SGER: Development of a Great River Potamocorral and Applications for Determining Ecosystem Metabolism and Community Interactions among Potamoplankton

摘要[98-18273]由于采样的困难和危害，大河浮游生物群落的发展及其在确定生态系统代谢和群落间相互作用方面的应用尚未得到充分的研究。此外，在较小的河流上使用的标准抽样技术尚未被证明在充分表征这些复杂和瞬态系统方面有效。该项目将解决大型河流生态系统的功能问题。为了对圣劳伦斯河进行实证调查，pi和他们的本科生助手将构建一套“马铃薯群落”。涉及大型河流浮游生物的大规模现场实验目前超出了水生科学家的能力。这些研究人员打算测试食物网和生态系统代谢假设，这些假设与我们对大河作为异养系统的一般理论理解有关。具体实验将考虑：1)两种外来贻贝对浮游生物食物网的生态效应；2)不同水平浮游植物对生态系统代谢的影响；3)浮游贻贝对食浮游幼鱼生长的影响。在后一项实验中，研究人员假设，通过竞争性浮游生物，德莱森贻贝是圣劳伦斯鲈鱼和白眼鱼数量下降的一个因素。

Abstract98-18273ThorpDevelopment of a great river potamocorral and applications for determining ecosystem metabolism and community interactions among potamoplanktonLarge rivers have not been well-studied because of the difficulty and hazards associated with sampling. In addition, standard sampling techniques used on smaller rivers have not been shown to be effective in adequately characterizing these complex and transient systems. This project will address the functioning of large river ecosystems. The PIs and their undergraduate assistants will construct a set of "potamocorrals" in order to perform empirical investigations on the St. Lawrence River. Large-scale, in situ field experiments involving large river plankton are currently beyond the capabilities of aquatic scientists. These investigators intend to test food web and ecosystem metabolism hypotheses that relate to our general theoretical understanding of large rivers as heterotrophic systems. Specific experiments will consider: 1) the ecological effects of two exotic mussel species on plankton food webs; 2) the effects of differing levels of phytoplankton on ecosystem metabolism; and 3) the effects of mussel planktivory on the growth of planktivorous larval fish. In this latter experiment, the investigators hypothesize that dreissenid mussels are a factor in the decline of bass and walleye in the St. Lawrence through competitive planktivory.