Factors affecting the concentration and flux of materials in two southern Everglades mangrove wetlands

Authors

Stephen E. Davis III, Department of Biological Sciences and Southeast Environmental Research Center, Florida International UniversityFollow
Daniel L. Childers, Department of Biological Sciences and Southeast Environmental Research Center, Florida International UniversityFollow
John W. Day Jr., Coastal Ecology Institute, Center for Coastal, Energy, and Environmental Resources, Louisiana State UniversityFollow
David T. Rudnick, Everglades Systems Research Division, South Florida Water Management DistrictFollow
Fred H. Sklar, Everglades Systems Research Division, South Florida Water Management District,Follow

Abstract

Concentrations and fluxes of C, N, and P were measured in dwarf and fringe mangrove wetlands along the Taylor River, Florida, USA from 1996 to 1998. Data from these studies revealed considerable spatial and temporal variability. Concentrations of C, N, and P in the dwarf wetland showed seasonal trends, while water source was better at explaining concentrations in the fringe wetland. The total and dissolved organic carbon (TOC and DOC), total nitrogen (TN), and total phosphorus (TP) content of both wetlands was higher during the wet season or when water was flowing to the south (Everglades source). Concentrations of nitrate plus nitrite (NOx –), ammonium (NH4 +), and soluble reactive phosphorus (SRP) in the fringe wetland were all highest during the dry season or northerly flow (bay source). Nutrient concentrations most effectively explained patterns of flux in both wetlands. Increased wetland uptake of a given constituent was usually a function of its availability in the water column. However, the release of NOx – from the dwarf wetland was related to the NH4 + concentration, suggesting a nitrification signal. Nitrogen flux in the dwarf wetland was also related to surface water salinity and temperature. Our findings indicate that freshwater Everglades marshes are an important source of dissolved organic matter to these wetlands, while Florida Bay may be a source of dissolved inorganic nutrients. Our data also suggest that temperature, salinity, and nutrient concentrations (as driven by season and water source) influence patterns of materials flux in this mangrove wetland. Applying long-term water quality data to the relationships we extracted from these flux data, we estimated that TN and TP were imported by the dwarf wetland 87 ± 10 and 48 ± 17% of the year, respectively. With Everglades restoration, modifications in freshwater delivery may have considerable effects on the exchanges of nutrients and organic matter in these transitional mangrove wetlands.

Comments

Copyright © 2003 Inter-Research.

This material is based upon work supported by the National Science Foundation through the Florida Coastal Everglades Long-Term Ecological Research program under Cooperative Agreements #DBI-0620409 and #DEB-9910514. Any opinions, findings, conclusions, or recommendations expressed in the material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Recommended Citation

Davis, S.E., D.L. Childers, J.W. Day, D.T. Rudnick, F.H. Sklar. 2003. Factors affecting the concentration and flux of materials in two southern Everglades mangrove wetlands. Marine Ecology Progress Series 253: 85-96.