SGER: Fate and Transport of Carbon and sediments During a Mississippi River High Water Event

这项探索性研究小额赠款(SGER)奖将利用密西西比河2008年4月出现的~10年峰值流量，收集碳和沉积物通量的直接测量数据。特别是，这一罕见的事件为回答以下问题提供了一个理想的机会：1)不同来源的有机碳是如何被河流运输和处理的？2)洪水泛滥的河流如何将泥沙堆积和分配到邻近的湿地？将采用两个阶段的采样计划(船基和陆基)，在高峰流量事件期间对河流的悬沙、总有机碳、总有机碳年龄谱、营养物质和水文进行采样。将使用水声技术来确定洪水中河流的速度结构。使用寿命短、天然存在的放射性同位素(如7Be)将与x射线照相和经典沉积学方法结合使用，以量化最近的沉积。根据2005年密西西比河三角洲地区发生的环境破坏，再加上该地区对当前和未来气候变化的脆弱性，该项目解决了与社会、政策制定者和广泛的环境和工程科学家高度相关的问题。

This Small Grants for Exploratory Research (SGER) award will take advantage of the ~10-year peak-flow to occur in April, 2008, in the Mississippi River to gather direct measurements of carbon and sediment flux. In particular, this rare event provides an ideal opportunity to answer the following questions: 1) How is organic carbon of varying sources transported and processed by rivers? and 2) How do flooding rivers accumulate and distribute sediments to adjacent wetlands? A two stage sampling program (ship-based and land-based) will be employed to sample the suspended load, total organic carbon, bulk organic carbon age spectra,nutrients, and hydrology of the river during the peak-flow event. Hydro-acoustic techniques will be used to determine the velocity structure of the river in flood. Short-lived, naturally occurring radioisotopes(e.g. 7Be) will be used in combination with x-radiographs and classical sedimentology methods to quantify recent deposition. Long cores will be collected to ultimately compare these rates to long-term sedimentation histories.In light of the environmental destruction that occurred in the Mississippi River delta region in 2005, coupled with the region's vulnerability to current and future climate changes, this project tackles issues that are highly relevant to both society, to policy and decision makers, and to a broad spectrum of environmental and engineering scientists.