Donald L. SparksProfessor

The Environmental Soil Chemistry Laboratory focuses on how toxic metals such as arsenic (As), nickel (Ni), and zinc (Zn) and plant nutrients such as phosphorus (P) and sulfur (S) are bound (sorbed) on soils. We conduct these studies under different environmental and experimental conditions (pH, time, temperature, hydration state, presence of microbes) to best represent the natural environment. We use bright light sources generated at synchrotron facilities (associated with National Laboratories) to determine the forms (species) of the metals and nutrients in the soil at the molecular scale. This information is necessary to make accurate predictions about how easily the contaminant will leach into the water supplies, and determine its toxicity and bioavailability to plants, animals, and humans. We also conduct speciation research on metal contaminated soils and on plants that accumulate large quantities of metals (hyperaccumulators). The results of these studies are useful in developing effective strategies for soil remediation.