Chemically Mediated Interactions in a Sedimentary Assemblage

化学环境和物种动态之间的相互作用对生态系统至关重要。例如，补充、捕食和生物干扰通常是由特定的生物化学物质调节的，其变化可以深刻地影响群落的动态。该项目将研究生物溴化芳烃的存在与海洋沉积组合中三个营养级别成员的动力学之间的耦合。该项目利用蠕虫产生的溴代芳烃及其对周围栖息地的污染作为一个模式系统来研究以下问题：1.这些化合物的存在如何影响捕食率和扰动率？2.细菌在控制沉积物污染程度方面有多重要？根据PI之前的研究，已知在这些溴代芳烃的存在下，某些物种的招募会从根本上减少。然而，关于这些化合物对系统中的主要干扰力--咬沉积物和挖泥的捕食者--的影响，以及维持沉积物中这些有毒溴化酚水平的过程，缺乏信息。通过各种实验室和现场实验，本研究项目将研究生物来源的溴代芳烃对这些过程的影响。鉴于全球海洋沉积生境中产生溴代芳烃的类群的丰度，这些化合物可能在海洋沉积群落中作为结构力量非常重要。

The interplay between the chemical environment and the dynamics of species is of fundamental importance to ecosystems. Recruitment, predation, and biotic disturbance, for example, are commonly mediated by specific biogenic chemicals whose alteration can profoundly affect the dynamics of the community. This project will study the coupling between the presence of biogenic brominated aromatics and the dynamics of members of three trophic levels in a marine sedimentary assemblage. The project utilized the production of bromoaromatics by a worm and its contamination of the surrounding habitat as a model system for examining the following questions: 1. How does the presence of these compounds affect rates of predation and disturbance? and 2. How important are bacteria in controlling the level of sediment contamination? Based on the PI's prior research it is known that recruitment of some species is radically reduced in the presence of these bromoaromatics. However, there is a lack of information on the effects of these compounds on the major disturbance forces in the system, sediment-biting and digging predators, and on the processes that maintain the level of these toxic brominated phenols in the sediment. Using a variety of laboratory and field experiments, this research project will investigate the effects of the biogenic bromoaromatics on these processes. Given the global abundance in marine sedimentary habitats of taxa producing brominated aromatics, these compounds may be very important as structuring forces in marine sedimentary communities.