A study on effects of bush encroachment control techniques on rangeland productivity and tick population dynamics was conducted in Arero district of Borana zone, southern Ethiopia, for three consecutive years. The study targeted two main and dominant encroaching bush species in Borana rangeland, Acacia drepanolobium and Acacia mellifera, and their effects on some vegetation attributes and tick population dynamics. A hectare of rangeland encroached by these two acacia species was replicated/divided into three plots, and each plot was subdivided into five sub-plots to receive five treatments: cutting at 0.5 m above ground and pouring kerosene on stumps (T1), cutting at 0.5 m above ground and debarking the stumps down into the soil surface (T2), cutting at 0.5 m above ground alone (T3), cutting at 0.5 m above ground and dissecting the stumps (T4) and control (T5). Data on basal and litter covers, soil erosion and compaction, dead and re-sprouted encroaching tree/shrub species and nymph- and adult-stage tick populations were collected before and after treatment applications. The applied treatments significantly influenced (p < 0.05) basal cover, nymph- and adult-stage tick population and the two encroaching tree species. The results of this study showed that T3 and T2 were good in controlling A. drepanolobium in that order. T4 and T2 had a significant effect in controlling A. mellifera in their order. Controlling bush encroachment had also a positive effect in eradicating the tick population. The most dominant grass and non-grass species observed after the control actions were Cenchrus ciliaris, Chrysopogon aucheri, Abutilon hirtum, Pennisetum mezianum, Dyschoriste hildebrandtii, Zaleya pentandra and Eragrostis papposa. Therefore, controlling encroaching tree/shrub species had created a conducive grazing area with palatable herbaceous species for the livestock and unequivocally reduced tick population which play a role in reducing cattle milk production through closing off teats. The management of bush encroachment, if sustained, will contribute in stabilizing rangelands and help minimize the negative effects of feed and food crises in the future.

Grazing management strategies tend to have different effects on rangeland plant production. Changes in grazing management can, therefore, affect the carbon stock potential of rangelands. Despite rangeland ecosystems being important global sinks for carbon, we know relatively little about the effect of traditional grazing management practices on their potential to store carbon. In this study, we evaluated the carbon stock and change rate of rangelands using three traditional grazing management practices in the semiarid pastoral ecosystem of eastern Ethiopia. By comparing data on vegetation and soil carbon stocks, we found that there was a strong significant difference (p < 0.001) between these different management practices. In particular, the establishment of enclosures was associated with an annual increase in carbon stocks of soil (3%) and woody (11.9%) and herbaceous (57.6%) biomass, when compared to communal open lands. Both enclosure and browsing management practices were found to have the highest levels of soil organic carbon stocks, differing only in terms of the amount of woody and herbaceous biomass. Thus, modest changes in traditional grazing management practices can play an important role in carbon storage and sequestration. Further research is required on a wider range of traditional pastoral management practices across space and time, as understanding these processes is key to combating global climate change.

Understanding the impact of land use change on soil organic carbon stock following the conversion of a semiarid rangeland into different land use types is essential to devise an appropriate and sustainable rangeland management strategy. However, there is a knowledge gap as to the impact of currently ongoing land use changes on soil organic carbon stock, which is an important rangeland ecosystem service, particularly in the face of climate change. Thus, this study was conducted to assess the effect of land use change on soil organic carbon stock in three land use types, namely, enclosures, communal grazing and cultivated lands in Borana rangeland. The result indicated that there were significant interactions between land use types and depths for soil organic carbon stock (p<0.0001) and bulk density (p=0.0055) with mean losses of 60% and 69% in soil organic carbon stock from the surface layer (0-10 cm) of communal and cultivated lands, respectively, as compared to enclosure land use type. The results indicated that communal grazing and crop cultivation in the Borana rangeland resulted in significantly decreased soil organic carbon stock. Hence, the current trend must be curbed to put back the system on its right track of resilience and sustainability for its long-term benefit and to mitigate the unprecedented increase in CO2. Therefore, the results of this study would be useful for the improvement of land use management in the future.

Rangelands contribute to human well-being worldwide. However, its fragile ecosystems are threatened due to inappropriate management that has been leading to its degradation in African rangelands in general and in Ethiopian rangelands in particular. Rangeland degradation is attributable to both natural and anthropogenic causes. Restoring degraded areas by replanting using native species is one of the most promising sustainable rangeland management tools to fight the degradation in the rangelands and enhance resilience in the face of environmental shocks. Restoration improves vegetation cover and biomass yield and enhances other ecosystem services. Native drought-tolerant species have produced promising rehabilitation outcomes and have been recommended for the restoration of degraded rangeland areas. Replanting using native species remains a viable sustainable management option to enhance resilience in the face of environmental shocks. Therefore, to maintain the sustainability and resilient rangeland ecosystems, comprehensive approaches and strategies suitable for rangelands need to be revitalized, developed, strengthened and promoted.