ALIEN FLORA INTO THE FRAGILE ECOSYSTEM OF ANDAMAN AND NICOBAR ISLANDS: A MAJOR CONCERN

Abstract

The Andaman and Nicobar Islands epitomize a diverse Island biogeographic zone characterized by rich heritage of biological wealth. The Andaman and Nicobar Islands are evolved from volcanic eruptions and are continuity of ArakanYoma mountain of Myanmar and subsequently other Islands are of coral reef origin developed. As these Islands arevery far from any part of mainland and developed its own flora by evolution and also gathered flora of South East Asia.The insular flora of this archipelago consisting of about 2654 species belonging to 219 families and 1046 genus withina land area of 8249 km 2 on 572 Islands and islets is a momentous feature, making them a cynosure not only for planttaxonomists but also for conservationists. The rare and distinct flora which evolved through millions of years due tothe insular nature of the territory, physical isolation between the Islands and also from the neighboring continentallandmasses, is unique in India. It has been reported that there are 250 and above medicinal plants, 154 plant with edibleportions mostly used by tribes and there are 44 plants which can be directly recommended for cultivation or can beused in horticultural technologies. There are many wild relatives of horticultural importance, out of which 12 plantspecies are found endemic. Tribes of these Islands also use around 231 plant species parts as flock medicines. All theavailable literature on flora of Andaman and Nicobar Islands were scrutinized and a total of 592 introduced alien plantspecies of agricultural importance, dangerous weeds and other flora has been discussed in this paper including theirdamage to the fragile ecosystem and habitat destruction of native plant species.