Ecosystem Controls on the Biogeochemical Processing of Watershed-Derived Nitrogen in Tidal Rivers

随着沿海流域的发展，流域向河口的氮输入不断增加。需要更好地了解河口氮的命运，以改善对流域和河口耦合的管理。我们建议通过使用氮循环示踪剂来确定河口流域衍生硝酸盐的命运。这种示踪剂使测量氮如何在整个生态系统中从猎物到捕食者以及从水到沉积物的移动成为可能。我们将通过比较河流高流量和低流量时氮示踪剂在河口的移动来研究河流流量对氮循环的影响。同样，对有和没有广阔的潮滩的河口的氮流量进行比较，将显示河口的整体形状如何影响氮循环。来自这些示踪剂实验的氮循环数据将用于改进和测试预测河口流域衍生氮命运的模型。

ABSTRACTPeterson- 9815598 Nitrogen inputs from watersheds to estuaries are increasing due to coastal watershed development. A better understanding of the fate of nitrogen in estuaries is needed to improve management of coupled watersheds and estuaries. We propose to determine the fate of watershed-derived nitrate in estuaries by use of a nitrogen cycle tracer. The tracer makes it possible to measure how nitrogen moves throughout the ecosystem from prey to predators and from the water to sediments. We will study how river discharge affects the nitrogen cycle by comparing how the nitrogen tracer moves in estuaries during high and low river discharge. Likewise comparison of nitrogen flow in estuaries with and without extensive tidal flats will show how the overall shape of estuaries affects the nitrogen cycle. The nitrogen cycle data from these tracer experiments will be used to improve and test models that predict the fate of watershed-derived nitrogen in estuaries.