SEDIMENT AND CHANNEL DYNAMICS ACROSS A GRADIENT OF GRAZING TREATMENTS IN TALLGRASS PRAIRIE HEADWATER NETWORKS

In the prairie remnants of North America, watershed sediment regimes are heavily influenced by livestock grazing practices. Despite dramatic declines in stream water quality and ecosystem function concomitant with increasing gazing pressures, there have been no studies to quantitatively assess the relationship between various grazing treatments and sediment production in natural grassland ecosystems. In this study, we evaluate suspended sediment transport and channel morphology in the Flint Hills physiographic province using a paired whole-watershed approach, including 2 replicates of high density cattle grazing, 2 replicates of low density cattle grazing, 3 replicates of bison grazing and 3 replicates of no grazing. As expected, results demonstrate that cattle grazing operations increase sediment concentrations and increase channel width. However, no significant differences in suspended sediment dynamics or channel geomorphology were found between bison grazed and ungrazed watersheds.