| Popis: |
FHANTM (Field Hydrologic And Nutrient Transport Model), FHANTM 2.0 (FHANTM version 2.0), and EAAMOD-FIELD (A Flow and Phosphorus Model for High Water Tables) are field-scale water quality models developed specifically for south Florida conditions. These models predict water table levels, discharge, and phosphorus loads in response to weather, soil, land use, and nutrient management conditions. FHANTM has been used in the Lake Okeechobee regulatory program for evaluating high phosphorus discharge sites north of Lake Okeechobee. Most sites were formerly dairies or were heavily stocked with beef cattle in the past. These sites have flat topography, sandy soils, high water tables, and a moderate drainage system. FHANTM 2.0, which is significantly different from FHANTM, was developed for generalized use in modeling beef/calf operations. EAAMOD-FIELD has undergone extensive development and testing in the Everglades Agricultural Area (EAA) south of Lake Okeechobee. The EAA has a flat topography, organic (histosols) soils, high water tables, and an extensive drainage system. To ensure that the regulatory program was using the best model available, a comparison was made among FHANTM, FHANTM 2.0, and EAAMOD-FIELD. Model documentation and algorithms were reviewed. Simulated surface runoff and phosphorus loadings were compared to measured data for two sites from April 1989 through December 1991. Statistical correlation of monthly and annual values was analyzed. Based on model review and data analyses, we concluded that EAAMOD-FIELD was the best model to use for the regulatory program. |
