Omnivorous Fish and the Stability of Aquatic Food Webs

奖项摘要 Michael J. VanniMiami University提案编号： DEB-9982124 PI建议研究杂食性鱼类（砂囊鱼）在水生食物网对营养物质大脉冲形式扰动的抵抗力和恢复力中的作用。 他们假设，像这些鲱鱼这样的杂食性鱼类的食物网更稳定（即，抵抗力和弹性）在repines的外来营养扰动比那些没有杂食性鱼类。 增强的稳定性可能是由于大量的稳定供应的营养物质运输的杂食性鱼类从沉积物中或通过将杂食性鱼类在食物网中形成的额外的营养链。 这项工作的目标是测试预测所产生的杂食稳定性假说，并确定潜在的机制，负责观察到的变化的稳定性。 复制池塘实验将进行评估鱼类如何影响阻力和恢复力的食物网脉冲的营养物质，如果是这样的话，无论是通过营养运输或通过食物网结构的作用，或两者兼而有之。 模型也将被用来探索杂食性鱼类在一系列生态系统结构和扰动类型的水生食物网的稳定性的作用。

AWARD ABSTRACT Michael J. VanniMiami UniversityProposal Number: DEB-9982124The PI proposes to investigate the role of an omnivorous fish, the gizzard shad, in the resistance and resilience of aquatic food webs to perturbations in the form of large pulses of nutrients. They hypothesize that food webs with omnivorous fish, like these shad, are more stable (i.e., resistant and resilient) in repines to perturbations of allochthonous nutrients than are those without omnivorous fish. The enhanced stability might be due to the large steady supply of nutrients transported by omnivorous fish from sediments or to the additional trophic links formed by incorporating the omnivorous fish in the food webs. The objectives of this work are to test predictions generated by the omnivory-stability hypothesis and to determine the underlying mechanisms responsible for observed changed in stability. Replicated pond experiments will be performed to assess how fish influence resistance and resilience of food webs to pulses of nutrients, and if so, whether the mechanism is via nutrient-transport or via a food web-structure role, or both. Modeling will also be used to explore the role of omnivorous fish in the stability of aquatic food webs over a range of ecosystem structures and perturbation types.