Collaborative Resarch: Terrestrial Support of Lake Food Webs: A Multi-Isotope Approach

合作研究：湖泊食物网的陆地支持：多同位素方法

• 批准号: 0917858
• 负责人: Stephen Carpenter
• 金额: $ 51.94万
• 依托单位: University of Wisconsin-Madison
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-01 至 2013-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0917858&HistoricalAwards=false
• 关键词: Collaborative; Resarch; Terrestrial; Support; Lake

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).The support of animals in ecosystems ultimately comes from two sources: primary production within an ecosystem (e.g. newly grown plant material) or primary production imported from other ecosystems (e.g. inputs of terrestrial material to an aquatic system). In lakes, it is well known that external inputs are large compared to internal primary production, but how these materials support lake food webs is less well documented. Deuterium is a stable isotope of hydrogen and deuterium content of terrestrial and aquatic primary producers is significantly different. Carbon and nitrogen stable isotope ratios, while less well contrasted, are also helpful, when coupled with deuterium, in discriminating sources of consumer support. Thus, integrated analysis of hydrogen, carbon and nitrogen stable isotopes can distinguish the use of internal versus external primary production by lake animals and microbes. In this proposal the PIs will use measurements of the stable isotopes carbon, nitrogen, and hydrogen along with a new modeling approach to test hypotheses about variation in terrestrial subsidies of aquatic consumers and how these vary among different types of lakes. The multi-isotope approach will also be applied to a whole lake nutrient fertilization experiment to test differences in the support of benthic versus pelagic consumers by external organic matter. This research will directly measure variation in the support of consumers by external materials and contribute to understanding the drivers of variation among ecosystems in these processes. Several undergraduates and 2 graduate students will receive training through this research in ecosystem ecology, limnology, modeling, and stable isotope methodology. Results from this research will contribute directly to courses taught by the PIs. The stable isotope model to be utilized in this study is a tool that will be of interest to other researchers. The model which runs on open access software will be made available through our website along with documentation, tutorials, and test data. In addition, the PIs propose to sponsor a half-day workshop at a national meeting on modeling methods in isotopic studies. Providing a multi-isotope model approach to the larger research community will be a significant component of the Broader Impacts of this project.

该奖项是根据2009年的《美国回收与再投资法》（公法111-5）资助的。生态系统中动物的支持最终来自两个来源：生态系统内的主要生产（例如，新生长的植物材料）或从其他生态系统中进口的主要产量（例如，向水生材料的投入到水生系统）。 在湖泊中，众所周知，与内部初级生产相比，外部投入很大，但是这些材料如何支持湖泊食品网。 氘是陆生和水生生产者的氢和氘含量的稳定同位素。 碳和氮稳定的同位素比虽然对比度不佳，但在与氘相结合的情况下，在区分消费者支持的来源时也很有帮助。 因此，对氢，碳和氮稳定的同位素的综合分析可以区分湖动物和微生物对内部生产与外部产生的使用。 在此提案中，PI将使用稳定的同位素碳，氮和氢的测量以及一种新的建模方法来测试有关水生消费者陆生质量补贴变化的假设，以及这些方法如何在不同类型的湖泊中变化。 多同位素方法也将应用于整个湖营养物受精实验，以测试外部有机物对底栖消费者的支撑差异。 这项研究将通过外部材料直接衡量消费者支持的变化，并有助于了解这些过程中生态系统之间的变化驱动因素。 几名大学生和2名研究生将通过这项研究的生态系统生态学，羊水学，建模和稳定的同位素方法来接受培训。 这项研究的结果将直接为PIS教授的课程做出贡献。本研究中要使用的稳定同位素模型是其他研究人员感兴趣的工具。 在开放访问软件上运行的模型将通过我们的网站以及文档，教程和测试数据提供。 此外，PIS建议在同位素研究中的全国建模方法会议上赞助半天的研讨会。 为更大的研究社区提供多同位素模型方法将是该项目更广泛影响的重要组成部分。