Affiliation:
1. Department of Geosciences Colorado State University Fort Collins CO USA
2. School of Earth Sciences The Ohio State University Columbus OH USA
3. Hydrologic Science and Engineering Program Colorado School of Mines Golden CO USA
Abstract
AbstractLogjams in a stream create backwater conditions and locally force water to flow through the streambed, creating zones of transient storage within the surface and subsurface of a stream. We investigate the relative importance of logjam distribution density, logjam permeability, and discharge on transient storage in a simplified experimental channel. We use physical flume experiments in which we inject a salt tracer, monitor fluid conductivity breakthrough curves in surface water, and determine breakthrough‐curve skewness to characterize transient storage. We then develop a companion numerical model in HydroGeoSphere to reveal flow paths through the subsurface (or hyporheic zone) that contribute to some of the longest transient‐storage timescales. In both the flume experiments and numerical simulations, we observe backwater formation and an increase in hyporheic exchange at logjams. Observed complexities in transient storage behavior depend largely on surface water flow in the backwater zone. As expected, multiple successive logjams provide more pervasive hyporheic exchange by distributing the head drop at each jam, leading to distributed but shallow flow paths. Decreasing the permeability of a logjam or increasing the discharge both facilitate greater surface water storage and volumetric rate of hyporheic exchange. Understanding how logjam characteristics affect solute transport through both the channel and hyporheic zone has important management implications for rivers in forested, or historically forested, environments.
Funder
National Science Foundation
Publisher
American Geophysical Union (AGU)
Subject
Water Science and Technology
Reference108 articles.
1. Integrating engineered log jam technology into river rehabilitation;Abbe T.;Restoration of Puget Sound Rivers,2003
2. LARGE WOODY DEBRIS JAMS, CHANNEL HYDRAULICS AND HABITAT FORMATION IN LARGE RIVERS
3. Logjams as a driver of transient storage in a mountain stream
4. Patterns in stream longitudinal profiles and implications for hyporheic exchange flow at the H.J. Andrews Experimental Forest, Oregon, USA
5. Aquanty Inc. (2015).HydroGeoSphere. A three‐dimensional numerical model describing fully‐integrated subsurface and surface flow and solute transport[Software].Aquanty. Retrieved fromhttps://aquanty-artifacts-public.s3.amazonaws.com/hgs/hydrosphere_user.pdf?v=2
Cited by
4 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献