A contribution to woody plant diversity of Doon Valley, Uttaranchal (North-West Himalaya).

摘要

Woody plant diversity of Doon Valley in outer Himalaya is represented by 674 taxa, 92 families and 368 genera. Total taxa include 591 trees, 35 shrubs, 12 climbers, 15 palms and 21 bamboos. Out of these, Gymnosperms are represented by 42 species and dicots by 596. Percentage-wise, Dicotyledons hold 88.42 share and Monocotyledons contribute 5.34. Gymnosperms are only 6.24 per cent of entire floristic composition. Interestingly Doon Valley perpetuates suitable climatic condition for luxuriant growth of both tropical species (Tectona grandis, Shorea spp., Phoenix spp. etc.) and temperate species (Pinus spp.). The cosmopolitan structure of flora is created by introduction or invasion of 31.15% exotics. Significant contribution to local flora is recorded by addition of 258 species to existing literature. Present study also contributes addition of 11 species to the existing list of Forest Research Institute Arboretum plants. Conservation potential and prospects of the flora have been appraised by identification and listing of 18 species which are declared as threatened in International Union of Conservation of Nature and Natural Resource (IUCN) Red List for the year 2003. Progenitors of 17 cultivated and economic plants have been listed for conservation of genetic resource. During field investigation 13 species have been identified threatened due to habitat loss while 7 species were found threatened due to massive exploitation..