RAPID: COLLABORATIVE RESEARCH: The 2011 Historic High Flows in the Atchafalaya Basin: How will Hydrologic transport Alter Nutrient Retention (C and N)?

快速：合作研究：2011 年阿查法拉亚盆地历史性高流量：水文输送将如何改变养分保留（C 和 N）？

• 批准号: 1141417
• 负责人: Richard Keim
• 金额: $ 0.71万
• 依托单位: Louisiana State University Agricultural Center
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-06-15 至 2012-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1141417&HistoricalAwards=false
• 关键词: RAPID; COLLABORATIVE; RESEARCH; 2011; Historic

The diversion of nutrient-rich water through forested wetlands--especially within the Lower Mississippi River Basin?is one proposed approach to reduce nutrient export to coastal estuaries. The primary objective of this research is to quantify nutrient retention and carbon mineralization as river water is transported through the Atchafalaya Basin Floodway System (ABFS). By characterizing water transported via channelized sections of the basin in contrast to the un-channelized spillway including the forested swamps, the research team expects to find enhanced nutrient removal within water diverted through the spillway due to increased residence time and enhanced contact with floodplain sediments. Samples will be collected across the basin over the flood period (12 weeks). Water isotopes and conservative anions will be measured to quantify water sources and infer water residence time. Nutrients (phosphorus and nitrogen species) will be measured to quantify system processing and delineate spatial differences across the ABFS.Although diverting water is a proposed approach to reduce nutrient export, and associated hypoxic zone extent, in the Gulf of Mexico, the effect of very large-scale diversion on the magnitude of nutrient reduction is not well understood. The current flooding in the Lower Mississippi (highest levels since 1927) has resulted in the Army Corps of Engineers opening the Morganza Spillway into the ABFS for the first time since 1973. The opportunity to explore the fate of the nutrient-rich Mississippi water through the ABFS is unprecedented and will provide valuable insight into the coupling of hydrology and biogeochemistry of the Atchafalaya River and Floodplain. This study will provide insights on nutrient reduction associated with large scale diversion of spring runoff water.

通过森林湿地--尤其是在密西西比河下游流域--引流营养丰富的水，是减少向沿海河口输出营养物质的一种拟议方法。这项研究的主要目标是量化河水通过阿查法拉亚盆地防洪道系统(ABFS)输送时的营养物质保持和碳矿化。通过与包括森林沼泽在内的非沟道化溢洪道相比，研究小组对通过盆地沟道化部分输送的水进行了表征，研究小组预计，由于停留时间增加和与泛滥平原沉积物的接触增加，通过溢洪道转移的水中的养分去除效果会增强。将在洪水期间(12周)在整个流域收集样本。将测量水的同位素和保守的阴离子，以量化水源并推断水的停留时间。营养物质(磷和氮的种类)将被测量，以量化整个ABFS的系统过程和描绘空间差异。尽管调水是一种建议的方法来减少营养物质的输出，以及相关的缺氧区范围，但在墨西哥湾，非常大规模的转移对养分减少幅度的影响还没有被很好地了解。目前密西西比河下游的洪水(自1927年以来的最高水位)导致陆军工程兵部队自1973年以来首次开放进入ABFS的摩根萨溢洪道。通过ABFS探索营养丰富的密西西比河水的命运的机会是前所未有的，将为了解阿查法拉亚河和洪水平原的水文学和生物地球化学的耦合提供宝贵的见解。这项研究将为大规模引泉径流带来的养分减量提供启示。