Documented increases in woody plant abundance worldwide can reduce land value and grazing capacity. Throughout many grasslands and savannas in South Africa, Seriphium plumosum, an encroaching woody plant, has been rapidly displacing desirable native species. Cost-effective management techniques are required, in order to prevent encroachment. However, the effects of fire and grazing on S. plumosum are not well understood. We established a full factorial, completely randomised experiment to evaluate interactive effects of fire and livestock grazing on woody plant density and native plant diversity. Sixteen 100 m2 plots were aggregated within an area of rangeland and randomly assigned four treatments, including: i) ungrazed, not burned: ii) ungrazed, burned, iii) grazed, not burned, and iv) grazed, burned. Results indicate fire can reduce S. plumosum height (p < 0.01) and canopy cover (p < 0.01), while simultaneously maintaining the herbaceous community composition (p = 0.33). However, this treatment effect was not significant 24 months after a single treatment. This suggests that although fire holds promise for S. plumosum management, follow-up treatments are necessary to control the shrub. Additional research into the effects of altering components of the fire regime in combination with grazing could provide insight into more effective management.

中文翻译：

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南非酸性灌木丛中规定的火和牲畜放牧对Seriphium pumposum的交互作用

世界范围内木本植物丰度的增加会降低土地价值和放牧能力。在南非的许多草原和稀树草原上，一种侵入性的木本植物 Seriphium plumosum 已经迅速取代了理想的本地物种。需要具有成本效益的管理技术，以防止侵占。然而，火和放牧对 S.plomosum 的影响尚不清楚。我们建立了一个全因子、完全随机的实验来评估火和牲畜放牧对木本植物密度和本地植物多样性的交互影响。16 个 100 m2 地块聚集在牧场区域内，随机分配四个处理，包括：i) 未放牧，未烧毁：ii) 未放牧，烧毁，iii) 放牧，未烧毁，和 iv) 放牧，烧毁。结果表明火可以减少 S。羽毛高度 (p < 0.01) 和冠层盖度 (p < 0.01)，同时保持草本群落组成 (p = 0.33)。然而，这种治疗效果在单次治疗后 24 个月并不显着。这表明，虽然火对 S.plomosum 管理有希望，但需要后续处理来控制灌木。对改变火势成分与放牧相结合的影响的进一步研究可以为更有效的管理提供见解。需要进行后续处理以控制灌木。对改变火势成分与放牧相结合的影响的进一步研究可以为更有效的管理提供见解。需要进行后续处理以控制灌木。对改变火势成分与放牧相结合的影响的进一步研究可以为更有效的管理提供见解。