Dramatic variability in Katrina-induced mortality in the Pearl River basin. Cypress-tupelo swamp forests in swales and other low-lying sites experienced little damage whereas adjacent bottomland hardwood forest suffered extremely high mortality (high resolution aerial imagery from LSU’s GIS Information Clearinghouse). Initial results from this project will be published in the 16 Nov 2007 issue of Science.
High tree mortality in a bottomland hardwood forest of the Pearl River basin caused by hurricane Katrina. Invasive Chinese tallow trees, visible in the background, are rapidly colonizing these disturbed areas.
National Institute for Climate Change Research
Hurricane Impacts on Structure and Functioning of Southeastern Forest
The primary goals of this project are to: (i) Develop empirical relationships between wind-field parameters and species-specific tree mortality rates for Major (Saffir-Simpson Category 3-5) hurricanes striking the Southeastern Region, (ii) Modify an ecosystem simulation model (Ecosystem Demography – ED) to allow simulation of catastrophic hurricane-driven tree mortality dynamics; (iii) Develop a set of hurricane scenarios based on historical records and possible future trends driven by natural cycles and anthropogenic climate change, and employ ED to predict forest carbon balance impacts from these scenarios; and (iv) Utilize hurricane events that are likely to strike the Southeastern Region during the course of this study to further expand and test empirical relationships and model predictions.
The overall working hypothesis is that disturbance related to hurricane activity in the Southeastern Region has significant negative impacts on forest carbon balance and the regional carbon sink, and that expected future changes in the hurricane disturbance regime will further degrade the Southeastern Region carbon sink.
project will employ a synthetic approach combining field-based tree
damage investigations, remote sensing image analyses, and an ecosystem
simulation model. Forest inventory
analysis methods will be employed to estimate biomass loss from damage
mortality. Spatial variability in
mortality rates will be correlated to hurricane wind-field parameters
regression methods. Remote sensing
investigations using spectral mixture analysis on non-photosynthetic
endmembers will provide maps of disturbance variability within
classes, and allow further development of tree mortality probability
distribution functions. A modified ED
model will allow integration of results, and be used to explore
future hurricane scenarios on Southeastern Region forest carbon balance.
deliverables include: (i) A
plots for Major hurricanes striking the Southeastern Region. (ii)
Atmospherically corrected remote sensing images (e.g. ALI, Hyperion,
relative abundance maps of disturbed areas within footprints of Major
A modified ED model
allowing simulation of past hurricane events and future scenarios.