Browsing by Author "Zarnetske, Jay P."

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    Co-located contemporaneous mapping of morphological, hydrological, chemical, and biological conditions in a 5th-order mountain stream network, Oregon, USA
    Ward, Adam S.; Zarnetske, Jay P.; Baranov, Viktor; Blaen, Phillip J.; Brekenfeld, Nicolai; Chu, Rosalie; Derelle, Romain; Drummond, Jennifer D.; Fleckenstein, Jan H.; Garayburu-Caruso, Vanessa; Graham, Emily B.; Hannah, David; Harman, Ciaran J.; Herzog, Skuyler; Hixson, Jase; Knapp, Julia L. A.; Krause, Stefan; Kurz, Marie J.; Lewandowski, Joerg; Li, Angang; Marti, Eugenia; Miller, Melinda C.; Milner, Alexander M.; Neil, Kerry; Orsini, Luisa; Packman, Aaron I.; Plont, Stephen; Renteria, Lupita; Roche, Kevin; Royer, Todd; Schmadel, Noah M.; Segura, Catalina; Stegen, James; Toyoda, Jason; Wells, Jacqueline; Wisnoski, Nathan I.; Wondzell, Steven M. (2019-10-22)
    A comprehensive set of measurements and calculated metrics describing physical, chemical, and biological conditions in the river corridor is presented. These data were collected in a catchment-wide, synoptic campaign in the H. J. Andrews Experimental Forest (Cascade Mountains, Oregon, USA) in summer 2016 during low-discharge conditions. Extensive characterization of 62 sites including surface water, hyporheic water, and streambed sediment was conducted spanning 1st- through 5th-order reaches in the river network. The objective of the sample design and data acquisition was to generate a novel data set to support scaling of river corridor processes across varying flows and morphologic forms present in a river network. The data are available at https://doi.org/10.4211/hs.f4484e0703f743c696c2e1f209abb842 (Ward, 2019).
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    Solute Transport and Transformation in an Intermittent, Headwater Mountain Stream with Diurnal Discharge Fluctuations
    Ward, Adam S.; Kurz, Marie J.; Schmadel, Noah M.; Knapp, Julia L. A.; Blaen, Phillip J.; Harman, Ciaran J.; Drummond, Jennifer D.; Hannah, David M.; Krause, Stefan; Li, Angang; Marti, Eugenia; Milner, Alexander M.; Miller, Melinda C.; Neil, Kerry; Plont, Stephen; Packman, Aaron I.; Wisnoski, Nathan I.; Wondzell, Steven M.; Zarnetske, Jay P. (MDPI, 2019-10-23)
    Time-variable discharge is known to control both transport and transformation of solutes in the river corridor. Still, few studies consider the interactions of transport and transformation together. Here, we consider how diurnal discharge fluctuations in an intermittent, headwater stream control reach-scale solute transport and transformation as measured with conservative and reactive tracers during a period of no precipitation. One common conceptual model is that extended contact times with hyporheic zones during low discharge conditions allows for increased transformation of reactive solutes. Instead, we found tracer timescales within the reach were related to discharge, described by a single discharge-variable StorAge Selection function. We found that Resazurin to Resorufin (Raz-to-Rru) transformation is static in time, and apparent differences in reactive tracer were due to interactions with different ages of storage, not with time-variable reactivity. Overall we found reactivity was highest in youngest storage locations, with minimal Raz-to-Rru conversion in waters older than about 20 h of storage in our study reach. Therefore, not all storage in the study reach has the same potential biogeochemical function and increasing residence time of solute storage does not necessarily increase reaction potential of that solute, contrary to prevailing expectations.
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    Spatial and temporal variation in river corridor exchange across a 5th-order mountain stream network
    Ward, Adam S.; Wondzell, Steven M.; Schmadel, Noah M.; Herzog, Skuyler; Zarnetske, Jay P.; Baranov, Viktor; Blaen, Phillip J.; Brekenfeld, Nicolai; Chu, Rosalie; Derelle, Romain; Drummond, Jennifer D.; Fleckenstein, Jan H.; Garayburu-Caruso, Vanessa; Graham, Emily B.; Hannah, David; Harman, Ciaran J.; Hixson, Jase; Knapp, Julia L. A.; Krause, Stefan; Kurz, Marie J.; Lewandowski, Joerg; Li, Angang; Marti, Eugenia; Miller, Melinda C.; Milner, Alexander M.; Neil, Kerry; Orsini, Luisa; Packman, Aaron I.; Plont, Stephen; Renteria, Lupita; Roche, Kevin; Royer, Todd; Segura, Catalina; Stegen, James; Toyoda, Jason; Wells, Jacqueline; Wisnoski, Nathan I. (2019-12-20)
    Although most field and modeling studies of river corridor exchange have been conducted at scales ranging from tens to hundreds of meters, results of these studies are used to predict their ecological and hydrological influences at the scale of river networks. Further complicating prediction, exchanges are expected to vary with hydrologic forcing and the local geomorphic setting. While we desire predictive power, we lack a complete spatiotemporal relationship relating discharge to the variation in geologic setting and hydrologic forcing that is expected across a river basin. Indeed, the conceptual model of Wondzell (2011) predicts systematic variation in river corridor exchange as a function of (1) variation in baseflow over time at a fixed location, (2) variation in discharge with location in the river network, and (3) local geomorphic setting. To test this conceptual model we conducted more than 60 solute tracer studies including a synoptic campaign in the 5th-order river network of the H. J. Andrews Experimental Forest (Oregon, USA) and replicate-intime experiments in four watersheds. We interpret the data using a series of metrics describing river corridor exchange and solute transport, testing for consistent direction and magnitude of relationships relating these metrics to discharge and local geomorphic setting. We confirmed systematic decrease in river corridor exchange space through the river networks, from headwaters to the larger main stem. However, we did not find systematic variation with changes in discharge through time or with local geomorphic setting. While interpretation of our results is complicated by problems with the analytical methods, the results are sufficiently robust for us to conclude that space-for-time and time-for-space substitutions are not appropriate in our study system. Finally, we suggest two strategies that will improve the interpretability of tracer test results and help the hyporheic community develop robust datasets that will enable comparisons across multiple sites and/or discharge conditions.