Collaborative Research: Terrestrial Carbon Subsidies of Aquatic Food Webs

湖泊中的大部分有机碳来自周围的陆地生态系统。湖泊中这种陆地碳的退化意味着湖泊的食物网潜在地受到外部来源的支持，而不仅仅是内部初级生产。之前在小型湖泊中使用无机碳-13添加剂的实验表明，水生食物网在陆地上得到了显著的支持。该项目将直接解决湖泊中食物网的陆地支持的相对重要性，这些湖泊的面积是以前研究的湖泊的4-10倍。碳-13将被添加到两个大型湖泊中，并利用研究人员开发的几个模型进行分析。结果将决定这些较大湖泊的陆地补贴的重要性，这些湖泊在威斯康星州和密歇根州的北部高地处于面积最大的四分之一，代表了全球一大类温带湖泊。这项研究将通过评估湖泊大小的差异是否影响食物网和碳循环，有助于在景观背景下理解湖泊。该项目的更广泛影响包括促进公众对湖泊生态系统的了解，以及为研究生和本科生提供研究培训。这些成果将纳入正在进行的关于北高地湖区未来的外联工作。

Much of the organic carbon in lakes originates from surrounding terrestrial ecosystems. Degradation of this terrestrial carbon in lakes implies that lake food webs are potentially supported by external sources, rather than solely by internal primary production. Prior experiments in small lakes using inorganic carbon-13 additions revealed significant terrestrial support of aquatic food webs. This project will directly address the relative importance of terrestrial support of food webs in lakes 4-10 times the size of lakes studied previously. Carbon-13 will be added to two large lakes and analyzed with several models developed by the investigators. Results will determine the importance terrestrial subsidies in these larger lakes that are in the top quartile for size in the Northern Highlands of Wisconsin and Michigan and representative of a large class of temperate lakes globally. This research will contribute to understanding lakes in a landscape context by assessing whether differences in lake size influence food webs and carbon cycling. Broader impacts of this project include promoting public understanding of lake ecosystems as well as research training for graduate and undergraduate students. Results will be incorporated into an ongoing outreach effort on the future of the Northern Highland Lake District.