22nd North American Prairie Conference
Cedar Falls, IA
Half of Iowa’s remnant prairie lies within the Loess Hills of western Iowa, yet development, woody encroachment, and agriculture continue to have an impact upon the size, shape, and quality of grasslands in the region. Given the limited resources available to manage grasslands, prioritizing restoration expenditures and targeting efforts to areas of greatest conservation potential are critical. To this end, we conducted an assessment of landscape patterns in the Loess Hills and developed a conservation priority index (CPI) to identify cropland with the greatest potential to promote connectivity of grasslands. Cropland parcels were given a CPI score between 1 and 100, with high values corresponding to areas having a low corn suitability rating and located close to prairie remnants, and with low values, the reverse. Over the entire Loess Hills landform, croplands dominate, comprising 47% of the land cover, while grasslands, forests, and developed areas comprise 23%, 20%, and 6%, respectively. Cropland patches tend to be contiguous and consist of large, relatively simple shapes, while the patches of remnant prairie are small, fragmented, and far apart. Our analysis also shows that grasslands are more abundant and more connected in the northern half of the Loess Hills. The CPI identified large portions of cropland with low overall agricultural production potential. If cropland areas scoring among the top 30% on the CPI were converted to native prairie, the total amount and connectivity of grasslands in the region would increase substantially, thereby buffering prairie remnants—regionally significant reservoirs of biodiversity—from conservation threats associated with development, woody encroachment, and row-crop agriculture.
Farnsworth, Dustin A.; Schulte, Lisa A.; and Hickey, Susanne, "Evaluation of current and alternative spatial patterns of grassland in the Loess Hills" (2010). Natural Resource Ecology and Management Conference Papers, Posters and Presentations. 13.