To assess the trends in, and impacts of cattle grazing on, both vegetation composition and ground cover in two major subalpine plant communities--grassland and open heathland--within the permanent plots established in the 1940s on the Bogong High Plains' (pp. 607-608)
Type of Study:
In... grassland plots, established in 1946, cattle grazing has prevented the large-scale regeneration of a number of tall, palatable forbs and short, palatable shrubs, while in the absence of grazing, the cover of these life forms increased substantially. The amount of bare ground and loose litter was significantly greater on the grazed compared with the ungrazed plot...The current condition of grazed grassland on the Bogong High Plains is interpreted as stable, yet degraded. Improvement in condition will occur in the absence of grazing....There was no evidence that grazing has reduced shrub cover...in open heathland (pp. 607).
Plots have varying locality, vegetation type (grassland or open heathland), grazing status (grazed or ungrazed).
Alpine and subalpine vegetation is slow to recover from disturbance, and the rate of recovery is unquestionably slower in areas grazed by cattle. In grassland, continued grazing will reduce the abundance of taller forbs and dwarf, palatable shrubs; some shrubs... may continue to expand. Livestock grazing "will therefore not reduce the risk of fire in such communities" (pp. 632-633).
Frequentist (P values): single factor, repeated measures ANOVA; linear and quadratic polynomial regressions.
Comprehensive analysis of long term vegetation change in grassland and open heathlandbased on plots established on the Bogong High Plains in the 1940s. Clear demonstration of the landscape consequences of selective livestock grazing in Australian alpine environments.
Imogen Fraser; Dick Williams
Bogong High Plains, Australian Alpine National Park, Victoria, Australia
Response variable :
Species compostion and cover, shrub age (based on ring counts), and the height, canopy diameter and stem diameter of shrubs.
18–50 points per transect; 10–44 transects per site.
Alpine grassland and open heathland.
0.45–0.15 ha of plots at each site, 6 sites over approximately 55 ha.
Wahren C.H.A., Papst W.A., Williams R.J. (1994) Long-term vegetation change in relation to cattle grazing in subalpine grassland and heathland on the Bogong High Plains: an analysis of vegetation records from 1945 to 1994. Australian Journal of Botany 42, 607–639.