Paul A Bukaveckas1. 1. Center for Environmental Studies, Department of Biology, Virginia Commonwealth University, Richmond, Virginia 23111, USA. pabukaveckas@vcu.edu
Abstract
Channel design is an important component of stream restoration, but little is known of the interplay between hydrogeomorphic features and ecosystem processes within designed channels. Water velocity, transient storage, and nutrient uptake were measured in channelized (prerestoration) and naturalized (postrestoration) reaches of a 1-km segment of Wilson Creek (KY) to assess the effects of restoration on mechanisms of nutrient retention. Stream restoration decreased flow velocity and reduced the downstream transport of nutrients. Median travel time was 50% greater in the restored channel due to lower reach-scale water velocity and the longer length of the meandering channel. Transient storage and the influence of transient storage on travel time were largely unaffected except in segments where backwater areas were created. First-order uptake rate coefficients for N and P were 30- and 3-fold higher (respectively) within the restored channel relative to its channelized state. Changes in uptake velocities were comparatively small, suggesting that restoration had little effect on biochemical demand. Results from this study suggest that channel naturalization enhances nutrient uptake by slowing water velocity. Solute injection experiments revealed differences in the functional properties of channelized, restored, and reference streams and provided a means for quantifying benefits associated with restoration of ecosystem services.
Channel design is an important component of stream restoration, but little is known of the interplay between hydrogeomorphic features and ecosystem processes within designed channels. Water velocity, tranpan>sienpan>t storage, anpan>d nutrienpan>t uptake were measured inpan> chanpan>nelized (prerestorationpan>) anpan>d naturalized (postrestorationpan>) reaches of a 1-km segmenpan>t of Wilsonpan> Creek (KY) to assess the effects of restorationpan> onpan> mechanpan>isms of nutrienpan>t retenpan>tionpan>. Stream restorationpan> decreased flow velocity anpan>d reduced the downpan>stream tranpan>sport of nutrienpan>ts. Medianpan> travel time was 50% greater inpan> the restored chanpan>nel due to lower reach-scale pan> class="Chemical">water velocity and the longer length of the meandering channel. Transient storage and the influence of transient storage on travel time were largely unaffected except in segments where backwater areas were created. First-order uptake rate coefficients for N and P were 30- and 3-fold higher (respectively) within the restored channel relative to its channelized state. Changes in uptake velocities were comparatively small, suggesting that restoration had little effect on biochemical demand. Results from this study suggest that channel naturalization enhances nutrient uptake by slowing water velocity. Solute injection experiments revealed differences in the functional properties of channelized, restored, and reference streams and provided a means for quantifying benefits associated with restoration of ecosystem services.
Authors: Sujay S Kaushal; Jenna E Reimer; Paul M Mayer; Ruth R Shatkay; Carly M Maas; William D Nguyen; Walter L Boger; Alexis M Yaculak; Thomas R Doody; Michael J Pennino; Nathan W Bailey; Joseph G Galella; Aaron Weingrad; Daniel C Collison; Kelsey L Wood; Shahan Haq; Tamara A Newcomer Johnson; Shuiwang Duan; Kenneth T Belt Journal: Freshw Sci Date: 2022-09-01 Impact factor: 2.353