Session IV: Wetlands |
Abstract #: 97407 |
MODELING PERIPHYTON AND PHOSPHORUS LINKAGES IN THE EVERGLADES
Quan Dong, Paul McCormick, Fred Sklar
Everglades Systems Research Division, South Florida Water Management District
ABSTRACT
Native periphyton is a key ecosystem component in the Everglades. They have been identified as extremely sensitive to phosphorus supply. Periphyton are also being considered as the basis for ecological-engineering design of periphyton storm-water Treatment areas to reduce phosphorus in agricultural runoff. We are developing a periphyton model to study the relationship between periphyton community structure, production, phosphorus and other environmental conditions. This model serves as a quantitative framework that can (a) describe the system, (b) synthesize the current ecological information from empirical studies, (c) evaluate importance of various ecological processes and parameters, (d) identify critical links and missing links in current ecological understanding, and (e) generate hypotheses and projections. The design of the model allows users to perform different analyses with a minimum effort of modification. The structural complexity of the model can be controlled in different analyses depending upon the objectives and scales of each study. The model is applicable to characterizing the phosphorus-threshold and the retention capacity of phosphorus of the periphyton storm-water treatment areas. For example, our model analyses suggest that small gradual changes in phosphorus supply n a certain range may lead to a dramatic change (bifurcation) in the community structure and biomass of periphyton. Such a range is a parameter of the phosphorus-threshold.