The world knows the kind of destruction that Hurricane Katrina brought to New Orleans and other cities and towns on the Gulf Coast. But destruction of a different sort is the subject of a study in the journal Science by Jeffrey Q. Chambers of Tulane University and colleagues. They report that the storm uprooted or severely damaged roughly 320 million trees, making an impact on the carbon balance in the region. The researchers analyzed satellite imagery from before and after the hurricane to determine the net change in ‘nonphotosynthesizing vegetation’ - in other words, the increase in dead wood and ground litter. Then they went to sample plots in the region’s forests, corresponding to data points from the images, and counted downed or damaged trees. ‘A lot of material moved from being a living tree to being litter,’ Dr. Chambers said. The findings have implications for the carbon footprint of the region’s forests. Through photosynthesis, living trees store carbon, but when they die they begin to decompose, and the action of those decomposing organisms releases carbon. While trees eventually grow back in a heavily damaged forest, Dr. Chambers said, ‘it takes a lot longer to recover […]