Modeling Land Cover Change and Potential Management Impacts on Carbon Stocks of US Coastal Wetlands
Eric Jason Ward, USGS, eward@usgs.gov (Presenter)
Camille Stagg, USGS, staggc@usgs.gov
Colin Danile, APEX Resource Management Solutions, colin.daniel@apexrms.com
Rachel Sleeter, USGS, rsleeter@usgs.gov
Bronwyn Rayfield, APEX Resource Management Solutions, bronwyn.rayfield@apexrms.com
Lisamarie Windham-Myers, United States Geological Survey, lwindham@usgs.gov
Kevin D Kroeger, USGS, kkroeger@usgs.gov
Jinxun Liu, USGS, jxliu@usgs.gov
William Conner, Clemson University, wconner@clemson.edu
Richard Day, USGS, dayr@usgs.gov
Ken Krauss, USGS, kraussk@usgs.gov
Benjamin Sleeter, USGS, bsleeter@usgs.gov
Meagan Gonneea, USGS, mgonneea@usgs.gov
Karen Thorne, USGS, kthorne@usgs.gov
Kevin Buffington, USGS, kbuffington@usgs.gov
Scott Jones, USGS, sfjones@usgs.gov
Bergit Uhran, USGS, buhran@contractor.usgs.gov
Zhiliang Zhu, USGS, zzhu@usgs.gov
To support a comprehensive national-scale assessment of carbon sequestration and greenhouse gas (GHG) fluxes, the USGS has developed a model of carbon cycling in tidal wetlands of the contiguous US, including potential responses to future land cover change scenarios. The objectives of this model were to: 1) assess baseline carbon sequestration and GHG fluxes in coastal wetlands, 2) project scenarios of climate and land use impacts on carbon sequestration and GHG fluxes in coastal wetlands, and 3) assess the potential to increase carbon sequestration in coastal wetlands through management. We adapted the Land Use and Carbon Scenario Simulator (LUCAS) model, which was used in past assessments of terrestrial ecosystems, for use in tidal wetland ecosystems. LUCAS combines a state-and-transition simulation model (STSM) to predict land-change with a stock and flow model to simulate carbon dynamics, within a scenario-based framework to assess major controlling processes, characterize uncertainties, and develop future scenarios. As a test case, we calibrated LUCAS for the tidal wetlands of the Mississippi River Alluvial Plain (MRAP) in a spatially-referenced framework, using measurements of carbon pools and fluxes across 24 sites in the ecoregion, covering a range of salinity. We then assessed tidal zone carbon sequestration under current conditions with static land use and land cover (LULC) and with historic LULC changes from 1996-2010 across the ecoregion. Our results highlight that estimates of carbon sequestration in the tidal portion of the MRAP are extremely sensitive to assumptions about the fate of soil carbon when coastal wetlands transition to open water. We will further discuss how empirical distributions from calibration data can be used to estimate projection uncertainties using a stochastic Monte Carlo modeling approach and how this modeling platform will be extended from the test case ecoregion to tidal wetlands of all ecoregions in the contiguous US.
Poster: Poster_Ward_0_40_21.pdf
Recording: Video_Poster_Ward_0_40_21.mp4
Presentation Type: Poster
Session: Linkages among the Air-Land-Water Continuum