Record Details
Field | Value |
---|---|
Title | Determining in-channel (dead zone) transient storage by comparing solute transport in a bedrock channel–alluvial channel sequence, Oregon |
Names |
Gooseff, Michael N.
(creator) LaNier, Justin (creator) Haggerty, Roy (creator) Kokkeler, Kenneth (creator) |
Date Issued | 2005 (iso8601) |
Note | This is the publisher’s final pdf. The published article is copyrighted by the American Geophysical Union and can be found at: http://www.agu.org/journals/wr/. |
Abstract | Current stream tracer techniques do not allow separation of in-channel dead zone (e.g., eddies) and out-of-channel (hyporheic) transient storage, yet this separation is important to understanding stream biogeochemical processes. We characterize in-channel transient storage with a rhodamine WT solute tracer experiment in a 304 m cascade-pool-type bedrock reach with no hyporheic zone. We compare the solute breakthrough curve (BTC) from this reach to that of an adjacent 367 m alluvial reach with significant hyporheic exchange. In the bedrock reach, transient storage has an exponential residence time distribution with a mean residence time of 3.0 hours and a ratio of transient storage to stream volume of 0.14, demonstrating that at moderate discharge, bedrock in-channel storage zones provide a small volume of transient storage with substantial residence time. In the alluvial reach, though pools are similar in size to those in the bedrock reach, transient storage has a power law residence time distribution with a mean residence time of >100 hours (estimated at nearly 1200 hours) and a ratio of storage to stream volume of 105. Because the in-channel hydraulics of bedrock reaches are simpler than alluvial step-pool reaches, the bedrock results are probably a lower end-member with respect to volume and residence time, though they demonstrate that in-channel storage may be appreciable in some reaches. These results suggest that in-stream dead zone transient storage may be accurately simulated by exponential RTDs but that hyporheic exchange is better simulated with a power law RTD as a consequence of more complicated flow path and exchange dynamics. |
Genre | Article |
Topic | transient storage |
Identifier | Gooseff, M. N., J. LaNier, R. Haggerty, and K. Kokkeler (2005), Determining in-channel (dead zone) transient storage by comparing solute transport in a bedrock channel–alluvial channel sequence, Oregon, Water Resources Research, 41, W06014, doi:10.1029/2004WR003513. |