Doctoral Dissertation Enhancement Project: Deciphering Arsenic Migration Pathways within the Mekong Delta, Cambodia

0751701Fendorf该奖项支持Scott Fendorf博士及其学生与Michael Sampson博士（柬埔寨金边国际资源开发中心主任）之间的博士论文强化项目。该项目将涉及破译柬埔寨湄公河三角洲内砷的迁移路径。砷是一种有毒的、致癌的类金属，在地壳中随处可见，对全世界数百万人产生了不利影响。东南亚的许多人都接触到被砷污染的饮用水。尽管地下砷源引起了广泛的中毒和关注，但导致地下水砷的生物物理化学过程仍未得到解决。研究人员建议确定在东南亚的沉积盆地中将砷释放到水相中的过程。柬埔寨的湄公河三角洲将作为该研究的示范系统。为了完成这个项目，他们将利用一套现场测量，完整的岩心浸出实验，以及与本地微生物群落的沉积物孵育。一旦完成，他们将提供砷在沉积物中释放和运输的具体说明，这将限制砷在哪里是一个问题污染物的预测。目前，特别是在东南亚的发展中国家，迫切需要这样的预测，以应对与广泛摄入受砷污染的水有关的健康危机。本研究的结果将提供近地表热带沉积物中砷释放的机理描述，包括相关的生物、化学和水文过程。沉积物导致砷释放的生化条件将受到限制，这些传播的信息将用于更好地预测东南亚地区砷浓度升高风险较高的地点。该项目将训练美国研究生以及一些年轻的柬埔寨科学家获取和分析实地数据，从而为柬埔寨多年的内战耗尽的知识基础增加新的资源。该项目还将为美国研究生提供全球研究经验。预计该学生将在项目完成后与他的柬埔寨合作者保持多年的科学联系。

0751701FendorfThis award supports a doctoral dissertation enhancement project between Dr. Scott Fendorf, his student and Dr. Michael Sampson, Director, Resource Development International in Phnom Penh, Cambodia. The project will involve deciphering Arsenic migration pathways within the Mekong Delta in Cambodia. Arsenic, a toxic and carcinogenic metalloid found throughout the earth's crust, is adversely affecting millions of individuals worldwide. Many individuals in Southeast Asia are exposed to drinking water contaminated with arsenic. Despite the widespread poisoning and resulting attention on subsurface arsenic sources, biophysicochemical processes leading to Arsenic groundwater remain unresolved. The researchers propose to define the processes responsible for releasing Arsenic into the aqueous phase within the sedimentary basins of Southeast Asia. The Mekong Delta of Cambodia will serve as a model system for the study. In accomplishing this project they will utilize a suite of field measurements, intact core leaching experiments, and sediment incubations with native microbial communities. Once completed, they will provide a specific illustration of arsenic release and transport within sediments, which will constrain predictions of where Arsenic is a problem contaminant. Such predictions are desperately needed to combat the current health crisis associated with the widespread ingestion of arsenic contaminated waters, especially in the developing nations of Southeast Asia. The results of this study will provide a mechanistic description of Arsenic release from near-surface tropical sediments, inclusive of relevant biological, chemical, and hydrologic processes. The biochemical conditions with sediments conductive to Arsenic release will be constrained, and this disseminated information will be used to better predict locations which may be at higher risk of elevated Arsenic concentrations within Southeast Asia. The project will train the U.S. graduate student, as well as some young Cambodian scientists, to acquire and analyze field data, adding to the intellectual base now depleted by many years of the civil war. The project will also provide the U.S. graduate student with a global research experience. It is anticipated that the student will maintain scientific connections with his Cambodian collaborators for many years after the project is completed.