Chemical Modulation of Marine Deposit Feeding

沉积物进食对于控制到达海底的所有颗粒的转移或埋藏非常重要，其影响范围从流经营养网流到地层记录的分辨率。然而，除了少数几个值得注意的例外，人们仍然很难确定为沉积物提供燃料的资源。通过隔离食品检测和消化过程的化学检查和生物实验，该项目将尝试推广用于创建一对这些例外的方法。这个项目将以理论为指导，该理论预测当物质通过有机体的肠道时，净吸收率最大。该项目的重点是调节导致这种最大化的过程的三个具体过程，即气味、味道和跨越肠壁的吸收。气味和味道将根据对扩散或接触的化合物的反应，用化学和操作定义来确定。在实验室中引起摄食反应的化合物的有效性将在野外测试它们作为引诱剂的作用。虽然感知能力和营养价值之间的相关性并不完美，但这种不完美会影响这些动物感知食物存在的能力，因此它本身是有意义的。摄取食物的最佳肠道滞留时间的概念侧重于食物质量的动力学定义，其确定也可能导致确定可用食物资源。对消化的食物在肠壁中吸收的测量将允许在来自普吉特湾和缅因湾的一系列动物身上明确测试这些吸收最大化的模型。

Deposit feeding is important in gating the transfer or burial of all particles that arrive at the seafloor, with implications ranging from flow through trophic webs to resolution of the stratigraphic record. The resources that fuel deposit feeding, however, remain poorly identified-with a few notable exceptions. By chemical examination and biological experimentation that isolate the processes of food detection and digestion this project will attempt to generalize the approach used to create a pair of those exceptions. This project will be guided by theory that predicts maximization of net absorption rate as material transits the gut of an organism. The focus of the project is on three specific processes that modulate processes leading to this maximization, namely smell, taste and absorption across the gut wall. Smell and taste will be determined with chemical, operational definitions based on response to diffused or contacted compounds. The efficacy of compounds that elicit feeding responses in the laboratory will be tested for their roles as attractants in the field. While the correlation between sensing ability and nutritional value will not be perfect, the imperfection affects the ability of these animals to sense the presence of food and so itself is of interest. The concept of optimal gut retention times of ingested food focuses attention on a kinetic definition of food quality, whose determination will also likely result in identification of usable food resources. Measurements of absorption of digested foods into the gut wall will allow explicit tests of these models of absorption maximization on a series of animals from Puget Sound and the Gulf of Maine.