Collaborative Research: Investigation of hydrologic and biogeochemical controls on arsenic mobilization at a field site in Munshiganj, Bangladesh

CBET-0651968 Jennifer Jay，UCLA（负责人）CBET-0651678 Charles Harvey，MIT合作研究：在Munshiganj的一个现场调查水文和地球化学对砷活动的控制，该项目将调查最近观察到的现象如何影响砷（As）通过在孟加拉国的一个稻田地点部署水文和地球化学传感器，并通过实地和实验室微观生态系统/中观生态系统实验，动员了大量的水资源。具体而言，最近在现场进行的初步研究证明，土壤中犁盘下存在气相，也证明了渗透水的快速向下运动。地球化学和水力特性的趋势表明，昼夜过程，可能是植物引起的，可能是重要的。该项目将检验水文过程（由于气压变化和植物蒸散）和植物引起的化学变化（由于根系释氧和地表水变化）驱动现场观察到的每日振荡的假设。这是一个具有挑战性的科学问题，并与嵌入式传感器网络进行了全面的实验和观察将被用来研究这个问题。这项研究的社会影响很大。砷在美国和全球都是一个严重的污染问题，它在孟加拉国造成了可怕的健康后果。拟议的研究应提供重要的信息，以提高我们的理解，环境控制的动员。一个创新的教育/推广部分涉及由加州大学洛杉矶分校PI教授的服务学习课程，在此期间，本科生将把有关环境传感器的新信息带到中学（6年级）教室。

CBET-0651968 Jennifer Jay, UCLA (lead)CBET-0651678 Charles Harvey, MITCollaborative Research: Investigation of hydrologic and biogeochemicalcontrols on arsenic mobilization at a field site in Munshiganj, BangladeshThis project will investigate how recently observed phenomena influence arsenic (As) mobilization through deployment of hydrologic and geochemical sensors at a rice paddy site in Bangladesh and through field and laboratory microcosm/mesocosm experiments. Specifically, recent preliminary studies at the site yielded evidence for a gas phase under the plough pan in the soil and also evidence for rapid downward movement of infiltrating water. Trends in geochemical and hydraulic characteristics suggest that diurnal processes, possibly plant-induced, may be important. The project will test the hypothesis that hydrological processes (due to barometric changes and plant evapotranspiration) and plant-induced chemical changes (due to root oxygen release and surface water changes) drive daily oscillations observed at the site. This is a challenging scientific problem, and a comprehensive set of experiments and observations made with an imbedded sensor network will be used to study the problem. The societal impacts of the research are high. Arsenic is a serious pollution problem in the U.S. and globally, and it has had dire health consequences in Bangladesh. The proposed studies should provide important information to improve our understanding of the environmental controls on As mobilization. An innovative educational/outreach component involves a service learning course taught by the UCLA PI, during which undergraduate students will take new information about environmental sensors to middle school (6th grade) classrooms.