Collaborative: Assessing Effects of Food Web Structure on Patterns of Productivity and Trophic Transfer in Lake Food Webs

9520884卡里克这项研究将考察上层食物网配置对加利福尼亚州卡斯尔湖远洋生态系统结构、碳流和生产力的影响。这项研究建立在整个湖泊食物网操作的基础上，并增强了一个发展良好的长期数据集的价值和重要性，该数据集强调了初级生产力的生物和气候决定因素。在这个项目中，城堡湖的食物网结构将通过改变彩虹鲑鱼的放养率来操纵。这种操作将减少彩虹鲑鱼的数量，从而增加金色闪光体、桡足类和细菌的微型食草动物的数量。通过测量微生物和初级生产量的速率以及评估后生动物和鱼类的种群和生长动态，这项研究将估计在不同食物网配置下的生产模式和通过食物网的碳流。城堡湖食物网对营养结构操纵的反应将与未受干扰的参考地点悬崖湖的并发动态进行比较。除了整个湖泊的操纵，还将进行一系列中观和微观实验，以解决决定食物网络结构的机制。这项研究将在定量模拟模型中进行总结和综合。这一量化框架将允许综合各种空间和时间尺度的调查，并将能够在城堡湖生态系统的长期数据记录的背景下解释微生物和基于经典的食物网动态。

9520884 Carrick This research will examine the effect of upper food web configuration on pelagic ecosystem structure, carbon flow, and productivity in Castle Lake, California. This research builds on a whole lake food web manipulation, and augments the value and importance of a well-developed long term data set emphasizing biological and climatic determinants of primary productivity. In this project, food web configuration in Castle Lake will be manipulated by varying the stocking rates of rainbow trout. The manipulation will reduce rainbow trout, thus increasing the abundance of golden shiners, copepods, and micrograzers of bacteria. By measuring rates of microbial and primary production and assessing population and growth dynamics of metazoans and fish, this research will estimate patterns of production and carbon flow through the food web under different food web configurations. The response of the Castle Lake food web to trophic structure manipulation will be compared to concurrent dynamics in an unperturbed reference site, Cliff Lake. In addition to the whole lake manipulation, a series of meso- and microcosm experiments to address mechanisms determining food web structure will be conducted. This research will be summarized and synthesized within a quantitative simulation model. This quantitative framework will allow integration from investigations spanning a variety of spatial and temporal scales, and will allow interpretation of microbial and classic-based food web dynamics within the context of the long-term data record for the Castle Lake ecosystem.