Earth Research Institute, University of California, Santa Barbara, California 93106, USA.
Ecology. 2011 Jun;92(6):1193-200. doi: 10.1890/10-1436.1.
Understanding the mechanisms that create spatial heterogeneity in species distributions is fundamental to ecology. For nearshore marine systems, most species have a pelagic larval stage where dispersal is strongly influenced by patterns of ocean circulation. Concomitantly, nearshore habitats and the local environment are also influenced by ocean circulation. Because of the shared dependence on the seascape, distinguishing the relative importance of the local environment from regional patterns of dispersal for community structure remains a challenge. Here, we quantify the "oceanographic distance" and "oceanographic asymmetry" between nearshore sites using ocean circulation modeling results. These novel metrics quantify spatial separation based on realistic patterns of ocean circulation, and we explore their explanatory power for intertidal and subtidal community similarity in the Southern California Bight. We find that these metrics show significant correspondence with patterns of community similarity and that their combined explanatory power exceeds that of the thermal structure of the domain. Our approach identifies the unique influence of ocean circulation on community structure and provides evidence for oceanographically mediated dispersal limitation in nearshore marine communities.
理解造成物种分布空间异质性的机制是生态学的基础。对于近岸海洋系统，大多数物种都有一个浮游幼体阶段，在这个阶段，扩散强烈受到海洋环流模式的影响。同时，近岸生境和当地环境也受到海洋环流的影响。由于共同依赖于海洋景观，区分本地环境与扩散的区域模式对群落结构的相对重要性仍然是一个挑战。在这里，我们使用海洋环流模型的结果来量化近岸站点之间的“海洋距离”和“海洋不对称性”。这些新的指标基于现实的海洋环流模式来量化空间分离，我们探索了它们在南加州湾潮间带和亚潮带群落相似性中的解释力。我们发现这些指标与群落相似性模式具有显著的对应关系，并且它们的综合解释力超过了域的热结构。我们的方法确定了海洋环流对群落结构的独特影响，并为近岸海洋群落中海洋介导的扩散限制提供了证据。
