IMPACTS OF LAND-USE ACTIVITIES ON THE PRESENCE AND PERSISTENCE OF TRACE METALS IN SOIL

The natural biogeochemical cycles of soil have been altered by human activities such as the burning of fossil fuels and waste materials, ore mining and smelting, and the agricultural application of fertilizer and sewage sludge. Soil is the medium upon which the interactions of cultural land-use activities and the “natural” environment are imprinted. In soils, trace metals from these activities are particularly problematic as contaminants because of their availability to plants as they uptake soil solution. Studies of the effects of different land-use activities have focused mainly on urban soils where the disturbance of soils from industry and urbanization is greatest, and on agricultural soils impacted by erosion and/or chemical manipulation to maintain/increase soil productivity. Yet little work has been done to document how Midwestern soils have responded to the early stages of historic land-use in extinct rural settlements for various reasons. However, archaeological and pedologic investigations at New Philadelphia, Illinois indicate evidence of past land-use activities preserved beneath the modern plow zone. Presented here are analyses of stratigraphic depth profiles of trace and toxic elements and their relationship to the other indicators of soil productivity (e.g. organic matter content, pH, cation exchange capacity, and specific surface area). These preliminary analyses reveal differential impacts on the biogeochemical processes of soil due to different land-use activities that elucidate the history of the cultural landscapes and agricultural changes that will aid us in understanding sustainability of soil productivity in the future.