Understanding the Physiography, Bioclimate and Mapping of the Vegetation of the Chalakkudy River Basin, Anamalai part of Southern Western Ghats, India

  • Amitha Bachan Kandarumadathil Hyder Western Ghats Hornbill Foundation Indian Association for Angiosperm Taxonomy
Keywords: Bioclimate, Rainforest, Vegetation Mapping, River, Riparian, ecology, conservation


Vegetation of an area is determined by the overall interaction of the climatic, edaphic, and biotic factors. It is important to define the bioclimate of a region to understand the Vegetation dynamics of a region especially of the Tropical Monsoonal continents with complex physiography. It is a pioneering effort to understand bioclimate and primary   vegetation of a river basin from the southern Western Ghats region. Twenty years of rainfall data were analysed and geophysical features of the Chalakkudy River basin were analysed using GIS facility. The results provide more accurate data of the length, area and other physiographic features for the Chalakkudy River basin indicating need of updating of data of other river basins of Kerala. The bioclimatic data analyzed from 20 years of rainfall and vegetation maps indicate presence of dry-moist-forest zones to ever wet-rainforest regimes in the basin. The vegetation data shows 80% catchements of the river under forest category of which primary forests dominates with 519 Km2 (36%) followed by forest plantations 179.6 Km2 (12%), secondary forests 197.4 Km2 (17%), tea, coffee and other plantations constitute 198.3 Km2 (13%), degraded non forest vegetation 86.9 Km2 (6%) and reservoir, streams and rivers 46.5 Km2 (3%).  Of the 361 Km2 primary wet-evergreen (Rainforests) forests 294 Km2 is dense forest and 67 Km2 is degraded forests.

Author Biography

Amitha Bachan Kandarumadathil Hyder, Western Ghats Hornbill Foundation Indian Association for Angiosperm Taxonomy

Research Director

Western Ghats Hornbill Foundation


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