TITLE:
Rangeland Degradation Impacts on Vegetation Cover, Soil Properties and Ecosystem Functioning in an Arid and Semi-Arid Climate, South Africa
AUTHORS:
Hermias Cornelius van der Westhuizen, Christiaan Cornelius du Preez, Hendrik Andries Snyman
KEYWORDS:
Rangeland Condition, Soil Degradation, Effective Soil Depth, Soil Erosion, Soil Compaction, Ecosystem Functioning
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.10 No.2,
February
14,
2022
ABSTRACT: The
negative effect of soil erosion and soil compaction is well documented for the
purpose of optimum rangeland functioning, while the impact of rangeland
degradation on effective soil depth is seldom quantified. The aim of this study
was to quantify the response of vegetation cover and soil properties,
particularly effective soil depth and soil texture to rangeland degradation.
Forty-one farms were sampled in the arid and semi-arid climate of South Africa.
Within these farms, data was collected over a vegetation degradation gradient.
Results showed a significant decline in relative basal cover (94% ± 15% to 39%
± 17%) and soil depth (90% ± 14% to 73% ± 24%) as rangeland degraded. Soil
texture changes over the degradation gradients vary for different homogeneous
vegetation types. Indications regarding the loss of a functioning rangeland
ecosystem were also demonstrated, using objective long-term relations between
rangeland conditions and grazing capacity. The study highlights the importance
of sustainable rangeland management practices to reduce the loss in effective
soil depth and to ensure the sustainable utilization of the rangeland
ecosystem. These results can probably extrapolate to other arid and semi-arid
rangelands worldwide.