IOWA'S ENVIRONMENTAL SUSTAINABILITY (SOILS AND LANDSCAPES): AN INVESTIGATION OF HEAVY METAL CONTAMINATE TRANSPORT

This preliminary research begins to characterize the interrelationships between Iowa’s landforms and the region’s environmental sustainability (Hallberg et al., 1978; Ruhe, 1969). Our project focuses on 2 primary objectives: 1. Delineating surficial geologic environments (approx. 1:12,000) to provide a geographic context for geochemical investigations and 2. Investigate the development, distribution, and migration of heavy metals (e.g. Cd, As, Pb, Hg, Se and Cr) within Iowa’s glacial sediments and soils. Monitoring Iowa’s changing landscapes as a product of dynamic earth surface processes (e.g. flooding and climatic variability) are issues that are becoming increasingly more important to many groups including: farmers, land-use planners, and government agencies.

We are currently working with the Natural Resources Conservation Service (NRCS) and Iowa Geological and Water Survey (IGWS) to characterize the distribution of Iowa’s glacial sediments and soils. While it is well known that Cd+2 (cadmium) is a highly hazardous environmental pollutant and carcinogen, it is not widely appreciated that soil fertility may also correlate to the naturally occurring concentrations of heavy metals. In addition, a high natural occurrence of Cd or other heavy metals may have the potential to impact the region’s agricultural base though soil to plant nutrient transfer cycles. The scientific significance of this project rests on the fact that heavy metals in the food chain are a major concern to Iowa’s economy and health. Laboratory analyses including clay mineralogy (XRF), heavy metal identification (XRF), and particle-size-analysis of the area’s complex landforms is facilitating the development of baseline/background geologic data. These data are being used to delineate the complex interrelationships between natural and anthropogenic variables that may influence soil development, surficial to groundwater flow, and contaminate transport through Iowa’s landform regions.