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Freshwater ecosystems face ever increasing environmental and ecological challenges. Recognition of those challenges is not new—over 30 years ago, a series of workshops convened to develop a research agenda (The Freshwater Imperative) to address those challenges. It was recognized that a critical component of solving the problems that freshwater ecosystems face would require greater interdisciplinary collaboration. Here, we discuss the context for the "Revisiting the Freshwater Imperative" workshop and describe how a small‐workshop model can be used effectively to seed longer term collaborative partnerships in support of meeting the challenges freshwater ecosystems face. Some key recommendations include: (1) engage with participants prior to the workshop to maximize efficient use of time and prime divergence‐convergence thinking; (2) promote a bottom‐up participant driven structure; (2) develop an agenda with enough flexibility to accommodate participant driven changes (i.e., a "live" agenda); (3) utilize best practices for facilitating team science; and (4) provide coordinating structure for post‐workshop working group activities. [ABSTRACT FROM AUTHOR]

Processes that drive variability in catchment solute sourcing, transformation, and transport can be investigated using concentration–discharge (C–Q) relationships. These relationships reflect catchment and in-stream processes operating across nested temporal scales, incorporating both short and long-term patterns. Scientists can therefore leverage catchment-scale C–Q datasets to identify and distinguish among the underlying meteorological, biological, and geological processes that drive solute export patterns from catchments and influence the shape of their respective C–Q relationships. We have synthesized current knowledge regarding the influence of biological, geological, and meteorological processes on C–Q patterns for various solute types across diel to decadal time scales. We identify cross-scale linkages and tools researchers can use to explore these interactions across time scales. Finally, we identify knowledge gaps in our understanding of C–Q temporal dynamics as reflections of catchment and in-stream processes. We also lay the foundation for developing an integrated approach to investigate cross-scale linkages in the temporal dynamics of C–Q relationships, reflecting catchment biogeochemical processes and the effects of environmental change on water quality. [ABSTRACT FROM AUTHOR]

Diffuse nutrient runoff from agricultural fields can result in the eutrophication of downstream water bodies, highlighting a need for conservation efforts to reduce dissolved nitrogen (N) and phosphorus (P) loading to adjacent waterways. However, few studies explore how the impacts of field‐scale conservation manifest at the watershed scale. We explored how sources of streamflow and nutrients may influence the magnitude of the impact of conservation practices at a field versus watershed scale at the Shatto ditch watershed (SDW), where the planting of winter cover crops reduced field‐scale nitrate‐N (NO3−‐N) losses from subsurface tile drains by 69%–90%; yet watershed NO3−‐N export only decreased by 13%. To resolve this discrepancy, we used a water budget approach paired with water stable isotope (18O and 2H) analysis to determine the composition of streamflow across seasons, sampling five times from November 2018 to September 2019. While we hypothesized that watershed‐scale patterns in nutrient export were driven by direct groundwater upwelling, we found that this pathway only accounted for 43% of streamflow on average. We also developed a NO3−‐N mass balance for the watershed during our November 2018 sampling; results indicated groundwater upwelling contributed only ~1% of NO3−‐N export at the watershed outlet, while subsurface tile drains contributed the remaining 99%. Specifically, three large county tile drains (with an unknown drainage area and extent of conservation practice implementation) contributed ~69% of the watershed NO3−‐N export, obscuring the impacts of field‐scale conservation in SDW. Our study highlights the importance of cross‐scale analyses to accurately evaluate the effect of conservation given the interactions between sources of streamflow and nutrient loss at the watershed scale. [ABSTRACT FROM AUTHOR]

Article Impact Statement: We address solutions to current challenges in crowdsensing and provide a replicable framework for future groundwater monitoring studies. [ABSTRACT FROM AUTHOR]