Exploring Wetland Connectivity at the Catchment Scale: a Coupled Hydro-Chemical Modeling Approach

Abstract:

The hydrological and geochemical connections between geographically isolated wetland complexes and downstream waters can vary depending on multiple factors, such as landscape position, land-use, wetland size, and catchment and geological attributes. Understanding these connections are relevant to determining how best to conserve landscape scale water quality and storage functions that these wetlands provide. Since groundwater provides a physical and geochemical link between the wetland and the surrounding landscape, a basic unanswered question is how wetlands interact with adjacent (ground) waters. By understanding this interaction, and enumerating the relative role of the various controlling factors, we seek to upscale findings from individual wetlands to better assess interactions within and between wetland complexes and drainage features at the catchment scale. Such a perspective is relevant for understanding cumulative effects on downstream waters. We used a large scale distributed hydrological model to quantify groundwater-wetland interactions. Model results are compared to observation data of solute concentrations from wetland systems in North America and Canada, testing hypotheses regarding hydrological connectivity and local to regional trends in wetland geochemistry.