Soil erosion caused by climate and land-use changes is one of the biggest environmental challenges in highland Ethiopia. The aim of this study was to assess the future soil erosion risks and evaluate the potential conservation measures in the Rib watershed, northwestern highland Ethiopia. We used the HadGEM2-ES model with a moderate greenhouse gas (GHG) concentration scenario (RCP4.5) to project the future climate. The future land-use patterns were predicted using the CA-Markov model. We integrated the RUSLE model with GIS to estimate the spatial distribution of soil loss and identify erosion risk areas. We found that the Rib watershed is highly vulnerable to future climate and land-use changes, leading to a high soil erosion risk. Despite slight growth of forest cover during the study period, the total soil loss for the watershed was estimated to be 7.93 × 10⁶ t year⁻¹ in 2017 and was predicted to increase to 9.75 × 10⁶ t year⁻¹ in 2050, an increase of about 23%. The increase in forest cover was due to the expansion of the area of eucalyptus plantations which are more prone to erosion. Moreover, field survey showed that the residual native forests are sparsely vegetated and mostly used for cattle grazing, increasing the erosion risk even more. In contrast, the combined use of afforestation with native trees and physical soil conservation measures in the upper areas of the catchment could decrease soil loss by 62%. Our results stress the importance of combining soil conservation measures, including converting eucalyptus plantations to native forests, to mitigate the effects of future climate change and increased agricultural production on soil erosion.

中文翻译：

---

气候和土地利用变化下埃塞俄比亚高地的未来土壤流失

由气候和土地利用变化引起的土壤侵蚀是埃塞俄比亚高地面临的最大环境挑战之一。这项研究的目的是评估埃塞俄比亚西北高地Rib流域的未来水土流失风险并评估潜在的保护措施。我们使用具有中等温室气体（GHG）浓度情景（RCP4.5）的HadGEM2-ES模型来预测未来的气候。使用CA-Markov模型预测了未来的土地利用模式。我们将RUSLE模型与GIS集成在一起，以估算土壤流失的空间分布并确定侵蚀风险区域。我们发现，里伯河流域极易受到未来气候和土地利用变化的影响，从而导致很高的土壤侵蚀风险。尽管在研究期间森林覆盖率略有增长，2017年为⁶  t年^-1，预计将增加到9.75×10 ⁶  t年^-1在2050年增长约23％。森林覆盖率的增加归因于桉树种植面积的扩大，而桉树种植园更容易受到侵蚀。此外，野外调查表明，剩余的原始森林是稀疏的植被，主要用于放牧牛群，进一步增加了遭受侵蚀的风险。相比之下，在流域上游地区结合使用绿化和本地树木以及采取物理水土保持措施可将土壤流失减少62％。我们的研究结果强调了结合土壤保护措施（包括将桉树人工林转变为原生林）的重要性，以减轻未来气候变化和农业生产增加对土壤侵蚀的影响。