This dataset provides vegetation characteristics collected at herbaceous and forested wetland sites within the Mississippi River Delta (MRD) floodplain across the Atchafalaya and Terrebonne basins in coastal Louisiana, USA. Data were collected during the 2015 Pre-Delta-X campaign.
At nine herbaceous wetland sites, a transect was established perpendicular to the wetland edge with replicate sample plots located at 50, 100, and 150 m to capture the range of vegetation structure, zonation, and composition. Aboveground biomass (AGB) was harvested inside the duplicate plots. At six forested wetland sites, duplicate circular plots were established inside the forest approximately 30 m from the wetland edge. All trees with a diameter at breast height > 2.5 cm were measured within each plot and identified to species. AGB was estimated using species-specific allometric equations. Measurements were used to generate marsh and forested wetland coverage and biomass in response to seasonality within both basins.
These data will be used by the Delta-X mission to calibrate remote sensing data (e.g., UAVSAR, AVIRIS-NG) and hydrodynamics and sediment transport models. Delta-X is a 5-year NASA Earth Venture Suborbital-3 mission to study the dynamic Mississippi River Delta in the United States. River deltas and their wetlands are drowning as a result of sea level rise and reduced sediment inputs. The mission will estimate which areas will survive and continue to grow, and which will be lost. It begins with airborne and in situ data acquisition and carries through data analysis, model integration, and validation to predict the extent and spatial patterns of future deltaic land loss or gain.
Other data from this mission can be found at the ORNL DAAC's Delta-X project page.
Data Citation: Castaneda, E., A.I. Christensen, M. Simard, A. Bevington, R. Twilley, and A. Mccall. 2020. Pre-Delta-X: Vegetation Species, Structure, Aboveground Biomass, MRD, LA, USA, 2015. ORNL DAAC, Oak Ridge, Tennessee, USA. https://doi.org/10.3334/ORNLDAAC/1805