Applying Ecological Succession Theory to Evaluate Wetland Restoration in Urbanizing Coastal WatershedsEPA Grant Number: R826111
Title: Applying Ecological Succession Theory to Evaluate Wetland Restoration in Urbanizing Coastal Watersheds
Investigators: Craft, C. B. , Broome, S. W. , Megonigal, J. P. , Stevenson, R. Jan
Institution: Indiana University - Bloomington
EPA Project Officer: Hahn, Intaek
Project Period: June 1, 1998 through May 31, 2001 (Extended to May 30, 2002)
Project Amount: $534,239
RFA: Ecosystem Restoration (1997) RFA Text | Recipients Lists
Research Category: Ecological Indicators/Assessment/Restoration , Hazardous Waste/Remediation , Land and Waste Management , Ecosystems
Wetland restoration increasingly is used to mitigate for loss of habitat and ecosystem function caused by human activities. Coastal and estuarine watersheds support an enormous tourist and sportfishing industry and are an important commercial fisheries resource for the mid-atlantic and southeastern US region. A large part of the economy of this region depends directly (habitat) and indirectly (water quality) on the maintenance of abundant and healthy wetland resources. However, urbanization and concurrent loss of existing wetlands may lead to degradation and loss of the natural resource and the environmental quality that support the local and regional economies.
Objectives:The development of wetland structure and function will be investigated using restored estuarine marshes in North Carolina and Virginia to answer three key questions concerning development of community structure and ecosystem processes over time on restored coastal wetlands: (1) What timescales are required to achieve full or complete restoration of the different attributes of wetland structure and function? (2) What indicators can be used to determine whether full or complete restoration of wetland structure and function has been achieved? (3) How can successional theory be used to predict the rate of development of wetland structure and function on ecologically similar restored wetlands?
Four attributes of wetland structure and function, (1) primary (macrophyte, algae) and secondary (microbial, benthic invertebrates) productivity, (2) habitat/species diversity, (3) biogeochemical processes (organic carbon accumulation, decomposition, trace gas emissions) and (4) water quality improvement (sediment, N, P retention; denitrification) will be measured in eight different age (1-30 yr) restored and paired natural reference salt marshes in urbanizing watersheds of North Carolina. The information from this study and from previous published studies at these sites will be used to develop timelines that describe the rate of development of the different ecological attributes over time. Indicators of wetland structure and function (macro- and soil organic matter content and quality, particle size) will be evaluated for their ability to predict the degree of full or complete restoration of wetland community structure and ecosystem processes on these and other ecologically similar restored wetlands. The validity of our timelines, indicators and predictions based on ecological succession theory will be tested by measuring primary and secondary productivity, habitat/species diversity, biogeochemical processes and water quality improvement in ecologically similar restored tidal freshwater marshes in urbanizing areas of the Chesapeake Bay, near Washington DC.
The information from this project will be useful for (1) determining the rate at which different ecological attributes develop on restored coastal wetlands so that chronological targets for specific indicators can be established for these ecosystems, (2) evaluating indicators that can be used to assess the degree of full or complete restoration of wetland structure and function on these and other ecologically similar restored sites and (3) developing timelines based on succession theory that can be applied to predict the rate at which ecosystem structure and function develop on restored estuarine wetlands throughout the mid-atlantic and southeastern coasts.