OPUS: Nutrient cycling by animals in freshwater ecosystems

该项目旨在提供对动物在淡水生态系统中营养循环中所起作用的了解。该项目将利用和综合首席调查员在20年期间收集的数据。动物可以通过多种方式影响植物的营养物质(如氮和磷)的供应。例如，所有动物都以废物的形式释放营养物质，有些动物可以通过运动将营养物质转移到很远的地方。然后，这些营养物质就可以为植物所用，可能会促进植物的生长。虽然动物的重要性在许多情况下都得到了证明，但还没有综合说明动物在淡水生态系统(湖泊、池塘、溪流和河流)的营养循环中的作用。这个项目将利用以前收集的数据来制作一系列科学论文，描述和分析淡水动物在营养循环中所扮演的角色。此外，它还将为本科课程制作两个批判性思维练习，帮助学生理解营养循环的概念。这个项目的更广泛的影响是巨大的和多样的。营养循环是最重要的“生态系统服务”之一(发生在自然界中对人类具有经济价值的过程)；营养循环维持生产力，从而维持生态系统为人类消费提供食物、纤维或材料的能力。此外，一些生态系统吸收了太多的营养物质，这可能会导致藻类大量繁殖，随后水质恶化。因为动物会影响藻类和植物的营养供应，它们会影响这些生态系统服务和水质问题。因此，这一综合将提供关于动物在生态系统服务和水质中的作用的有价值的信息。此外，批判性思维练习将为本科生提供动手的、基于探究的营养循环方法，以及它与这些环境问题的关系。营养循环对学生来说是一个很难掌握的概念，这些练习旨在促进对这一材料的学习，并提高学生处理和分析数据的能力。

This project is designed to provide an understanding of the role that animals play in the cycling of nutrients in freshwater ecosystems. The project will utilize and synthesize data collected by the principal investigator over a 20-year period. Through a variety of ways, animals can affect the supply of nutrients (such as nitrogen and phosphorus) to plants. For example, all animals release nutrients as waste products, and some animals can move nutrients great distances via their movements. These nutrients then become available to plants, perhaps increasing plant growth. While the importance of animals has been demonstrated in many situations, there has not been a synthesis of the role of animals in nutrient cycling in freshwater ecosystems (lakes, ponds, streams and rivers). This project will utilize previously collected data to produce a series of scientific papers describing and analyzing the roles that freshwater animals play in nutrient cycling. In addition, it will generate two critical thinking exercises for undergraduate classes that will help students understand nutrient cycling concepts.The broader impacts of this project are substantial and diverse. Nutrient cycling is one of the most important "ecosystem services" (processes occurring in nature that have economic value to humans); nutrient cycling sustains productivity, and hence the capacity of ecosystems to provide food, fiber or materials for human consumption. In addition, some ecosystems receive too many nutrients, which can lead to blooms of algae and subsequent deterioration of water quality. Because animals can affect the supply of nutrients to algae and plants, they can impact these ecosystem services and water quality problems. Thus, this synthesis will provide valuable information on the roles of animals in ecosystem services and water quality. In addition, the critical thinking exercises will provide undergraduate students with a hands-on, inquiry based approach to nutrient cycling and how it relates to these environmental issues. Nutrient cycling can be a difficult concept for students to grasp, and these exercises are designed to facilitate learning of this material, and to improve students' abilities to manipulate and analyze data.