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Wildfire substantially alters aquatic ecosystems by inducing moderate to catastrophic physical and chemical changes. However, the relations of environmental and watershed variables that drive those effects are complex. We present a Driver‐Factor‐Stressor‐Effect (DFSE) conceptual framework to assess the current state of the science related to post‐wildfire water‐quality. We reviewed 64 peer‐reviewed papers using the DFSE framework to identify drivers, factors, stressors, and effects associated with each study. A total of five drivers were identified and ranked according to their frequency of occurrence in the literature: atmospheric processes > fire characteristics > ecologic processes and characteristics > land surface characteristics > soil characteristics. Commonly reported stressors include increased nutrients, runoff, and sediment transport. Furthermore, although several different factors have been used at least once to explain water‐quality effects, relatively few factors outside of precipitation and fire characteristics are frequently studied. We identified several gaps indicating the need for long‐term monitoring, multi‐factor studies, consideration of organic contaminants, consideration of groundwater, and inclusion of soil characteristics. This assessment expands on other reviews and meta‐analyses by exploring causal linkages between influential variables and overall effects in post‐wildfire watersheds. Information gathered from our assessment and the framework itself can be used to inform future monitoring plans and as a guide for modeling efforts focused on better understanding specific processes or to mitigate potential risks of post‐wildfire water quality. Plain Language Summary: Wildfires impact the hydrology and water quality of surface waters that drain burned areas. However, the environmental and watershed factors that drive post‐wildfire water quality are not well understood. We conducted a scoping review of peer‐reviewed publications to assess the current state of the science and identify knowledge gaps. Using the data gathered from the review, we developed a conceptual framework to identify factors that most frequently explain post‐wildfire impacts, the resulting stressors (i.e., changes in the system), and the effects associated with the observed stressors. Precipitation and burn severity are most frequently related to post‐wildfire impacts. Factors such as soil characteristics are studied relatively infrequently. Effects include impaired water quality, increased drinking water treatment, and increased streamflow. Our analysis identified several gaps that can be filled by long‐term monitoring, conducting studies in geographic regions affected by wildfire but where little data exists, expanding current observations to better understand shifts in baseflow contributions, and expanding chemical analyses to include organic contaminants. Key Points: Precipitation and burn severity are studied more often than soil and land characteristics to explain post‐wildfire water qualityIncreased streamflow and impaired water quality are the most documented effects of wildfire, though other effects can be importantKnowledge gaps include long‐term monitoring, multi‐factor studies, and consideration of groundwater and organic contaminants [ABSTRACT FROM AUTHOR]

A commercially available electromagnetic flowmeter is attached to a seepage cylinder to create an electromagnetic seepage meter (ESM) for automating measurement of fluxes across the sediment/water interface between ground water and surface water. The ESM is evaluated through its application at two lakes in New England, one where water seeps into the lake and one where water seeps out of the lake. The electromagnetic flowmeter replaces the seepage-meter bag and provides a continuous series of measurements from which temporal seepage processes can be investigated. It provides flow measurements over a range of three orders of magnitude, and contains no protruding components or moving parts. The ESM was used to evaluate duration of seepage disturbance following meter installation and indicated natural seepage rates resumed approximately one hour following meter insertion in a sandy lakebed. Lakebed seepage also varied considerably in response to lakebed disturbances, near-shore waves, and rain-falls, indicating hydrologic processes are occurring in shallow lakebed settings at time scales that have largely gone unobserved., Introduction The quantification of fluid exchange between lakes and ground water has become increasingly important as the understanding of the physical, chemical, and biological linkages between lake water and ground [...]

Ground water exchange affects the ecology of surface water by sustaining stream base flow and moderating water-level fluctuations of ground water-fed lakes. It also provides stable-temperature habitats and supplies nutrients and inorganic ions. Ground water input of nutrients can even determine the trophic status of lakes and the distribution of macrophytes. In streams the mixing of ground water and surface water in shallow channel and bankside sediments creates a unique environment called the hyporheic zone, an important component of the lotic ecosystem. Localized areas of high ground water discharge in streams provide thermal refugia for fish. Ground water also provides moisture to riparian vegetation, which in turn supplies organic matter to streams and enhances bank resistance to erosion. As hydrologists and ecologists interact to understand the impact of ground water on aquatic ecology, a new research field called 'ecohydrology' is emerging., Editor's note: This paper is reprinted with slight modification from the Japanese Journal of Groundwater Hydrology 43, 327-341, published by the Japanese Association of Groundwater Hydrology, 2001. Introduction Surface water [...]