Monday, November 5, 2007
19-8

Effect of Urbanization on Heavy Metal Accumulation in Soils of Historical Sanborn Field.

Maryann Kohl and Frieda Eivazi. Cooprative Research Programs, Lincoln University, Jefferson City, MO 65109

Accumulation of heavey metals in soils of urban areas is of a major enviromental concern. This study was undertaken to assess heavey metal concentrations and accumulation in Historical Sanborn Field which was initiated in late 1888 by J.W. Sanborn to demonstrate the value of crop rotations and manure in grain production. Sanborn Field is now located on the campus of University of Missouri at Columbia, Missouri, USA, a rapidly growing metropolitan city. The soil within the study area is a Mexico silt loam (fine, montmorillonitic, mesic Udollic Ochraqualf) which is representative of gently rolling, more erodible soils of the Midwest claypan area. Soil samples from plots no. 6, 7, 17, 18, (continuous corn); 22, and 23 (continuous timothy); 2, 5, 9, 10 (continuous wheat); 25, 26, 27, 28 (rotation, Corn-Wheat-Red Clover) and plot 39 (full fertility, continuous soybean) were collected. Full fertility plots were fertilized based on soil test recommendation and manure was applied at 13.4 Mg/ha. Measurements of temperature and precipitation have been done in Sanborn Field since 1890. Soil samples were taken from 0-10, 10-20, and 20-30 cm depth (after removing the O1 horizon) and processed. The digest was analyzed for the following heavy metals: As, Cd, Cu, Hg, Ni, Pb, and Zn. The soils samples were also analyzed for particle-size distribution, pH, and total C. Results obtained will be presented and the impcact of urbanization on heavy metal distribution as affected by management practices will be discussed.