Authors: Xinyuan Wei*, Oak Ridge National Laboratory, Daniel Hayes, University of Maine, Xiaojuan Yang, Oak Ridge National Laboratory, Ricciuto Daniel, Oak Ridge National Laboratory, Yu Zhou, Clark University
Topics: Biogeography, Environmental Science, Soils
Keywords: Forest, Hurricane, Nutrient, Puerto Rico, Watershed
Session Type: Virtual Paper
Start / End Time: 4:40 PM / 5:55 PM
Room: Virtual 41
Presentation File: No File Uploaded
The global warming contributes to the increasing frequency and intensity of hurricanes. As a serious natural disturbance, the interaction of meteorological, physiographic, and biotic factors introduced by hurricanes result in complex patterns of damage in tropical forest regions. In addition, the accompanied heavy precipitations result in immediately increasing surface runoff and accelerate nutrients loading including nitrogen and phosphorous from soils to inland waters and eventually moved out of the watershed. In this synthesis, we compiled observational data sets (i.e., discharge, nitrogen concentration, and phosphorous concentration) from 15 watershed outlets in Puerto Rico generally spanning the time period from 1980 to 2017 as well as leaf area index and land cover data sets to analyze the instant and lagged effects of hurricanes on nitrogen and phosphorous exports from each watershed. Our results suggest that hurricanes immediately accelerated nitrogen and phosphorous exports from each watershed through suddenly increased surface runoff. Because hurricanes defoliated large forested area in each watershed and deposited more fine litter (leaves, small wood, and miscellaneous debris) on the forest floor, which significantly increased soil nitrogen and phosphorous density. Therefore, during the first post-hurricane year, the daily average nitrogen and phosphorus concentrations of the 15 watersheds were 26% and 22% higher than the pre-disturbance levels, respectively.