Tidal wetland Gross Primary Production across the continental United States, 2000-2018

Rusty A Feagin1, Inke Forbrich2, Thomas Huff3, Jordan G Barr4, Jesus Ruiz-Plancarte5, Jose D Fuentes6, Raymond Najjar7, Rodrigo Vargas8, Alma Vazquez Lule8, Lisamarie Windham-Myers9, Kevin D Kroeger10, Eric J Ward11, Georgianne W Moore12, Monique Y Leclerc13, Ken Krauss14, Camille LaFosse Stagg15, Merryl Alber16, Sara H Knox17, Karina V Schafer18, Thomas S S Bianchi19, Jack Hutchings20, Hafsah B. Nahrawi13, Asko Noormets21, Bhaskar Mitra22, Aline Jaimes23, Audra Hinson24, Brian A Bergamaschi25 and John S King26, (1)Texas A&M University College Station, Ecology and Conservation Biology, and Ocean Engineering, College Station, TX, United States, (2)University of Toledo, Department of Environmental Sciences, Toledo, OH, United States, (3)Texas A&M University College Station, Ecosystem Science and Management, College Station, United States, (4)Elder Research, Inc., Charlottesville, VA, United States, (5)Pennsylvania State University Main Campus, University Park, United States, (6)Penn State University, University Park, United States, (7)The Pennsylvania State University, Meteorology and Atmospheric Science, University Park, United States, (8)University of Delaware, Plant and Soil Sciences, Newark, DE, United States, (9)USGS - National Research Program, Menlo Park, United States, (10)USGS, Woods Hole, United States, (11)U.S. Geological Survey, Wetland and Aquatic Research Center, Lafayette, LA, United States, (12)Georgia Southern University, Department of Biology, Statesboro, GA, United States, (13)University of Georgia, Griffin, United States, (14)Wetland and Aquatic Research Center, U.S. Geological Survey, Biology Department, Lafayette, United States, (15)U.S. Geological Survey, Wetland and Aquatic Research Center, Lafayette, United States, (16)University of Georgia, Marine Sciences, Athens, GA, United States, (17)McGill University, Geography, Montreal, QC, Canada, (18)Rutgers University Newark, Department of Earth and Environmental Sciences, Newark, United States, (19)University of Florida, Department of Geological Sciences, Gainesville, United States, (20)Washington University in St Louis, Earth, Environmental, and Planetary Sciences, St. Louis, United States, (21)Texas A&M University, Department of Ecology and Conservation Biology, College Station, United States, (22)Texas A&M University, Department of Ecosystem Science and Management, Texas, TX, United States, (23)Texas A&M University, College Station, TX, United States, (24)Texas A & M University, College Station, TX, United States, (25)USGS California Water Science Center Sacramento, Sacramento, United States, (26)North Carolina State University, Department of Forestry and Environmental Resources, Raleigh, United States
Abstract:
Our overall objective was to model and summarize tidal wetland gross primary production (GPP) for multiple types of wetlands across the continental United States (CONUS) at 16-day intervals across the years 2000-2018. To accomplish this task, we created the Blue Carbon (BC) model, which combined tidal wetland cover and eddy covariance (EC) tower data into a single Bayesian framework, and used a super computer network and remote sensing imagery (MODIS EVI) to model GPP in a spatially-explicit context. We found a strong fit between the BC model and EC data from ten different towers (r2=0.83, p<0.001, RMSE=1.22 g C/m2/day, average error was 7% with a mean bias of nearly zero). When compared with NASA’s MOD17 GPP product, a generalized terrestrial algorithm, the BC model reduced error by approximately half (MOD17 had r2=0.45, p<0.001, RMSE of 3.38 g C/m2/day, average error of 15%). The BC model also included mixed pixels, which comprised approximately 23.1% of CONUS tidal wetland GPP. Results showed that across CONUS between 2000 and 2018, the average daily GPP per m2 was 5.27 ± 0.13 g C/m2/day. The total annual GPP for the CONUS was 47.09 ± 1.20 Tg C/yr. GPP for the Gulf Coast was nearly double that of the Atlantic and Pacific Coasts combined. Louisiana alone accounted for 19.21 ± 0.73 Tg C/yr, with its Atchafalaya/Vermillion Bay basin at 5.07 ± 0.20 Tg C/yr. The BC model provides a robust platform for exploring GPP trends and responses in a detailed manner. Future uses of the model will be discussed.