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Grazing practices affect the soil and vegetation of grasslands, which further influence the provision of ecosystem services and the productivity of grasslands. We determined the ecosystem resilience of a mesic grassland under three grazing management systems in the Pakkies area, (30°33′08″ S, 29°25′22″ E), South Africa: cooperative (continuously grazed since 2017), commercial (rotationally grazed for >20 years), and communal (continuously grazed for >20 years) farms. This was carried out by measuring the penetration resistance and infiltration, soil nutrients, forage quality contents for livestock, veld condition, plant species composition and richness, and functional diversity. The soils had a higher penetration resistance in the continuously grazed communal farm, while water infiltration was highest in the continuously grazed cooperative farm. The plant species and functional diversity were greater in the rotationally grazed commercial farm than in the continuously grazed communal and cooperative farms. The continuously grazed cooperative farm had the highest veld condition score (97%), while the rotationally grazed commercial and the continuously grazed communal farms had 82% and 56% veld condition scores, respectively. The forage quality and soil nutrients were generally similar among all farms. The lower plant diversity observed with continuous grazing may indicate that the ecological system was not as resilient concerning this type of grazing. However, for forage quality, soil nutrients and veld condition, continuous grazing was resilient, which indicates that rotational grazing may not be better than continuous grazing for livestock production in this specific region. As long as a minimum level of ecological resilience can be retained, continuous grazing can sustain effective animal production, particularly for small-holder farmers. [ABSTRACT FROM AUTHOR]

Questions Plant communities fulfil key functions in the ecosystem, which can be characterized by their plant functional traits. In functional ecology, plant communities are considered to hold a set of trait attributes reflecting a specific plant strategy adapted to persist in the environment to which they are exposed. In semi-arid grasslands of the Republic of South Africa, we addressed the following questions: how are community-aggregated plant functional traits ( CPFT) shaped by grazing gradients; which plant strategies are associated with the response of CPFTs; and are environmental factors, such as soil properties and grazing management, interrelated with the functional response of vegetation to grazing gradients? Location Semi-arid grasslands close to Thaba Nchu, Free State ( Republic of South Africa). Methods Piosphere transects from a water point into the field were established to portray grazing gradients on two communal grazing areas with continuous grazing and two commercial farms with rotational grazing. Along each transect, six plots (5 × 5 m) were evenly distributed. The trait-transect sampling was applied to record 12 CPFT related to light capture and forage quality. A redundancy analysis was performed to derive relationship between CPFTs, grazing gradients and environmental conditions. Results Grazing intensity decreased along piosphere transects, from the water point into the field. Most CPFTs responded to this decreasing gradient of grazing intensity and so allowed derivation of trait syndromes that clearly reflect plant strategies of ruderal and competitive vegetation. Close to water points, plants had higher nitrogen concentrations, fewer cell wall components and higher specific leaf area, hence light capture might be faster and more efficient per leaf area and leaf mass. Plant communities exposed to intensive grazing were well adapted to defoliation, trampling and nutrient accumulation through fast growth rates and a quick return strategy. Conclusions In the sacrifice zone around water points, there is an ecological niche for vegetation communities exhibiting a strategy of fast growth, which is well adapted to intense and frequent grazing and is also associated with forage of high nutritional quality. [ABSTRACT FROM AUTHOR]