title: Airborne Laser Scanning Quantification of Disturbances from Hurricanes and Lightning Strikes to Mangrove Forests in Everglades National Park, USA.
abstract: Airborne light detection and ranging (LIDAR) measurements derived before and after Hurricanes Katrina and Wilma (2005) were used to quantify the impact of hurricanes and lightning strikes on the mangrove forest at two sites in Everglades National Park (ENP). Analysis of LIDAR measurements covering 61 and 68 ha areas of mangrove forest at the Shark River and Broad River sites showed that the proportion of high tree canopy detected by the LIDAR after the 2005 hurricane season decreased significantly due to defoliation and breakage of branches and trunks, while the proportion of low canopy and the ground increased drastically. Tall mangrove forests distant from tidal creeks suffered more damage than lower mangrove forests adjacent to the tidal creeks. The hurricanes created numerous canopy gaps, and the number of gaps per square kilometer increased from about 400~500 to 4000 after Katrina and Wilma. The total area of gaps in the forest increased from about 1~2% of the total forest area to 12%. The relative contribution of hurricanes to mangrove forest disturbance in ENP is at least 2 times more than that from lightning strikes. However, hurricanes and lightning strikes disturb the mangrove forest in a related way. Most seedlings in lightning gaps survived the hurricane impact due to the protection of trees surrounding the gaps, and therefore provide an important resource for forest recovery after the hurricane. This research demonstrated that LIDAR is an effective remote sensing tool to quantify the effects of disturbances such as hurricanes and lightning strikes in the mangrove forest.
authors.affiliation: Department of Environmental Studies & International Hurricane Research Center, Florida International University, Miami, FL 33199, USA. zhangk@fiu.edu.
authors.forename: Keqi
authors.initials: K
authors.lastname: Zhang
authors.affiliation: Caltech-Jet Propulsion Laboratory, MS 300-319D, 4800 Oak Grove Drive, Pasadena, CA 91109, USA.
authors.forename: Marc
authors.initials: M
authors.lastname: Simard
authors.affiliation: Department of Environmental Studies & Southeast Environmental Research Center, Florida International University, Miami, FL 33199, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Ross
authors.affiliation: Wetland Biogeochemistry Institute, Department of Oceanography and Coastal Science, Louisiana State University, Baton Rouge, LA 70803, USA.
authors.forename: Victor H
authors.initials: VH
authors.lastname: Rivera-Monroy
authors.affiliation: Department of Environmental Studies & International Hurricane Research Center, Florida International University, Miami, FL 33199, USA.
authors.forename: Patricia
authors.initials: P
authors.lastname: Houle
authors.affiliation: Department of Environmental Studies & Southeast Environmental Research Center, Florida International University, Miami, FL 33199, USA.
authors.forename: Pablo
authors.initials: P
authors.lastname: Ruiz
authors.affiliation: Wetland Biogeochemistry Institute, Department of Oceanography and Coastal Science, Louisiana State University, Baton Rouge, LA 70803, USA.
authors.forename: Robert R
authors.initials: RR
authors.lastname: Twilley
authors.affiliation: South Florida & Caribbean Network, Inventory and Monitoring Program, National Park Service , 18001 Old Cutler Rd. Suite 419, Miami, FL 33157, USA.
authors.forename: Kevin
authors.initials: K
authors.lastname: Whelan
keywords: Airborne light detection and ranging (LIDAR); Everglades; digital canopy model (DCM); forest disturbance; hurricane; lightning strike; mangrove