| ID |
2644 |
| Citation |
Rex, J.F., Petticrew, E.L., Albers, S.J. and Williams, N.D. (2014). The influence of Pacific salmon decay products on near-field stream bed sediment and organic matter dynamics: A flume simulation. Earth Surface Process and Landforms. 39:1378-1385. |
| Organization |
University of Northern British Columbia; Ministry of Forests, Lands, and Natural Resource Operations; URS Infrastructure and Environment UK Ltd |
| URL |
http://www.unbc.ca/sites/default/files/sections/quesnel-river-research-centre/rex2014-ps15.pdf |
| Abstract/Description or Keywords |
Pacific salmon are biogeomorphic agents shown to induce positive feedbacks on their natal watersheds. However, the literature documenting their ecological effects on in-stream natal environments is more divisive. The disturbance salmon create during redd construction has the potential to reduce stream productivity. The pulse of salmon organic matter (SOM) and marine derived nutrients (MDNs) released during carcass decay has been reported as either stimulating in-stream productivity or having no local effect. To evaluate the ecological costs and benefits of salmon spawning events, MDN delivery and storage processes need to be identified and quantified. A simulation was conducted in three flow-through flumes (2m_ 2m_ 30m) over a 33-day period (consisting of 15 baseline, four MDN exposure, and 14 post-exposure days) to assess near-field sediment and organic matter dynamics during active and post-spawn simulations. The objective of the study was to measure changes in the amounts and particle sizes of suspended and gravel-stored fine sediment, in order to elucidate the process and significance of SOM recruitment to the gravel bed via sedimentation. Gravel beds in all flumes were enriched with SOM following treatments but the response was highest in the active spawn simulation. The more effective delivery in the active spawn simulation was attributed to its higher inorganic sediment concentration, which is known to enhance floc formation. Although the active spawn simulation delivered more SOM to the gravel bed, the post-spawn phase may be equally important to natural streams because its decay phase is longer than the active spawn and consequently can provide SOM to the streambed as long as carcasses remain in-stream. The delivery, and potential retention, of SOM to spawning streambeds and the intergravel environment may be particularly important for interior streams, which experience low flow conditions during the spawning phase and accordingly have the potential for hyporheic nutrient recruitment and storage. Pacific salmon; marine-derived nutrients; organic matter; fine sediment; flocculation; flume simulation |
| Information Type |
Article |
| Regional Watershed |
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| Sub-watershed if known |
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| Aquifer # |
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| Comments |
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| Project status |
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| Contact Name |
John F. Rex |
| Contact Email |
[email protected] |
