Remote sensing as a tool for estimating biodiversity

The adoption of the International Convention on Biological Diversity by India obliges us to inventory our country's biodiversity, make all attempts to conserve it and monitor the efficacy of these measures. This is an enormous task, for India harbours some 120 000 known and perhaps another 400 000 as yet undescribed species, which are distributed over its 320 million ha of Iand and 200 million ha of exclusive economic zone in the sea The use of remote sensing techniques would greatly facilitate such an exercise. These techniques can provide us with information about land cover, which can then be related to biodiversity. Such exercises have been attempted before, mainly in agricultural or crop areas, or in relatively species-poor forests, dominated by a few species We review the pertinent Studies, which use airborne sensors as well as satellite imagery. However, most of these techniques are not applicable to the task of inventorying the biodiversity of the Indian heterogeneous species-rich forests We suggest ah alternative methodology, employing a two step approach of (a) mapping the coverage of the entire landscape and seascape of the country in terms of landscape element types with the use of satellite imagery, and (b).sampling representative sets of landscape element types, to correlate these with biological communities, species and genes Our own pilot studies in the Karnataka Western Ghats suggest that the use of the IRS series satellite .imagery coupled to supervised classification can permit identification of landscape element types with distinctive composition in terms of biological species. We believe that this methodology is widely applicable, and suggest specific questions which need to be answered in order to extend this methodology over the countr