Vegetation changes after 12 years in four private ranches under short-duration and continuous grazing in Chihuahua, Mexico
Date
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
With the objective to evaluate the vegetation changes over 12 years in four ranches under Short-Duration (2 ranches) and Continuous (2 ranches ) grazing systems, a vegetation survey study was conducted in the fall of 1993, 1994, and 2005. Vegetation information was collected related to herbaceous basal cover and shrub aerial cover, grass forage production, and plant density. Vegetation was divided by functional groups to facilitate the analysis. The perennial grasses functional group was the most consistent and reliable functional group over time. Annual grasses and annual and perennial forbs were important in the first year but tended to disappear in later years. Short-Duration grazing had a higher perennial basal cover than the traditional system (P=0.059). However, the magnitude of the decrease was greater in Short-Duration than in Continuous grazing. A difference in forage production was found between grazing systems (P=0.006). Ranches under continuous system had the highest and the lowest production. The presence of Lehmann lovegrass in one of the ranches under Continuous grazing accounted for a large proportion of forage.
A severe drought in 5 out of 12 years affected the response of vegetation, and the effect of grazing system was likely diminished by the drought. Short- Duration stocking rates were greater than those used in Continuous grazing. Nevertheless, due the range condition in the Continuous treatment, the stocking rates were also considered high. The stocking rates and drought conditions affected the vegetation response of the grazing systems evaluated in this study.