Diversity, distribution and need of urgent conservation of endemic plants in Himalaya

Abstract

The Himalaya is known for its unique and rich endemic plants. Diversity of endemic plants is considered for prioritizing areas including delineating the Biodiversity Hotspots and conservation implications. In view of limited authentic dataset on endemic plants, the study investigated the diversity and distribution patterns of endemic vascular plants of Indian Himalayan Region (IHR) and recorded a total of 1076 endemic plant taxa including 1061 angiosperms, 03 gymnosperms and 12 pteridophytes belonging to 432 genera and 100 families. Richness of endemic plants was found maximum in the Arunachal Pradesh (294), followed by Meghalaya (213) and Sikkim (212). Maximum number of endemic taxa was found in family Orchidaceae (115) followed by Asteraceae (79) and Poaceae (63). More than 81% endemic are recorded in mid elevation (1001–1500 m) altitude range. Among the recorded taxa, 28 species of IUCN viz. Critically endangered (9), Endangered (13), and Vuln-erable (3) categories. Endemic taxa having narrow distribution range, high use-value and low population density were prioritized for conservation implications. Amentotaxus assamica, Gymnocladus assamicus, Ilex venulosa, Pittosporum eriocarpum are recorded highest threat categories due to timber harvesting, unsustainable harvesting of fruits, habitat destruction, large-scale lime quarrying etc. Total 1258 grid cells (15′ × 15′) representing IHR were analysed to identify the endemic rich areas in the region. Based on the set criterion, 20 endemic rich areas were identified and maximum congruence of endemics recorded in Eastern Himalaya. Of the total, 69% endemic rich areas were covered under the Protected Areas and Biosphere Reserve Networks, however, remaining 31% were unprotected. Further, the conservation related studies are available only for 7% (88) and 2% (29) are having the propagation protocols (tissue culture and seed germination). In view of importance of conservation of endemic plants, the study recommends location-specific population assessment, in-situ and ex-situ conservation approaches, climate and anthropogenic impacts, reproductive biology for identifying the bottleneck and improving germination are required, before vanishing the endemic plant assets in Himalaya.