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Rock outcrops support specialist plant communities that are often adapted to highly seasonal climates and heterogeneous soil cover. However, the relationship between environmental parameters and plant functional types remains unexplored in many regions of the world, including the Northern Western Ghats (NWG) in India. In the present work, we characterised the vegetation of high and low elevation rock outcrops in the NWG, and investigate the relationship between plant functional types and environmental variables. Vegetation surveys were conducted on 16 high elevation and 14 low elevation sites using a transect and quadrat method. Floristic data were used to calculate plant diversity and plant functional type abundance. The relationship between vegetation and climatic (temperature, precipitation) and soil (soil carbon and nitrogen) variables was explored using cluster and ordination analysis. Rock outcrop sites were grouped into two clusters based on elevation, distance from the sea and mean diurnal range. Plant functional type abundance was related to macro-environmental variables such as temperature, precipitation and soil nutrients such as carbon and nitrogen. We inferred that the distribution and dominance of different plant functional types in the NWG are related to primarily by elevation (a proxy for temperature) and distance from the sea. [ABSTRACT FROM AUTHOR]

The northern section of the Western Ghats is a biodiversity hotspot with a predominance of rock outcrops. Although these outcrops are characterized by environmental extremes, they support a large diversity of species, many of which are endemics. High-elevation rock outcrops of the Western Ghats exhibit two lithotypes of distinct geological origins, namely basalt mesa (BM) and high-level ferricrete (HLF). We examined the interrelation between environmental factors, lithotypes and functional type abundance. We recorded 265,447 individuals belonging to 127 taxa categorized under seven plant functional types in 128 quadrats from sixteen high-elevation rock outcrops. Cluster analysis separated the sites based on the lithotypes. Graminoids and Therophytes were the dominant functional types across both the lithotypes. Latitude, seasonality, soil carbon and nitrogen were the influential environmental factors. Multivariate analysis of variance (MANOVA) showed that based on environmental characteristics, the two lithotypes are significantly different from each other. Different plant functional types were associated with different environmental variables, as shown by canonical correspondence analysis (CCA). Lithotype and levels of soil carbon and nitrogen together seem to shape the functional type abundance. Overall, we observed that there is a marginal difference in the vegetation across the two lithotypes of outcrops. The abundance of each plant functional type was deferentially associated with the seasonal environment and soil nutrients. [ABSTRACT FROM AUTHOR]