PARENT SESSION
Poster Session # 14: Forest Ecology.
Wednesday, August 6 Presentation from 5:00 PM to 6:30 PM. SITCC Exhibit Hall B.
Structural, functional characteristics and resilience of forest ecosystems.
Beard, Karen*,1, Vogt, Kristiina, Vogt, Daniel2, Scatena, Frederick3, Covich, Alan4, Sigurdardottir, Ragnhildur5, Siccama, Thomas5, Crowl, Todd1, 1 Utah State University, Logan, UT, USA2 University of Washington, Seattle, WA3 University of Pennsylvania, Philadelphia, PA4 Colorado State University, Fort Collins, CO5 Yale University, New Haven, CT
ABSTRACT- We conducted an experimental manipulation in the Luquillo Experimental Forest, Puerto Rico, to test hypotheses on the effect of hurricane disturbance on ecosystem processes. Our experimental treatments consisted of wood addition, removal and control plots, because wood addition is a major consequence of hurricane disturbance. Our ecosystem indicators included: tree growth by species, litterfall, leaf litter decomposition rates, and root turnover. We found that the effect of coarse wood in ecosystem resilience varied across the Luquillo landscape. For example, in one site there was no influence on tree species growth rates by removing or adding coarse wood while in two other sites the removal of wood resulted in decreased growth rates and the addition of wood increased their annual productivity. We found that part of the variability measured in ecosystem response to disturbances and their recovery rate were controlled by legacies that maintain a stronger constraint on the functioning of the system than that imposed by the disturbance. For example, stream geomorphology controls the type of riparian zone produced and created distinct legacies. Legacies are also produced by soil chemistry, coarse wood, and individual plant life history strategies.
Key words: legacy effect, Luquillo Experimental Forest, hurricane, disturbance