| Session IV: Wetlands |
Abstract #: 97403 |
EVALUATING EVERGLADES ECOSYSTEM DYNAMICS WITH SPATIAL SIMULATION MODELS
Fitz, H. Carl, F.H. Sklar, Y. Wu
South Florida Water Management District
ABSTRACT
Whereas Everglades restoration efforts are being initiated, the complex interactions of physical, chemical and biological processes in this heterogeneous landscape are incompletely understood. Stormwater Treatment Areas (STAs) and modifications to the water control system will alter water and nutrients across space and time within the region. Our simulation models incorporate hydrologic, nutrient, and plant dynamics in order to evaluate the spatio-temporal patterns of landscape change associated with management alternatives. In our Everglades Landscape Modeling Program, we developed a general model with scaleable code and applied it to 1) WCA2A (the CALModel) and to 2) the combined area of the WCAs, part of Big Cypress, and Everglades National Park (the ELModel). In the current model development phase, we used CALM to analyze ecological dynamics of the wetlands of WCA2A, where data for parameterizing and calibrating the model are of the highest quality. In some examples of the model interactions and feedbacks, we saw that drydown and rewetting the soils modified bio- available nutrients which in turn affected the plant growth; altered macrophyte biomass in regions near nutrient inflows substantially affected water levels through differences in transpiration and overland flow. Under various scenarios of water and nutrient load changes associated with potential loads from the STAs, the distribution of water and soil nutrients, periphyton, and marsh graminoids were significantly different compared to the base case of no STA construction. Calibration and uncertainty analyses are underway, and the lessons learned from the CALM will be applied to the full ELM as another tool for preliminary evaluation of the C&SF Project Restudy in the next year.
