Effects of Irrigation On Growth of Polychaetes in Sedimentary Environments

9314681 MARINELLI底栖生物之间的相互作用的一个潜在的重要类别涉及底栖生物驱动的沉积环境的化学变化和其他生物的反应修改。 本项目将研究一种重要的动物活动，多毛类蠕虫灌溉洞穴，如何影响共生生物的生长。多毛类是沉积组合中的优势类群。根据物种特异性特征和群落组织，对穴灌的重要性进行了评价。 具体的问题包括：（1）共生生物对洞穴灌溉的影响程度如何？ 效益是否与灌溉洞穴的密度和分布以及灌溉频率有关？(2)个体所体验到的洞穴灌溉的益处在多大程度上取决于个体的生理或管道特性？(3)底栖生物群落中的竞争或捕食等其他生物过程如何影响多毛类之间的生物-化学相互作用？ 这些问题将采用一种综合办法加以评价，其中包括生物体的生物学以及沉积物中的迁移和反应过程。 这一方法包括在实验室和实地进行操纵实验，以及对影响底栖动物和/或受底栖动物影响的目标物质进行成岩建模。 规划期内的研究将探讨使用多毛类动物生长或生长潜力的生化指标的可行性。 这些指标包括（1）脂质成分分析和（2）RNA：DNA比值。 这些指数已被证明是有用的工具，检查营养状况和环境条件的海洋无脊椎动物和脊椎动物类群，包括桡足类，鱼类，棘皮动物，双壳类，甲壳类动物。 这些技术的发展，为多毛类提供了一个重要的替代方法，研究生态和环境问题的一个突出的分类在底栖生物组合。 规划研究是一个必要的先决条件，因为常用的方法评估的增长在多毛类动物可能是不够的。 综上所述，规划期内的研究和未来开发的研究项目将为底栖生物分布和相互作用的驱动力提供一个新的视角。 此外，他们将有重要的意义，了解不同的大型底栖动物组合如何影响溶质在沉积物中的传输，并评估在自然环境中的营养状况或生长潜力的多毛类。 ***

9314681 MARINELLI A potentially important class of interactions among infaunal organisms involves infaunal-driven changes in the chemistry of the sedimentary environment and responses of other organisms to the modification. This project will examine how one important infaunal activity, irrigation of burrows by polychaete worms, affects the growth of co-occurring organisms. Polychaetes are a dominant taxon in sedimentary assemblages. Evaluation of the importance of burrow irrigation is made in light of species-specific traits and community organization. The specific questions to be addressed include: (1) To what extent does burrow irrigation by co-occurring organisms affect the growth of individual polychaetes? Is the benefit related to the density and distribution of irrigated burrows, and the frequency of irrigation?; (2) To what extent is the benefit of burrow irrigation experienced by an individual dependent on the physiology or tube characteristics of the individual?; (3) How are biological-chemical interactions among the polychaetes affected by other biological processes, such as competition or predation, in benthic communities? These questions will be evaluated using a combined approach that incorporates the biology of organisms, and transport and reaction processes in sediments. This approach includes manipulative experimentation in the laboratory and field, and diagenetic modelling of target substances that affect, and/or are influenced by, infauna. The research in the planning period will examine the feasibility of using biochemical indices of growth or growth potential for the polychaetes. These indices include (1) analysis of lipid composition and (2) RNA:DNA ratios. These indices have proven useful as tools for examining nutritional status and environmental conditions for a number of marine invertebrate and vertebrate taxa, including copepods, fish, echinoderms, bivalves, and crustaceans. Development of these techniques for the polychaetes wo uld provide an important alternative method for examining ecological and environmental questions for a prominent taxon in benthic assemblages. The planning research is a necessary precursor because commonly-used methods of assessing growth in polychaetes are likely to be inadequate. Taken together, the research in the planning period, and the future to be developed research project, will provide a novel perspective on the forces which drive the distributions of, and interactions between benthic organisms. Furthermore, they will have important implications for understanding how different macrofaunal assemblages affect solute transport in sediments, and evaluating the nutritional status or growth potential of polychaetes in the natural environment. ***