Collaborative Research: Across the Salinity Transition -- Changes in N and P Biogeochemistry Along an Estuarine Salinity Gradient

水生生态系统受到氮(N)和磷(P)过度富集的威胁。由于不清楚的原因，通常在淡水中P富集影响最大，而在咸水中N富集影响最大。本研究的目的是了解河口从淡水到咸水的过渡过程中N和P的生物地球化学变化。该项目将测量沿帕塔克森特河河口盐度转变的N和P的输入和移除，研究流域衍生颗粒P的重要性，并测试关于N， P，铁和硫循环相互作用的假设。氮和磷的转化和释放将通过沿盐度梯度孵育沉积物岩心来测量。盐度效应的机制将通过实验改变海水、海盐、硫酸盐和硝酸盐在孵育岩心上的浓度来研究。研究结果将有助于指导沿海生态系统的营养管理。这是一个与Thomas Jordan （DEB-0212543）合作的项目

Aquatic ecosystems are threatened by over enrichment with nitrogen (N) and phosphorus (P). For unclear reasons, P enrichment generally has the greatest impact in freshwater while N enrichment has the greatest impact in saltwater. The goal of this study is to understand how the biogeochemistry of N and P change along the transition from freshwater to saltwater in an estuary. The project will measure inputs and removals of N and P along the salinity transition of the Patuxent River estuary, investigate the importance of watershed-derived particulate P, and test hypotheses about interactions of N, P, iron and sulfur cycles. Transformations and releases of N and P will be measured by incubating sediment cores from along the salinity gradient. The mechanisms of salinity effects will be investigated by experimentally altering concentrations of seawater, sea salts, sulfate, and nitrate over incubated cores. The results will help guide nutrient management in coastal ecosystems. This is a collaborative project with Thomas Jordan (DEB-0212543)