摘要: |
Soils and vegetation are subjected to stress and disturbance under human foot traffic. This study was conducted to determine whether training at the U.S. Air Force Academy adversely impacted soils and vegetation. In the summer of 1998, the effects of training on bulk density, infiltration, soil water holding capacity, soil total C and N concentrations, soil C:N ratio, total above ground biomass, and litter layer were comparatively studied at the Academy's Jack's Valley Training Area. In May-June 1998 after 2 years of intensive training use, mean bulk densities of the top 6 cm of soil in the high use site (1.37 g cm-3) and moderate use site (1.30 g cm-3) were significantly different from bulk density of the reference site (1.04 g cm- 3). Descriptive comparisons of the total aboveground biomass and litter showed a 68 percent decrease in total aboveground biomass and 91 percent decrease in litter when the high use site was compared to the low use site. Therefore, training use appears to adversely affect bulk density, infiltration, total aboveground biomass, and litter. Without restoration, previous research indicates that sites with increased bulk densities, decreased infiltration, and decreased total aboveground biomass and litter would be subject to increased soil erosion. |