocarpus)'' and ''Shorea assamica'' occur singly, occasionally attaining a girth of up to and a height of up to . The monsoon forests are mainly moist sal ''(Shorea robusta)'' forests, which occur widely in this region.〔(IUCN, 1991)〕 The Andaman and Nicobar islands have tropical evergreen rainforests and tropical semi-evergreen rainforests as well as tropical monsoon forests.〔(IUCN, 1986)〕 The dominant species of Keruing wood is ''Dipterocarpus grandiflorus'' in hilly areas, while ''Dipterocarpus kerrii'' is dominant on some islands in the southern parts of the archipelago. The monsoon forests of the Andamans are dominated by the Andaman Redwood ''(Pterocarpus dalbergioides)'' and ''Terminalia spp''. Tropical forests in India's east present a total contrast with the pine and coniferous woodland of the Western Himalayas. The natural cover of India varies with altitude; these evergreen forests are bounded with high alpine meadows nearer to the snowline and temperate forests of short stout trees at lower elevations. In the Himalayan foothills are deciduous trees, with shrubs, bamboo, ferns and grass. India's northern plains, the course of the holy rivers Ganges and Yamuna; the Thar Desert in the west; the Sundarbans, the marshy swamplands, in the delta of the Ganges and the Brahmaputra, in the east; the Deccan Plateau, lying in the rain shadow of the hills and the Western Ghats with their dense; luxuriant forests – all provide fascinating variations in habitats. These forests sustain 350 species of mammals, 2,100 kinds of birds (both local and migratory), nearly 350 species of reptile and countless insects. The need for conservation of the environment and the forests has exercised the minds of Indian rulers from the earliest of times. In recent times, it was the administrators and princely rulers who demarcated and reserved forests as private preserves. Today many of the forested regions form the nucleus of India's wildlife sanctuaries and parks. Still, increasing population, hunting and encroachments continues to threaten India's forest lands. ==See also== * Indian Council of Forestry Research and Education 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Tropical rainforests of India」の詳細全文を読む スポンサード リンク
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