Brand, G., B. Vondracek, and N. R. Jordan. Influence of grazing and land use on stream channel characteristics at multiple scales.
Rotational grazing (RG) is a livestock management practice that rotates cattle on a scale of hours to days among small pastures called paddocks; RG may provide beneficial effects on stream channels relative to other livestock management practices, but previous comparisons have been restricted in scale and scope. We evaluated 11 stream channel characteristics on 37 small dairy farms that used either RG or confinement dairy (CD) production methods. Our objectives were to: (1) compare channel characteristics on RG and CD farms in New York, Pennsylvania, and Wisconsin, USA; (2) examine land use on and around these farms that may affect stream channel characteristics. We examined on-farm land use in 50m riparian areas along selected stream reaches, whole-farm land use, and land use in catchments upstream of selected reaches. RG and CD farms did not differ broadly in stream channel characteristics, although modest differences occurred in some areas. Land cover in 50m riparian areas was not different between farm types within states. As expected, whole-farm land use differed significantly between farm types; CD farms allocated more land to annual row crops, whereas RG farms allocated more land to pasture and grassland. Land cover in catchments was not significantly different, demonstrating that the landscape context of RG and CD farms was similar. Our finding that RG farms did not have substantial beneficial effects on stream channel characteristics compared to CD farms accords with a broader comparison of environmental attributes on these study farms, which found only limited beneficial effects of RG on grassland bird abundance and native plant conservation. The biophysical attributes of stream channels differed across study regions. We suggest catchment-wide implementation of RG dairy farming will be needed to achieve substantial improvement in stream channel characteristics from this livestock management practice.