BayCEER Workshop 2023

canceled

Local variation of soil moisture and light in fragmented forests

P 3.2 in Zooming in: Small scale findings

Tropical forests house about 50% of terrestrial biodiversity and are responsible for a third of productivity. Human activities that fragment these forests are a threat.Fragmentation may alter the availablity of light and water for seedlings which may benifit some species and negatively affect other species. Despite studies showing the role of drought in seedling dynamics, the relative roles of soil moisture and light for seedling dynamics, and community composition in fragmented forests are yet to be determined.

 In this study, we examined the variation of light and soil moisture, and coordination of drought and shade tolerance in seedlings. Our study site is in a human modified fragmented landscape, in the Western Ghats, a biodiversity hotspot of peninsular India. We measured gravimetric water contents and canopy openess in 250 plots and in situ soil water potentials in 58 plots along edges gradient. Unexpectedly, our initial results show no variation in light and soil moisture across an edge gradient implying that these factors don't shape seedling diversity with respect to edges in this area. we use a trait based approcah to evaluate the coordination of tolerance to drought and shade in seedlings of 16 tree species. Our initial results indicate a positive trend between seedling drought and shade tolerance. They support the notion of generalized tolerance against different stressors as a main life history strategy.

The relationship of trait syndromes to seedling distribution and performance will help us gain insights into the role of light and water in shaping seedling dynamics and regeneration in fragmented forests in current and future climate conditions.

Keywords: Fragmentation, Edge-effects, Trait co-ordination