Impact of Foot Traffic from Military Training on Soil and Vegetation Properties.

The impact of military training activities (primarily foot traffic) on soils and vegetation was assessed at the United States Air Force Academy, Colorado, USA. 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)). Mean infiltration rates on the high use site (0.63 cm/min) and moderate use site (0.67 cm/min) were significantly different from the infiltration rate on the reference site (3.83 cm/min). Soil water holding capacities of the three sites were not significantly different. Descriptive comparisons of total aboveground biomass and litter indicated a 68% decrease in total aboveground biomass and a 91% decrease in litter when the high-use site was compared to the reference site. Using the Universal Soil Loss Equation, an estimated soil erosion rate for the reference plot (0.07 tons/ha/yr) was 30 times less than the erosion rate for the high use plot in the center of the basic cadet training encampment area (2 tons/ha/yr) and between 7 and 6 times less than the moderate use plot and the high use plot on the edge of the encampment area (0.5 and 0.4 tons/ha/yr, respectively). Therefore, training use appears to adversely affect bulk density, infiltration, total aboveground biomass, litter, and erosion. Without implementation of restoration practices, further site degradation is likely.