Collaborative Research: Alternative Carbon Sources for Lake Food Webs

空间合作研究：湖泊食物网的替代碳源大多数生态系统被认为是由系统边界内植物的光合作用驱动的。湖泊尤其是藻类和水生植物如何支持包括鱼类在内的食物网的教科书例子。然而，植物产量往往不能很好地预测鱼类和无脊椎动物的产量。生态学家早就知道，湖泊从其流域获得了大量的有机物质输入。最近的研究表明，这种陆地有机物质具有潜在的可获得性，这表明陆地有机物质可能在支持包括顶级食肉动物在内的湖泊食物网方面具有重要意义。该项目将通过在整个湖泊中添加一系列稳定的碳同位素来解决这个问题，这将在陆地固定碳和水生植物固定碳的同位素组成上产生强烈的对比。通过稳定同位素添加实验和计算机模拟的结合，这项研究将提供生态系统级别的测试，以检验陆地有机质和水生食物网之间联系的重要性。

0075114PaceCollaborative Research: Alternative carbon sources for lake food websMost ecosystems are viewed as driven by photosynthesis deriving from plants within the system's boundaries. Lakes in particular are textbook examples of how algae and aquatic plants support food webs including fish. Yet, plant production is often a poor predictor of fish and invertebrate production. Ecologists have long known that lakes receive significant inputs of organic matter from their watersheds. Recent work demonstrates that this terrestrial organic matter is potentially available, suggesting terrestrial organic matter may be significant in supporting lake food webs including top carnivores. This project will address this question by a series of whole lake additions of a stable isotope of carbon which will produce a strong contrast in isotopic composition between terrestrially-fixed carbon and carbon fixed by aquatic plants. Through a combination of stable isotope addition experiments and computer modeling, this research will provide an ecosystem-level test of the importance of the connections between terrestrial organic matter and aquatic food webs.