We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Does timber harvest influence the dynamics of marine-derived nutrients in Southeast Alaska streams?
- Authors
Levi, Peter S.; Tank, Jennifer L.; Tiegs, Scott D.; Rüegg, Janine; Chaloner, Dominic T.; Lamberti, Gary A.; Richardson, John
- Abstract
Streams often rely on nutrient subsidies, and variation in nutrient delivery may alter the ecosystem response. Pacific salmon ( Oncorhynchus spp.) provide marine-derived nutrients to their natal streams but also cause benthic disturbance, with the net effect determined by watershed and stream characteristics. To understand the factors contributing to variation in salmon-derived nutrients (SDN), we studied nutrient concentration and export in seven streams with varying physical characteristics due to timber harvest (e.g., channel complexity) over three years in Southeast Alaska, USA. Salmon increased concentrations and export of dissolved and particulate nitrogen, phosphorus, and carbon, but the magnitude of increase varied up to 41-fold among streams. The density of live salmon best predicted the increase in nutrient concentration and export, whereas the density of carcasses had a negligible effect. Nutrient export was predicted by transient storage before and after the salmon run. Streams in harvested watersheds with simplified channels had greater nutrient export than those in pristine watersheds with complex channels. However, enrichment from salmon overrode the effect of timber harvest on export during the run. Our study demonstrates that enrichment via SDN is short-lived and related to run size, whereas timber harvest and carcasses exert little influence on SDN dynamics.
- Subjects
SOUTHEAST Alaska; PACIFIC salmon; GROUNDFISHES; WATERSHEDS; NUTRIENT uptake; ANIMAL carcasses
- Publication
Canadian Journal of Fisheries & Aquatic Sciences, 2011, Vol 68, Issue 8, p1316
- ISSN
0706-652X
- Publication type
Article
- DOI
10.1139/f2011-067