Understanding the processes that influence spatial patterns in species
richness and composition is central to ecology. A wide range of mechanisms
have been proposed but the struggle to find a universal explanation for
these patterns continues. The wet evergreen forests of the Western Ghats
provide an ideal setting to test the drivers of large scale variation in
species richness. We collected primary data comprising 20,400 occurrences
of 450 species of woody plants, and built a biome-wide species database,
to examine patterns of richness and composition along the entire
latitudinal extent of the Western Ghats. This study uses a macroecological
approach with a focus on species geographic range to uncover the
mechanisms that shape the diversity and distribution of woody plants in
the Western Ghats. We then use spatial, edaphic, topographic and climatic
variables to test the relative importance of niche based and dispersal
based processes in structuring spatial variation in species composition.
Finally, using the primary data collected on species occurrence and range
size, we establish for the first time, baseline data on the status and
distribution of woody plants and, following the IUCN criteria, carry out
species assessments for 250 species of endemic woody plants of the Western
Ghats.