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bioRxiv · 10.1101/2025.07.23.666346

Aspect influences vegetation type in the Western Ghats

Abstract

Western Ghats (WG) of India is one of the important biodiversity hotspots characterized by high levels of species endemism. The length of the rainy season and total rainfall are known to influence regional scale vegetation pattern. A recent study identified two aspect-related modes that influence landscape-scale tree cover (TC) and canopy height (CH) in the WG: north-facing slopes have a higher TC and CH than the south-facing slopes and (ii) higher TC and CH on the west-facing slopes than the east-facing slopes. However, it remains unclear whether these aspect-related asymmetries extend to the vegetation types. Here, with the help of seasonal NDVI variations, we demonstrate that aspect influence vegetation type as well. In general, north and west facing aspects support higher proportion of evergreen forests than the south and east facing slopes. In contrast, the dry deciduous and thorn forests relatively dominate the south and east-facing slopes. This natural heterogeneity in the vegetation type linked to aspect needs to considered while designing ecological research and management plans in the WG.

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Maheshwori, D., Managave, S., Jathar, G., Davande, S.. 2025-07-27. Aspect influences vegetation type in the Western Ghats. https://doi.org/10.1101/2025.07.23.666346

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