Interhemispheric comparison of recruitment to intertidal communities: pattern persistence and scales of variation.
Interhemispheric comparison of recruitment to intertidal communities: pattern persistence and scales of variation.
复制标题
潮间带群落招募的半球间比较：模式持续性和变化规模。
作者：
S. Navarrete;B. Broitman;B. Menge
招募变异可能是种群和群落波动的主要来源，因此很难概括结果。确定变化的尺度以及个体供应的空间模式是否随着时间的推移而持续，可以深入了解空间的一般性以及保护和元生态模型的应用。我们使用长达八年的潮间带贻贝（贻贝属，Perumytilus purpuratus，Semimytilus algosus，Brachidontes granulata）和藤壶（Balanus glandula，Chthalus dalli，Jehlius cirratus，Notochthalus scabrosus），分布在俄勒冈州-加州州北部（OR-NCA，45.47-39.43度N）和智利中部（CC，29.5-34.65度S）海岸沿着> 900 km的地点。我们评估了四个一般性的“零”假设：尽管这些类群具有不同的亲缘关系和巨大的空间分离，但它们相似的生活史策略和环境设置导致了相似的招募模式（1）半球之间，（2）时间上，（3）空间上，（4）更大和更小的空间尺度。假设1被拒绝：沿着OR-NCA海岸，招聘率高出两到三个数量级，季节性模式一般更强，更连贯的空间和时间比沿着CC。然而，令人惊讶的是，进一步的分析显示，所有物种在时间和空间上都是一致的，支持假设2和3。时间去相关尺度为1-3个月，和特征的空间尺度的招聘约为250公里。相反的假设4，在两个半球的生态优势物种，招聘是非常持久的较大的中尺度（公里），但在较小的微尺度（米）是高度随机的。在不同物种中，大规模的招募变异增加与持久性增加呈正相关。我们的结果有几个影响。虽然这两个地区跨越不同的纬度范围，这些模式背后的潜在强迫过程包括类似的大尺度气候和地形锁定水文特征，如上升流。此外，大多数物种在中尺度的补充模式在空间上的持久性支持了海洋保护区可以成为有力的养护和管理工具的观点。最后，持久的，但对比的空间格局之间的竞争物种的招聘表明，最近的metacompatibility模型可能提供有用的表示参与物种共存的机制。
Recruitment variation can be a major source of fluctuation in populations and communities, making it difficult to generalize results. Determining the scales of variation and whether spatial patterns in the supply of individuals are persistent over time can provide insight into spatial generality and the application of conservation and metacommunity models. We examined these issues using eight-year-long data sets of monthly recruitment of intertidal mussels (Mytilus spp., Perumytilus purpuratus, Semimytilus algosus, Brachidontes granulata) and barnacles (Balanus glandula, Chthamalus dalli, Jehlius cirratus, Notochthamalus scabrosus) at sites spanning > 900 km along the coasts of Oregon-northern California (OR-NCA, 45.47-39.43 degrees N) and central Chile (CC, 29.5-34.65 degrees S). We evaluated four general "null" hypotheses: that despite different phylogenies and great spatial separation of these taxa, their similar life history strategies and environmental settings lead to similar patterns of recruitment (1) between hemispheres, (2) in time, (3) in space, and (4) at larger and smaller spatial scales. Hypothesis 1 was rejected: along the OR-NCA coast, rates of recruitment were between two and three orders of magnitude higher, and patterns of seasonality were generally stronger and more coherent across space and time than along CC. Surprisingly, however, further analysis revealed regularities in both time and space for all species, supporting hypotheses 2 and 3. Temporal decorrelation scales were 1-3 months, and characteristic spatial scales of recruitment were approximately 250 km. Contrary to hypothesis 4, for the ecologically dominant species in both hemispheres, recruitment was remarkably persistent at larger mesoscales (kilometers) but was highly stochastic at smaller microscales (meters). Across species, increased recruitment variation at large scales was positively associated with increased persistence. Our results have several implications. Although the two regions span distinct latitudinal ranges, potential forcing processes behind these patterns include similar large-scale climates and topographically locked hydrographic features, such as upwelling. Further, spatial persistence of the recruitment patterns of most species at the mesoscale supports the view that marine protected areas can be powerful conservation and management tools. Finally, persistent and yet contrasting spatial patterns of recruitment among competing species suggest that recent metacommunity models might provide useful representations of the mechanisms involved in species coexistence.