An Application of Ecological Network Analysis to Predict the Impacts of Seawater Intrusion on an Estuarine Nitrogen Cycle
David Hines, Department of Biology and Marine Biology - UNC Wilmington
Microbial processes in estuarine sediments transform and remove biologically available forms of nitrogen from estuarine ecosystems. These nitrogen cycling processes can be coupled such that removal processes depend on transformation processes to supply a substantial portion of the reaction substrate. Seawater intrusion into the freshwater portions of estuaries results in changes to environmental chemistry that may alter the relationships among these biogeochemical processes. This work employs ecological network analysis to evaluate the potential impacts of seawater intrusion on the estuarine nitrogen cycle. We 1) present two comparative mass-balance network models for nitrogen budgets at an oligohaline and a polyhaline site in the Cape Fear River Estuary, NC, 2) estimate process coupling in each network, 3) evaluate the certainty of results using a Monte Carlo approach, and 4) use multiple hierarchical levels of analysis to further examine the results. This work presents a practical application of network analysis to highlight techniques that can be applied to a variety of systems.
September, 24 2013 | 12:30 - 2:00 | 230E Gross Hall