Research carried out in Puerto Rico’s dry forest after Hurricane Maria shows how trees recover after hurricanes by growing leaves that absorb light and carbon dioxide more efficiently:
Some tree species heal from the ravages of hurricane damage by growing replacement leaves optimized for greater efficiency, according to a Clemson University field study presented at the British Ecological Society’s annual conference.
This new, optimized growth is an apparent attempt to fight back when hurricane winds rip away limbs and leaves.
When Hurricane Maria hit Puerto Rico last year, ecologists at Clemson’s Belle W. Baruch Institute of Coastal Ecology and Forest Science in Georgetown, South Carolina, took the opportunity to study how hurricanes affect tropical dry forests in the Caribbean. The worst natural disaster on record to affect the U.S. territory, the hurricane stripped numerous trees bare of their leaves and disrupted their ability to absorb the light needed for growth and survival.
The preliminary findings suggest that 11 of 13 species studied were taking in carbon dioxide at much higher rates immediately following Hurricane Maria. Many had also changed key characteristics of their leaves, including increasing leaf area relative to leaf biomass investment. Simply put, trees were able to capture the same amount of light while spending less energy on leaf production.
Overall, Caribbean tropical dry forests seem to be capable of tolerating major hurricanes, though the ecologists stressed that there may be winners and losers in terms of how species respond.
Currently it is unclear whether dominant evergreen species can exploit post-hurricane conditions to the same extent as deciduous species, according to Allerton.
“Many of our evergreens displayed little change in gas exchange rates and in general the relative decline in new leaf chlorophyll after Maria was much greater than for deciduous species,” he said. “Under normal conditions, evergreens renew their canopies over monthly and yearly timescales, therefore it’s likely hurricane canopy damage is a more expensive process for these trees.”
As climate change leads to expected increases in hurricane frequency and intensity, the species composition of tropical dry forests in the Caribbean is likely to change. One concern is whether endemic species will disappear over time.
Get more information in the full media release from Clemson University.
[Image: Mark Yokoyama]