Development of Coupled Physical and Ecological Models for Stress-Response Simulations of the Apalachicola Bay Regional Ecosystem

EPA Grant Number: R830880
Title: Development of Coupled Physical and Ecological Models for Stress-Response Simulations of the Apalachicola Bay Regional Ecosystem
Investigators: Huang, Wenrui , Gentile, John H. , Harwell, Mark A. , Hsieh, Ping , Johnson, Elijah , Milla, Katherine
Institution: Florida Agricultural and Mechanical University
EPA Project Officer: Hahn, Intaek
Project Period: July 10, 2003 through June 9, 2007
Project Amount: $749,691
RFA: Developing Regional-Scale Stressor-Response Models for Use in Environmental Decision-making (2002) RFA Text |  Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Ecosystems , Global Climate Change


The Apalachicola Bay ecosystem is a relatively pristine system on the coast of the Florida panhandle. The Bay and its surrounding waters have been recognized as a resource of state, federal, and international importance: it has been designated an Outstanding Florida Water, a State Aquatic Preserve, and an International Biosphere Reserve. It includes the Apalachicola Bay National Estuarine Research Reserve, and is adjacent to the St. Vincent National Wildlife Refuge. The Bay is the recipient of freshwater flows from the Apalachicola, Chattahoochee, and Flint River system (ACF), which drains over 60,000 km2 of Georgia, Alabama, and Florida. Of particular concern are the present and anticipated reductions below the historical freshwater flows because of urban (particularly Atlanta) and agricultural usage. Valued ecosystem components include oysters, recreational fisheries, salt marshes, and the associated aesthetic, endangered, and recreational species of birds, fish, and invertebrates. Stressors identified as affecting the Bay include changes in salinity, changes in sediment dynamics and turbidity, sea-level rise, nutrient inputs, tropical storms and hurricanes, and habitat alteration along the coast.


The present proposal is to develop a set of coupled physical and ecological models that can be used as assessment tools to evaluate the stress-responses of the Bay's ecological systems to all of these natural and anthropogenic stressors. An existing 3-dimensional hydrodynamic model implemented at Florida A&M University will be coupled with the EPA WASP 6 water quality model to simulate the current, transport, salinity, sediment, and nutrient regimes of the Bay. This physical model will also be coupled through a GIS framework to a series of ecological models to simulate ecological effects on the oyster population, the salt marsh grasses, and the landscape characteristics of the habitat mosaic distribution of the Bay's ecosystems. The utility of the salt barrens distribution will also be explored as an indicator of sea-level rise and salinity regime changes. Remote sensing will provide information for model calibration and stress responses.

Expected Results:

Following the ecological risk assessment framework, this coupled model system will be developed and tested against potential scenarios of multiple stressors to demonstrate the utility of the models as a tool for ecological risk assessment and risk management of the regional ecosystem. The proposed product will be available for direct support to the environmental decision-making process for the Apalachicola Bay and associated regional ecosystem.

Publications and Presentations:

Publications have been submitted on this project: View all 17 publications for this project

Journal Articles:

Journal Articles have been submitted on this project: View all 2 journal articles for this project

Supplemental Keywords:

multiple stressors, ecological risk assessment, regional assessments, ecological models, water quality, hydrodynamics, environmental decision-making., RFA, Scientific Discipline, Air, ECOSYSTEMS, Ecosystem Protection/Environmental Exposure & Risk, Ecosystem/Assessment/Indicators, climate change, Air Pollution Effects, Monitoring/Modeling, Environmental Monitoring, Regional/Scaling, Ecological Monitoring, Atmosphere, Ecological Indicators, anthropogenic stresses, aquatic ecosystem, risk assessment, stess response, ecosystem assessment, stressors, ecological modeling, modeling, regional environmental health, ecological assessment, hydrology, regional scale impacts, ecosystem indicators, regional scale, Apalachicola Bay, assessment methods, GIS, water quality, ecological risk, environmental stress, bay ecosystem, hydrologic modeling, ecological models, ecosystem stress, three dimensional model, modeling ecological risk, stressor response model, regional hydrologic modeling

Progress and Final Reports:

  • 2004 Progress Report
  • 2005
  • 2006 Progress Report
  • Final