Linking Hydrologic Exchange to Nitrogen Cycling at the Groundwater-Stream Water Interface

将水文交换与地下水-溪流水界面处的氮循环联系起来

• 批准号: 9420282
• 负责人: Alan Jackman
• 金额: $ 33.5万
• 依托单位: University of California-Davis
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1995
• 资助国家: 美国
• 起止时间: 1995-07-01 至 2001-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9420282&HistoricalAwards=false
• 关键词: Linking; Hydrologic; Exchange; Nitrogen; Cycling

JACKMAN, TRISKA, and DUFF The interface between ground water and surface water is a dynamic boundary where strong gradients in nutrients, dissolved oxygen, and redox potential occur. This interface zone, termed the hyporheic zone, exerts considerable influence on the biotic communities of streams and rivers, the flux of nutrients from terrestrial to aquatic ecosystems, and upon the hydrology of streams, rivers, and floodplains. This project focuses upon this dynamic interface with emphases on the cycling of nitrogen and effects on aquatic macrophytes. The project combines a thorough study of hydrology of the hyporheic zone with the biogeochemistry and biological interactions at this interface. This research will yield significant progress in coupling the hydrology and biogeochemistry of catchments at the terrestrial/aquatic interface. Riparian zones have been shown to provide buffering capacity for reducing the import of excessive nutrients of terrestrial origin into aquatic ecosystems. These initial studies on this filtering capacity of this interface, however, have not been coupled to a rigorous characterization of the hydrologic flow paths in space and time within this zone. This project quantifies major components of nitrogen cycling along known flow paths and follows the impact of these processes to the biota of stream and river ecosystems.

地下水和地表水之间的界面是一个动态边界，在这里，营养物、溶解氧和氧化还原电位的梯度很强。这个界面区，被称为潜流区，对溪流和河流的生物群落，从陆地到水生生态系统的营养物质的通量，以及溪流、河流和洪泛平原的水文具有相当大的影响。本项目重点研究这一动态界面，重点研究氮的循环及其对水生植物的影响。该项目将潜流带的水文研究与该界面的生物地球化学和生物相互作用结合起来。该研究将在陆水界面流域水文与生物地球化学耦合研究方面取得重大进展。河岸带已被证明具有缓冲能力，可减少过量陆源营养物质进入水生生态系统。然而，这些关于该界面过滤能力的初步研究并没有与该区域内空间和时间上的水文流动路径的严格表征相结合。该项目量化了沿已知流动路径氮循环的主要组成部分，并跟踪了这些过程对溪流和河流生态系统生物群的影响。