Hyporheic exchanges due to channel bed and width undulations
نویسندگان
چکیده
Riffle-pool sequences are fundamental, ubiquitous morphological features of alluvial rivers that thoroughly studied in general and commonly incorporated into river restoration projects. Most previous investigations on the effect riffle-pool hyporheic exchanges focused solely bed undulation, because is widely thought to be defining feature sequences. However, riffle- pool also have significant width undulations vital morphodynamics, yet relatively few studies exist such exchanges. Thus, this study based laboratory experiments numerical simulations, we investigate zone characteristics for various ratio amplitude amplitude. The variation exchange (i.e. flux residence time) different designs were assessed by creating prescribed topography synthetic valleys. results showed due pressure along undulations, upwelling downwelling patterns can observed only rivers, absence as undulation decreases, normalized (Q*HZ) increase median time (RT*) decreases. Also, simultaneous channel result higher Q*HZ especially when a located an expansion (aka “oversized” cross-section) riffle constriction (“nozzle”). Our suggest project artificially construct wide pools constricted riffles will achieve maximum RT*, though they not geomorphically self-sustainable.
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ژورنال
عنوان ژورنال: Advances in Water Resources
سال: 2021
ISSN: ['1872-9657', '0309-1708']
DOI: https://doi.org/10.1016/j.advwatres.2021.103857