Quantifying mortality of tropical rain forest trees using high-spatial-resolution satellite data


* OTS-Interlink 341, P.O. Box 025635, Miami, Florida 33102, USA
E-mail: dbclark@sloth.ots.ac.cr


Assessment of forest responses to climate change is severely hampered by the limited information on tree death on short temporal and broad spatial scales, particularly in tropical forests. We used 1-m resolution panchromatic IKONOS and 0.7-m resolution QuickBird satellite data, acquired in 2000 and 2002, respectively, to evaluate tree death rates at the La Selva Biological Station in old-growth Tropical Wet Forest in Costa Rica, Central America. Using a calibration factor derived from ground inspection of tree deaths predicted from the images, we calculated a landscape-scale annual exponential death rate of 2.8%. This corresponds closely to data for all canopy-level trees in 18 forest inventory plots, each of 0.5 ha, for a mostly-overlapping 2-year period (2.8% per year). This study shows that high-spatial-resolution satellite data can now be used to measure old-growth tropical rain forest tree death rates, suggesting many new avenues for tropical forest ecology and global change research.