Hydraulic traits in seasonally dry tropical forests

Abstract

Water is essential to sustain plant growth and function, and its availability in space and time is critical in shaping tropical forests. Plant hydraulic traits provide helpful insight into the various strategies that have evolved in tropical species to deal with this varying water availability. Understanding these complex and not well-understood strategies is vital, especially given the unprecedented global increase in drought and associated large-scale forest dieback. In this thesis, I use a multispecies, multi-trait approach to study water-use strategies and drought tolerance in tropical forests. I discuss pan-tropical patterns of risk of hydraulic failure (Chapter 2), compare two Indian tropical forests differing in rainfall seasonality to understand community-level differences in risk of hydraulic failure (Chapter 3), highlight key understudied leaf-level responses to drought (Chapter 4) and examine the role of light availability in determining species responses to low water conditions (Chapter 5). This thesis reports for the first time hydraulic trait measurements of species from the South-Asian tropical forests, which provide disproportional services to sustain life both locally and globally.