Rhizosphere Chemistry and Mineralogy
In this NSF and USDA-funded work, we develop tools and methods to examine the rhizosphere (the zone of soil around roots). This zone has enhanced biological, physical, and chemical activity and is dynamic in space and time, making it a hotspot of biogeochemistry. In rice and other wetland plants, this zone forms a layer of iron oxyhydroxide minerals, or “iron plaque” that acts as a reactive barrier for nutrients like P and contaminants like As. We sample this environment and use conventional and advanced spectroscopic techniques to analyze the rhizosphere, making chemical “maps” of where the elements are located. For some elements like arsenic, we can also use these techniques to “map” the different chemical forms or “species” from the soil to the root and inside of the plant.
Rice Biogeochemistry – Limiting Toxic Metal(loid)s and Methane Emissions
We use pots, outdoor mesocosmos, and field-scale studies to discover ways to lower the concentrations of toxic metal(loid)s like inorganic arsenic and cadmium into rice grain and lower methane emissions. In this NSF and USDA-funded work, we explore how different management (e.g., soil amendments, water manipulations) affect rice biogeochemistry and speciation and localization of arsenic in rice grain. We take a systems approach, ensuring that the proposed management strategies do not have unintended negative outcomes. We also work with farmers to develop on farm tools to better manage arsenic risk.
Coastal Biogeochemistry Across the Terrestrial-Aquatic Interface
Delaware is surrounded by the Chesapeake Bay, the Delaware Bay, and the Atlantic Ocean . Therefore, there are many opportunities to explore biogeochemistry across the terrestrial-aquatic interface. In addition, Delaware is the state with the lowest mean elevation and is on the front lines of sea level rise, affecting upland coastal forests and agricultural systems. We have DOE and NSF-funded projects at several sites across the Delmarva peninsula to explore carbon and nutrient dynamics in these ecosystems.
We are passionate about creating opportunities for young people and underrepresented groups to access science. We do outreach in preK-12 groups including paid internships to high school students and day camps for pre-school and middle school students in the surrounding area, in addition to providing opportunities for undergraduate and graduate students for hands-on research.