Modeling Linkage of Hydrology to Biogeochemistry

My project at SESYNC is part of a larger collaborative effort examining the effect of hydrologic connectivity on carbon export from headwater catchments on the eastern shore of Maryland. Previous field investigations have highlighted the role of upland wetlands and their connectivity to downstream waters as important drivers of both landscape hydrology and downstream water quality. To better understand these variables, our larger group is monitoring water quality with multiple high-temporal sensors, estimating greenhouse gas emissions through eddy covariance flux towers, and utilizing state of the art remote sensing products to characterize surface water hydrology. My contribution to this work includes the development of a wetland hydrology model, where we are integrating field based and remotely sensed measurements with process based modeling to characterize hydrologic connectivity of headwater catchments. Our modeling efforts are based on the concept of hydrologic capacitance, or the idea that surface water-groundwater interactions across groups of wetlands modulate surficial groundwater fluxes, mitigating both low and high stream flows. To examine this effect on the eastern shore of Maryland, we are developing a spatially explicit, process-based model that simulates surface-water groundwater fluxes of headwater catchments dominated by upland wetlands. In combination with our remote sensing and field based measurements, this tool will allow us to investigate the role of hydrologic modification (e.g., ditching) on both landscape hydrology and downstream carbon fluxes. The culmination of our larger group’s effort will lead to a better understanding of landscape processes, and ultimately, help guide policy and restoration practices in the Chesapeake Bay region.