PARSING HYDROLOGIC AND BIOGEOCHEMICAL CONNECTIVITY IN A COMPLEX MONTANE FLOODPLAIN
In undisturbed mountain valleys, interactions between streams and riparian areas generate physically complex floodplains with substantial variation in the magnitude, timing and directionally of hydrologic connectivity. These lateral exchanges of water and solutes regulate biogeochemical functioning within floodplain habitats and alter downstream solute concentrations. Recent advances have suggested that time series analyses of high frequency sensors measuring water levels and water chemistry can improve our ability to quantify variable connectivity states within a landscape. Here, we propose that concurrent analysis of both water level and chemical signals not only improves quantification of binary connectivity metrics (eg: connected/disconnected) but also helps identify the form of lateral hydrologic connectivity (surface/subsurface) in systems where connectivity states can shift as a function of both seasonal hydrologic regimes and dynamic geomorphic processes. We further explore how differing physio-chemical time series (temperature, colored dissolved organic matter, conductivity and dissolved oxygen) within floodplain habitats are impacted by these shifts in connectivity to the stream. Disentangling connectivity information contained within these different chemical signals is crucial to the establishment of a robust quantitative connectivity framework that can account for both hydrologic and biogeochemical dynamics.
Tim Covino (Co-Presenter/Co-Author), Colorado State University, Tim.Covino@ColoState.EDU;
Alexander Brooks (Primary Presenter/Author), Colorado State University, firstname.lastname@example.org;