Pacific Salmon, Nutrients, and the Dynamics of Freshwater and Riparian Ecosystems

• Published in: Ecosystems (New York) Vol. 5; no. 4; pp. 399 - 417
• Main Authors: Naiman, Robert J., Bilby, Robert E., Schindler, Daniel E., Helfield, James M.
• Format: Journal Article
• Language: English
• Published: New York, NY Springer-Verlag 01.06.2002; Springer; Springer Nature B.V
• Subjects: Animal and plant ecology; Animal populations; Animal, plant and microbial ecology; Applied ecology; Aquatic ecosystems; Aquatic habitats; Biological and medical sciences; Coastal zone; Ecosystem management; Ecotoxicology, biological effects of pollution; Fish populations; Fresh water; Fresh water ecosystems; Freshwater ecosystems; Freshwater environments; Freshwater fishes; Fundamental and applied biological sciences. Psychology; Lakes; Lentic systems; Marine and brackish environment; Marine ecosystems; Marine fishes; Minireview; Natural resource management; Nutrients; Oligotrophic lakes; Predators; Riparian ecology; Riparian vegetation; Salmon; Spawning; Streams; Synecology; Watersheds; North America; America; Salmonidae; Isotopic analysis; Energy flow; Life history; Mortality; Environmental factor; Biogeochemical cycle; Carcass; Body composition; Biological productivity; Breeding site; Freshwater environment; Marine environment; Vertebrata; Migratory; Pisces; Lakes; Nutrient; Stream
• ISSN: 1432-9840; 1435-0629
• DOI: 10.1007/s10021-001-0083-3

Pacific salmon (Oncorhynchus spp.) accumulate substantial nutrients in their bodies as they grow to adulthood at sea. These nutrients are carried to predominantly oligotrophic lakes and streams, where they are released during and after spawning. Research over more than 3 decades has shown that the annual deposition of salmon-borne marine-derived nutrients (MD-nutrients) is important for the productivity of freshwater communities throughout the Pacific coastal region. However, the pathways and mechanisms for MD-nutrient transfer and accumulation in freshwater and riparian ecosystems remain virtually unexplored, consequently, there are many uncertainties in this area. This article addresses three related topics. First, we summarize recent advances in our understanding of the linkages among MD-nutrients, freshwater (including riparian) ecosystems, and community dynamics by addressing the importance of MD-nutrients to lakes and streams and by then reviewing large-scale and long-term processes in the atmosphere and ocean that govern variability in salmon populations. Second, we evaluate the validity of the discoveries and their implications for active ecosystem management, noting areas where extrapolation from these results still requires great caution. Finally, we outline five key research issues where additional discoveries could greatly augment our understanding of the processes shaping the structure and dynamics of salmon populations and the characteristics of their freshwater habitat and associated riparian zones. Collectively, the data suggest that the freshwater portion of the salmon production system is intimately linked to the ocean. Moreover, for the system to be sustainable, a holistic approach to management will be required. This holistic approach will need to treat climate cycles, salmon, riparian vegetation, predators, and MD-nutrient flowpaths and feedbacks as an integrated system.