CBET-0651968 Jennifer Jay, UCLA (lead) CBET-0651678 Charles Harvey, MIT
Collaborative Research: Investigation of hydrologic and biogeochemical controls on arsenic mobilization at a field site in Munshiganj, Bangladesh
This 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.