Soil Landscape and Erosion Relationships in NW IL Objectives To establish the relationship between soil taxonomic description landscape form and position and erosion in an open cultivated watershed in NW IL To determine the effects of landscape components on the soil properties and taxonomic placement of these cultivated hillslope soils when compared with uncultivated and uneroded sites 1 Results A detailed geomorphic map with units based on slope shape gradient and USDA erosion class was prepared Erosion classes were determined for transect pedons by comparing with two uneroded and uncultivated pedons in area cemeteries with similar slope gradients slope shapes slope lengths and landscape positions Results con t Results con t Transect data for all hillslope geomorphic units at the cultivated site showed the shoulders to be either slightly eroded or moderately eroded The lower backslopes and upper footslopes were either severely or very severely eroded suggesting slope length is a significant factor affecting erosion Concave across slope shapes were found to be less eroded than those with convex across slope shapes Suspect some sediments are collecting in concave positions As a result of cultivation and erosion A horizon thickness decreased organic C content decreased and clay content increased as a consequence of cultivation and erosion Results con t Fly ash as a time marker All cultivated pedons failed to meet the mollic epipedon criteria for Mollisols Cemetery pedons still meet the criteria for Mollisols Cultivated and eroded soils now qualify as Alfisols Cultivation and erosion of Mollisols effect the soil taxonomic placement Objectives To develop a method to identify and characterize fly ash content with depth in selected Illinois soils To determine fly ash incidence in soils near to and remote from fly ash sources 2 Natural versus accelerated erosion and sediment deposition 3 Results Results Fly ash spheres are present in large amounts in soils near a source These air borne spheres have been deposited on soils since the 1850s in central Illinois Fly ash spheres presence can be used to identify sediments accumulated since European settlement Fly ash spheres are silt size and have magnetic properties which can be used to separate from non magnetic soil fraction Fly ash has a unique spherical shape which can be used to differentiate from other natural occurring magnetic minerals Quantification of Post settlement Deposition in Sediment Basin Quantification of Post settlement Deposition in Sediment Basin Determine if the top of the buried Ap horizon in a sediment basin was the pre settlement surface Measure the extent of post settlement sedimentation in single outlet sediment basin Estimate the post settlement sediment delivery to the stream and total sediment removed from the surrounding watershed hillslopes using the average sedimentdelivery ratios for watershed of similar size or with a similar soils Attempt to determine the nature of sediment delivery to a sediment basin A horizon thickness cm R cemetery sites versus cultivated sites 4 Depth to C horizon R Cemetery cites verses cultivated sites LC 5
View Full Document
Unlocking...