University of Saskatchewan
Department of Soil Science
College of Agriculture and Bioresources

Environmental Soil Chemistry

Spectroscopic Studies of Soil Chemical Processes

Chemical reactions that occur at the solid-water interface of soils often control the transport and toxicity of contaminants in natural systems. Understanding the mechanisms by which ions react with soils solids is therefore vital in assessing environmental fate. Detailed understanding of the dynamics of interfacial chemical processes requires advanced molecular-scale spectroscopic and microscopic techniques. For environmental research, a spectroscopic tool must be capable of analyzing samples with normal amounts of water present, at realistic concentrations (typically trace levels), and at ambient pressure. Since soils are a complex matrix of many different solids, a technique must additionally be applicable to heterogeneous mixtures of mineral and organic phases. Synchrotron-based X-ray Absorption Spectroscopy (XAS) can provide useful information about the speciation of contaminants in whole soils under hydrated conditions. Examples of such research includes: