Dissertation Research: Phosphorus Cycling in Shallow Freshwater Ecosystems

论文研究：浅层淡水生态系统中的磷循环

• 批准号: 0910008
• 负责人: Stephen Hamilton
• 金额: $ 1.5万
• 依托单位: Michigan State University
• 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: 2009-04-15 至 2011-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0910008&HistoricalAwards=false
• 关键词: Dissertation; Research; Phosphorus; Cycling; Shallow

Phosphorus is a nutrient required by all living things, but its use in industrial fertilizers and other products has increased its occurrence to polluting levels in many agricultural and urban watersheds. Excess phosphorus often causes eutrophication in freshwater ecosystems. Eutrophication remains a pervasive problem in the U.S. and can impact aquatic ecosystems as blooms of toxic phytoplankton, reduced water clarity, changes in plant communities, and fish kills. Due to the ability of the sediments to accumulate phosphorus, wetlands are often managed to store phosphorus and prevent entry into downstream ecosystems. The ability of wetland sediments to bind phosphorus varies, and at times wetlands can become sources of, rather than sinks for, phosphorus. The ways in which phosphorus binds to and is released from sediments has been studied extensively in deep lakes, but less so in shallow wetlands. Shallow wetlands differ from lakes in that they often dry and re-flood and tend to have sediments with more organic matter (decomposing plant material). This study investigates how water level fluctuations influence phosphorus binding and release in wetland sediments of varying characteristics.The findings of this research will not only inform understanding of how sediment controls plant growth in freshwater ecosystems through P release, but will have direct applications to management of many freshwater ecosystems. The findings of this research will provide insight into how best to manage wetlands to promote phosphorus accumulation in sediments and prevent its release to downstream ecosystems. In addition to management implications of the research itself, researchers will educate the general public through development of K-12 curricula aimed at teaching the definition, ecology, and functional roles of wetlands and wetland sediment. Lesson plans will be developed through a partnership with teachers at Lawton Community Schools in Southwest Michigan, and will be taught to students there with direct assessment of student learning. Assessments of student learning from lesson plans will aide in refining lesson plans for publication in education literature. Finally, undergraduate students interested in ecology will be given opportunities to conduct independent research experiences as part of this project.

磷是所有生物所需的一种营养素，但是在许多农业和城市流域中，其在工业肥料和其他产品中的使用已增加了其污染水平的发生。 过量的磷通常会在淡水生态系统中引起富营养化。 在美国，富营养化仍然是一个普遍的问题，可能会影响水生生态系统，因为有毒浮游植物的绽放，降低水的清晰度，植物群落的变化和杀死鱼类。 由于沉积物积聚磷的能力，湿地通常被设法存储磷并防止进入下游生态系统。 湿地沉积物结合磷的能力各不相同，有时湿地可能成为磷的来源，而不是下沉的磷。 磷与沉积物结合并从沉积物中释放的方式已在深湖中进行了广泛的研究，但在浅湿地中却较少。 浅湿地与湖泊不同，因为它们经常干燥和重新灌木丛，并且往往具有更有机物质（分解植物材料）的沉积物。 这项研究调查了水位波动如何影响不同特征的湿地沉积物中的磷结合并释放。这项研究的发现不仅将有助于了解沉积物如何通过P释放来控制淡水生态系统的植物生长，而且将直接应用于许多淡水生态系统的管理。 这项研究的发现将提供有关如何最好地管理湿地以促进磷在沉积物中积累的洞察力，并防止其释放到下游生态系统中。 除了研究本身的管理意义外，研究人员还将通过开发K-12课程来教育公众，旨在教授湿地和湿地沉积物的定义，生态和功能作用。 课程计划将通过与密歇根州西南部Lawton社区学校的老师合作制定，并通过直接评估学生学习的学生进行教导。 从教训计划中对学生学习的评估将有助于完善教育文献出版的课程计划。 最后，对生态学感兴趣的本科生将有机会作为该项目的一部分进行独立的研究经验。