Greenhouse gas fluxes before and after Hurricane Maria

We used several methods to estimate forest damage in the neighborhood of each focal tree in order to test whether there may be a relationship between GHG fluxes and local damage severity. First, we assigned each damage category a numeric value of damage based on % canopy damage (Light = 0%-25%, Medium = 25%-75%%, and Heavy > 75%). We then calculated three mean neighborhood damage estimates for each gas sampling location by taking 1) the mean damage for all trees > 10 cm DBH in the same 20 x 20 m quadrat as our gas measurements; 2) the mean damage for all trees within a 10 m radius of our gas measurements; and 3) the mean damage for all trees within a 20 m radius of our gas measurements. We then fit simple linear models in R to test for significant relationships between CO2, CH4, and N2O and our neighborhood damage estimates.

Support for this work was provided by grants BSR-8811902, DEB-9411973, DEB-9705814 , DEB-0080538, DEB-0218039 , DEB-0620910 , DEB-1239764, DEB-1546686, and DEB-1831952 from the National Science Foundation to the University of Puerto Rico as part of the Luquillo Long-Term Ecological Research Program. Additional support provided by the University of Puerto Rico and the International Institute of Tropical Forestry, USDA Forest Service.