Tropical tree species differ in damage and mortality from lightning.

Abstract

Lightning is an important agent of mortality for large tropical trees with implications for tree demography and forest carbon budgets. We evaluated interspecific differences in susceptibility to lightning damage using a unique dataset of systematically located lightning strikes in central Panama. We measured differences in mortality among trees damaged by lightning and related those to damage frequency and tree functional traits. Eighteen of 30 focal species had lightning mortality rates that deviated from null expectations. Several species showed little damage and three species had no mortality from lightning, whereas palms were especially likely to die from strikes. Species that were most likely to be struck also showed the highest survival. Interspecific differences in tree tolerance to lightning suggest that lightning-caused mortality shapes compositional dynamics over time and space. Shifts in lightning frequency due to climatic change are likely to alter species composition and carbon cycling in tropical forests.