Vegetation-environment relationships in a South Asian tropical montane grassland ecosystem: restoration implications

摘要

We studied the role of environmental factors driving species distributions, community structure, and ecosystem properties in an endangered montane grassland ecosystem in the Nilgiris, Western Ghats. We examined plant composition, ecosystem properties and environmental factors in one of the largest grassland sites in the Nilgiris. Ordination analysis showed that environmental gradients, mainly slope and aspect, controlled the distribution of the dominant plants. Some of the abundant species showed mutually exclusive distributional patterns along gradients, and some species exhibited distinct association with other species suggesting similar environmental tolerances. Classification analysis identified four community types, but ordination revealed that these communities formed a continuum along environmental gradients. Slope and soil depth strongly influenced aboveground biomass while species composition was influenced by the aspect. This study provides baseline data on grassland communities in the Nilgiris, and the results suggest that restoration activities should factor in environmental preferences of the plants as well as natural species associations.