Salim Ali School of Ecology and Environmental Sciences, Pondicherry University, Pondicherry 605 014, INDIA.
Unlike the relatively species-poor temperate forests, the study and characterization of species-rich tropical forests are far more a complex task. Ecological research on vegetation, floristic diversity, tree distribution, and forest structure etc. are inadequate on the Eastern Ghats of south India, as compared to the Western Ghats.
The present comparative study on woody species diversity generated quantitative data on two tropical semi-evergreen forests. The two forests have some commonality and differences among the variables studied. The quantum of rainfall and soil fertility status varied. A total of 16 species were common to both the sites, but the kinds of predominant tree species varied between the two sites.
The biotic pressure in VM and SM sites was greater in sites closer to human settlements. Besides letting cattle for browsing, other human interferences in the sites like collection of medicinal plants such as Terminalia bellirica, T. chebula, Strychnos nux-vomica (in VM) and Sandalwood, and selective felling of Pterocarpus marsupium, Persea macrantha etc. (in SM) were noticed. Such resource extractions tax on forest biological diversity and regenerative potential of species. Shifting cultivation practised in site VM reduces potential forest area annually. This forest also harbours its own diverse animals and birds. On account of the floristic richness and associated fauna, these unique pockets of semi-evergreen forests deserve to be conserved as a genetic reservoir of the wild species.
The Vellimalai (VM) forests, in particular, should be declared a protected area (as presently it is under private forest act) to save the forests and their biota, for an effective management and biological conservation of species.