RUI: Collaborative Research: Nitrogen fixers in a western river network: constraints and consequences

生物固氮是生物体将大气中的氮气转化为可用于其他生物过程的形式的过程。由于生物可利用氮常常限制植物生长，固氮是影响生态系统生产力、物种组成和食物网相互作用的关键过程。固氮的重要性已经在许多陆地生态系统中得到了研究，然而这一过程在溪流中的研究相对较少，通常被认为是受磷而不是氮的可用性限制的。地形、河流流量、物种组成和相互作用将作为限制美国西部河流网络固氮的潜在因素进行研究；将测试高分辨率数字高程数据作为这些分析的地形信息来源。这项工作的结果，结合将光和水力制度与数字地形模型联系起来的平行努力，将促进预测地图的发展，将生物固氮的控制和后果置于河网的物理和快速变化的环境背景中。通过将文科学习环境与大型研究小组的哲学和实验室设施相结合，将为领先的文理学院（一所女子学院）的科学和科学教育本科生提供研究机会和培训。与一个跨学科的科学家小组一起工作的机会将为不同的妇女群体提供实地生态学和科学过程的第一手经验，鼓励许多人在科学和科学教育方面寻求专业机会。

Biological nitrogen fixation is the process through which organisms convert nitrogen gas in the atmosphere to a form that can be used in other biological processes. Because biologically available nitrogen often limits plant growth, nitrogen fixation is a critical process that can influence ecosystem productivity, species composition, and food web interactions. The importance of nitrogen fixation has been studied in many terrestrial ecosystems, however this process has been relatively little studied in streams, which have often been thought to be limited by the availability of phosphorus rather than nitrogen. Topography, stream flow, and species composition and interactions will be examined as potential factors that limit nitrogen fixation in stream networks in the western United States; high resolution digital elevation data will be tested as a source of topographic information for these analyses. The results of this work, in combination with parallel efforts linking light and hydraulic regimes to digital topographic models, will facilitate the development of predictive maps that place the controls and consequences of biological nitrogen fixation into the physical and rapidly changing environmental context of river networks. Research opportunities and training will be provided to science and science education undergraduate students at the lead liberal arts institution, a women's college, by combining the liberal arts learning environment with access to the philosophies and lab facilities of large research groups. The opportunity to work with an interdisciplinary team of scientists will provide a diverse group of women first-hand experience in field ecology and the scientific process, encouraging many to pursue professional opportunities in science and science education.