Congratulations to Joshua McDanel for successfully defending his Masters thesis the week before Thanksgiving! Joshua worked on a collaborative project between the Applied Geomorphology Lab and the Geospatial Laboratory for Soil Informatics in Agronomy. His work focused on mapping the catchments of closed depressions throughout the glaciated upper Midwest using digital soil data in GIS. Prior to the development of artificial drainage infrastructure, these catchments would have been hydrologically isolated from surface water drainage, so we have called them collectively "noncontributing area", or NCA. In general, NCA decreases with increasing drainage density, or the length of streams per unit area. We therefore hypothesized that NCA disappears with time in recently-glaciated landscapes, and Joshua combined his NCA with a simplified map he produced of glacial landscape age to test that hypothesis. His results suggested that time is an important factor in NCA across the region, but a combination of many other factors like climate regime and soil texture might explain differences across the region better.
Although Joshua is finished with is M.S., he will remain at ISU for the time being, researching soils in the Agronomy Department!