“How will you go about finding that thing, the nature of which is unknown to you?”
- Meno (Socratic dialogues)
Drought impact on forests
Climate change will increase the frequency and incidence of drought—periods when the soil moisture available to plants declines—and alter plant performance and composition. Seedlings are especially vulnerable to the detriments of drought. However, not all species respond equally to drought and these interspecific differences in drought tolerance can lead to changes in species composition in response to drought events. In addition, edge effects in fragmented forests can intensify the impacts of drought by making local conditions warmer and drier near forest edges compared to forest interiors. I am examining how species distributions along large-scale gradients of climatic drought and interspecific difference in drought tolerance of seedlings explains change in species performance between fragmented and intact forests and at forest edge vs. interior.
Edge effects and mechanisms that maintain diversity
The creation of forest edges modifies species composition and plant diversity in fragmented forests by altering tree species recruitment. Edge effects on tree recruitment are mainly thought to occur due to changes in abiotic conditions such as light and moisture, but few studies have examined whether edges affect the biotic interactions that mediate recruitment. In a tropical wet forest in the Western Ghats of India, I tested whether proximity to forest edges weakens the role of natural enemies, specifically insects and fungi, in diversifying the seedling community.
Functional traits and species response to gradients
The traits of organisms determine their response to abiotic and biotic stressors and therefore regulate differences among species in their survival and growth. In my PhD research, I tested whether traits explain differences in species recruitment at forest edge vs. interior, and whether recruitment differences correlate with trait-based variation among species in depredation by insects and fungi. Previously, I have also used trait-based approaches to study community assembly in temperate forests. I assessed whether traits explain species distributions in relation to environmental gradients and land-use intensity across a heterogeneous matrix of forests with different land-use histories and its consequences for functional diversity.
Resource harvest and forest health
In many forests across the globe, humans harvest Non-timber Forest Produce (NTFP) such as fruits, seeds, bark, and leaves. NTFP harvest is an important source of livelihood for many people but could harm the regeneration and persistence of harvested species. In evergreen forests of the Western Ghats, I am assessing harvester decisions regarding which NTFP to harvest, and where, when, and how much to harvest. For one heavily harvested NTFP, the fruit of the wild nutmeg Myristica dactyloides, I am comparing harvested and unharvested areas in their patterns of seedling recruitment and spatial organization of older trees.