The Effect of a Pulsed Rainfall Regime on Dry Forest Tree Seedlings
Lalitha Krishnan, Mahesh Sankaran
Semi-arid dry forests are one of the most rapidly disappearing vegetation types in India. Pulsed rainfall patterns resulting from climate change are altering the environmental conditions that tree species have to survive under. This pilot study aimed to identify the tree species that will thrive under these new conditions, in order to inform management decisions about maintaining these habitats.
In this pilot study, 30 seedlings from 5 dry deciduous tree species were grown in PVC pipes and were subjected to a continuous (C), and a large pulsed treatments (L) for two months. During the study several functional traits were measured including SLA, stomatal density, leaf N, root:shoot ratio and photosynthesis measurements, as well as vegetative growth and total biomass.
SLA and leaf N were not able to predict species-wise differences in number of leaves between the the continuous and large pulse treatments. However different species did respond differently and it may be possible to allocate different strategies to the different species when more individuals and species are used.
Using these functional traits it is possible to characterise the responses of different tree species to pulsed rainfall patterns. Those species which are drought tolerant and utilise drought avoidance strategies will be able to cope well. Hence the larger study will informative as to which tree species are likely to be able to tolerate future climate scenarios.