Earth to Ocean Research Group, Department of Biological Sciences, Simon Fraser University, Burnaby, British Columbia, Canada.
Raincoast Conservation Foundation, P.O. Box 2429, Sidney, British Columbia, V8L 3Y3, Canada.
Ecology. 2020 Sep;101(9):e03060. doi: 10.1002/ecy.3060. Epub 2020 Aug 20.
Pacific salmon influence temperate terrestrial and freshwater ecosystems through the dispersal of marine-derived nutrients and ecosystem engineering of stream beds when spawning. They also support large fisheries, particularly along the west coast of North America. We provide a comprehensive synthesis of relationships between the densities of Pacific salmon and terrestrial and aquatic ecosystems, summarize the direction, shape, and magnitude of these relationships, and identify possible ecosystem-based management indicators and benchmarks. We found 31 studies that provided 172 relationships between salmon density (or salmon abundance) and species abundance, species diversity, food provisioning, individual growth, concentration of marine-derived isotopes, nutrient enhancement, phenology, and several other ecological responses. The most common published relationship was between salmon density and marine-derived isotopes (40%), whereas very few relationships quantified ecosystem-level responses (5%). Only 13% of all relationships tended to reach an asymptote (i.e., a saturating response) as salmon densities increased. The number of salmon killed by bears and the change in biomass of different stream invertebrate taxa between spawning and nonspawning seasons were relationships that usually reached saturation. Approximately 46% of all relationships were best described with linear or curved nonasymptotic models, indicating a lack of saturation. In contrast, 41% of data sets showed no relationship with salmon density or abundance, including many of the relationships with stream invertebrate and biofilm biomass density, marine-derived isotope concentrations, or vegetation density. Bears required the highest densities of salmon to reach their maximum observed food consumption (i.e., 9.2 kg/m to reach the 90% threshold of the relationship's asymptote), followed by freshwater fish abundance (90% threshold = 7.3 kg/m of salmon). Although the effects of salmon density on ecosystems are highly varied, it appears that several of these relationships, such as bear food consumption, could be used to develop indicators and benchmarks for ecosystem-based fisheries management.
太平洋鲑鱼在产卵时通过散布海洋衍生的养分和对河床进行生态系统工程，影响着温带陆地和淡水生态系统。它们还支撑着大型渔业，特别是在北美洲西海岸。我们综合了太平洋鲑鱼的密度与陆地和水生生态系统之间的关系，总结了这些关系的方向、形状和大小，并确定了可能的基于生态系统的渔业管理指标和基准。我们发现了 31 项研究，提供了 172 种鲑鱼密度（或鲑鱼丰度）与物种丰度、物种多样性、食物供应、个体生长、海洋衍生同位素浓度、养分增强、物候和其他几种生态响应之间的关系。最常见的发表关系是鲑鱼密度与海洋衍生同位素之间的关系（40%），而很少有研究量化生态系统水平的响应（5%）。只有 13%的关系随着鲑鱼密度的增加而趋于渐近（即饱和响应）。熊杀死的鲑鱼数量和产卵季节与非产卵季节之间不同溪流无脊椎动物类群的生物量变化是通常达到饱和的关系。大约 46%的关系最好用线性或非线性非渐近模型来描述，表明没有饱和。相比之下，41%的数据组与鲑鱼密度或丰度没有关系，包括许多与溪流无脊椎动物和生物膜生物量密度、海洋衍生同位素浓度或植被密度的关系。熊需要最高密度的鲑鱼才能达到其最大观察到的食物消耗量（即 9.2kg/m，达到关系渐近线的 90%阈值），其次是淡水鱼类丰度（90%阈值= 7.3kg/m 的鲑鱼）。尽管鲑鱼密度对生态系统的影响是多种多样的，但似乎这些关系中的一些，如熊的食物消耗，可以用于制定基于生态系统的渔业管理指标和基准。
