Predicting Drought Responses of Dipterocarp Species Based on Plant Water-Use Traits in Peninsular Malaysia

Towards climate change adaptations in forestry across Southeast Asia, assessing the responses of timber species to changing environments is necessary.In this study, the responses of photosynthetic parameters and wilting status to soil desiccation and their linkages to plant water-use traits were evaluated using the saplings of eight dipterocarp species that are important resources for wood production.In all species, a decline in stomatal conductance occurred at least soil desiccation, followed by a decrease in electron transport rate, whereas severe photoinhibition and leaf wilting finally occurred at the most severe soil desiccation.These responses significantly differed among species, and they were associated with leaf-and stem-level water-use traits.Species that can avoid drought stress at the leaf level under desiccating conditions maintained photosynthetic metabolism and avoided wilting in drier soils.The abovementioned results indicate that organ-level water-use traits can be used as rapid indicators of the drought responses of dipterocarp species.