Soil Erosion and Vegetation in Grasslands of the Peloncillo Mountains, New Mexico

Abstract

We report soil erosion and vegetation cover in montane desert grassland pastures where livestock grazing had been discontinued at least 5 yr prior to our initial measurements in 1977. Changes in soil surface elevation measured with a precision transit level during a 9‐ to 13‐yr period are compared with changes in vegetation cover and surface hydrological features. We describe changes in soil surface elevation on 10 transects situated on an active hillslope gully system, across two hillslope ravines, and on an intracanyon alluvial landform. Overall we measured a small rate (0.8 mm yr−1) of sediment accumulation across the four study locations. On most slopes, sediment additions were balanced by sediment losses (transportation slopes), or changes in surface elevation along transects were insignificant. A portion of one transect was denudational, with a net loss rate for 12 yr of 3.9 mm yr−1 Another transect accumulated sediments at 6.8 mm yr−1 during an 11‐yr interval. The dynamics of sediment transport are not explained by vegetation cover alone. Rather, cover, slope gradient, ground surface roughness, soil depth, and soil infiltration rates interact to regulate sediment transport during and after storm events. There was no evidence that past livestock grazing affected the measured erosion rates.