Effect of grazing on soil-water content in semiarid rangelands of southeast Idaho

• Published in: Journal of arid environments 2011-05, Vol.75 (5), p.464-470
• Main Authors: Weber, K.T., Gokhale, B.S.
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal impact; Animal, plant and microbial ecology; Animals; Biological and medical sciences; capacitance; Capacitance sensor; Decisions; environmental impact; Fundamental and applied biological sciences. Psychology; Grazing; Holistic planned grazing; Litter; Mathematical models; Partial rest; pastures; Rangelands; Rest; Rotational grazing; shrubs; soil associations; soil water content; statistical analysis; stocking rate; Synecology; Terrestrial ecosystems; Vegetation; vegetation cover; Volumetric-water content
• ISSN: 0140-1963; 1095-922X
• DOI: 10.1016/j.jaridenv.2010.12.009

Although numerous factors influence soil-water content, it is considered a key indicator of rangeland health. This paper investigates the effect of grazing on soil-water content using three treatments within the same soil association. The treatments, simulated holistic planned grazing (SHPG), rest-rotation (RESTROT), and total rest (TREST) applied stocking rates of 36, 6, and 0 animal days/hectare respectively. Soil-water content was measured continuously from 2006 to 2008 using 36 capacitance sensors. Statistical analyses revealed differences in percent volumetric-water content (%VWC) and in all treatments, the SHPG pasture had the highest %VWC. Mixed procedures models indicate strong environmental and treatment effects as explanatory variables for the observed difference in %VWC. Although results of vegetation cover analyses indicated no difference in percent shrub cover in the two production pastures (SHPG and RESTROT), percent litter cover differed in the latter years of this study. It was concluded that in addition to a variety of other factors, management decisions (grazing and rest) can have substantial influence upon soil-water content and that soil-water content can vary substantially as a result of animal impact and the duration of grazing. ► Grazing intensity varied from low (6 animal days ha −1) to high (36 animal days ha −1). ► Soil-water content (%VWC) was highest in the holistic planned grazing pasture (HPG). ► HPG used high intensity, short-duration grazing (6 days/year). ► Percent litter cover was also highest under the HPG treatment. ► Soil-water content varies in response to animal impact and the duration of grazing.