The Role of Biologically Produced Structure in Deep-Sea Community Organization

最近对深海软基质群落的研究表明，物种的丰度受到厘米到毫米尺度过程的强烈影响，其中许多过程是由生物产生的结构（例如动物管）控制的。然而，对于这些结构在深海生物群落动态中的作用，还没有得到机制上的认识。Thistle博士和合作者Eckman博士正在评估多毛类形成的直径2厘米的沉积物凝结物影响圣地亚哥海槽中羽状桡足类丰度的机制。特别是，他们的努力将集中在测试对泥沙凝结的流体和颗粒动力效应的反应。他们使用潜水的ALVIN对个别沉积物凝结物和海底裸露区域进行取样，并开始现场实验。他们将完成对样品的分析，这些样品是在以前的巡航中获得的。对这些样品的分析将能够确定这些结构产生的水动力学和捕食-避难效应的重要性。前者在深海中尤其重要，因为那里沉积物的物理破坏率相对较低。此外，沉积物结核的大小与其他广泛分布的深海结构（例如锰铁结核）相当。可概括的。

Recent work in deep-sea, soft-substratum communities suggests that species' abundances are strongly affected by processes at centimeter-to-millimeter scales and that many of these processes are governed by biologically produced structures (e.g., animal tubes). However, no mechanistic understanding of the role of such structures in deep-sea community dynamics has been obtained. Dr. Thistle and collaborator Dr. Eckman are evaluating mechanisms by which the 2-cm-diameter sediment concretions built by polychaetes affect harpacticoid copepod abundances in the San Diego Trough. In particular, their efforts will be focused on testing responses to fluid- and particle- dynamic effects of sediment concretions. They have used the submersible ALVIN to sample individual sediment concretions and bare areas of the sea floor and to initiate in situ experiments. They will complete analysis of samples, which were obtained in previous cruises. The analysis of these samples will enable the determination the importance of hydrodynamic and predation-refuge effects created by these structures. The former, in particular, are likely to be especially important in the deep ocean, because of the relatively low rates of physical disruption of sediments there. Further, sediment concretions are comparable in size to other widespread, deep-sea structures (e.g., ferromanganese nodules). generalizable.