4. Discussion
Coupling hydrometric measurements such as stage with estimates of geochemical and microbial connectivity strength is useful for describing spatiotemporal patterns in connectivity at both target site specific and river-floodplain system scales. At the target site specific level, source-target stage relationships reveal patterns of hydrologic response to both shifting river flows and subsurface groundwater levels. While high water levels are associated with higher connectivity, source-target stage relationships are sensitive to both shifts in connectivity type and the site-level geomorphic controls on water level. However, these relationships do not necessarily contain information about the type of connectivity present (surface vs subsurface) without additional contextual information. For example, in our study both Pond-Con-01 and Pond-Iso demonstrated similar source-target stage relationships with Inflow throughout the hydrograph even though Pond-Iso likely had little to no surface connection with Inflow, whereas Pond-Con-01 did have surface connectivity. As such, source-target stage relationships did not reveal differences in surface connectivity between Pond-Con-01 or Pond-Iso and Inflow. However, our connectivity metrics derived from geochemical (σg) and microbial (σm) indicators did identify differences in connectivity between Pond-Con-01 and Pond-Iso and Inflow. Specifically, both σg and σm revealed low connectivity between Inflow and Pond-Iso but higher connectivity strength values between Inflow and Pond-Con-01 during high flows, both of which match our visual field observations of surface water connections. Accordingly, source-target stage relationships alone did not provide insight to functional connectivity defined by the observed influence of the source site on the target site, whereas geochemical and microbial indicators did. Therefore, we focus on the σg and σm connectivity strength metrics to describe spatial and temporal patterns of connectivity within the river-floodplain system.