• Soil, Vegetation, and Hydrologic Responses to Grazing Management at Fort Stanton, New Mexico

      Gamougoun, N. D.; Smith, R. P.; Wood, M. K.; Pieper, R. D. (Society for Range Management, 1984-11-01)
      The purpose of this study was to evaluate vegetation, soils, infiltration rates, and sediment production as they relate to livestock exclusion, continuous heavy grazing, continuous moderate grazing, and rotation grazing on a homogeneous plant-soil complex. The exclusion of livestock resulted in infiltration rates significantly higher than when the pastures were grazed in any system. No differences were found between heavily and moderately stocked pastures. This was attributed to organic matter additions from forbs that replaced grasses when the area was heavily grazed. The rotation treatment had infiltration rates that were lower than the exclosures or continuous grazing treatments. Sediment production from interrill erosion was similar in all treatments except when the livestock were concentrated into a fourth of the rotation system's area, which resulted in higher sediment levels.
    • Variability of Infiltration within Large Runoff Plots on Rangelands

      Devaurs, M.; Gifford, G. F. (Society for Range Management, 1984-11-01)
      In this study we investigated the variability of infiltration on native rangeland sites. A rainfall simulator was used to collect data on runoff from small (0.37 m2) plots located within large plot boundaries (32.5 m2). Three range sites were sampled and data were collected from unfenced, fenced, and rototilled conditions on each site. In addition data were collected on vegetation, antecedent moisture, bulk density, soil texture, and organic matter as possible explanations for variations in hydrologic response on small and large plots. The field study demonstrated large variability in measured infiltration and soil physical properties on relatively uniform rangeland sites, suggesting that inherent variability patterns need to be examined to provide appropriate confidence intervals for single parameter values that may be applied to larger areas. No set of factors consistently explained the observed variability within large plots.