An analysis of wetland productivity and biomass in Coastal Louisiana: Current base line data and knowledge gaps for the development of spatially explicit models for restoration and rehabilitation programs

Victor H Rivera-Monroy1, Courtney Elliton1, Jenneke Visser2, Siddhartha Narra3, Marc Simard4, Gregg Snedden5, Camille LaFosse Stagg5, Hongqing Wang6 and Edward Castañeda-Moya1, (1)Louisiana State University, School of the Coast and the Enivronment, Department of Oceanography and Coastal Sciences, Baton Rouge, LA, United States, (2)University of Louisiana at Lafayette, Lafayette, LA, United States, (3)Louisiana State University, Center for Energy Studies, Baton Rouge, LA, United States, (4)NASA Jet Propulsion Laboratory, Pasadena, CA, United States, (5)U.S. Geological Survey, National Wetlands Research Center, Lafayette, LA, United States, (6)U.S. Geological Survey, Wetland and Aquatic Research Center, Baton Rouge, LA, United States
Abstract:
Wetland above and below net primary productivity (NPP) and biomass (BM) are two critical ecosystem properties to evaluate vegetation successional trajectories in restoration and rehabilitation (R/R) programs. Enhancing sediment deposition and changes in salinity regimes are major environmental drivers that significantly determine vegetation establishment and species composition. In costal Louisiana, wetland restoration and rehabilitation (R/R)programs aim to slow down wetland loss and improve vegetation coverage by diverting freshwater and sediments from the Mississippi River into areas where wetlands loss rates are high. Although vegetation establishment and coverage are considered key performance measures (PMs) to evaluate R/R success, few studies have explicitly established NPP and BM targets due to the lack of long-term studies to analyze spatiotemporal patterns. To contribute to the development of vegetation PMs in restoration projects, we evaluated BM and NPP data and assessed statistical measures of central tendency and dispersion, field methodology, and number of studies per wetland class and species across coastal Louisiana from 1974-2014. Mean NPP ranged from 400 (±250) to 8500 (±500) gdw/m2/yr and showed significant differences among wetland types independently of salinity regime. Peak BM at the end of the growing season was distinct among wetlands communities dominated by grasses, particularly between freshwater (1200 g/m2 ± 300) and brackish/saline marshes (700 g/m2 ±250). Productivity studies have been focused on few species including Panicum virgatum, Scirpus americanus, Spartina patens, Juncus roemerianus, Distichlis spicata, Spartina alterniflora, Sagittaria falcate, Taxodium distichum, Nyssa aquatic, Acer rubrum. The BM/NPP analysis and database compilation will be used to inform the development and integration of functional performance measures in ecological models (statistical, dynamic and cellular automata) to forecast wetland R/R scenarios in coastal Louisiana.
Back to: Moving the Mississippi River Delta toward Long-Term Sustainability: Opportunities and Limitations II Posters