In the Upper Abbay Basin, renowned as the cradle of the Blue Nile, an unprecedented scientific endeavor has sought to peer five decades into the future of soil health under Ethiopia’s shifting climate. Groundbreaking research led by Wuletawu Abera, Amsalu Tilaye, Degefie Tibebe, and Assefa Abegaz models the trajectories of soil organic carbon (SOC) within croplands—critical reservoirs of fertility that sustain agricultural productivity and ecosystem resilience. By employing the RothC model alongside detailed climatic and land use data, their study sketches a nuanced narrative of soil fate, revealing the fragile balance between regenerative agricultural practices and the inexorable pressures of climate change.
Soil organic carbon, often invisible yet immensely valuable, functions as the bedrock of terrestrial ecosystems. It enhances water retention, strengthens soil structure, and stimulates microbial activity, all culminating in more stable and productive farmlands. For subsistence farmers in Ethiopia’s agropastoral communities, maintaining SOC translates into reduced vulnerability to climate-induced shocks—a safeguard ensuring that harvests can feed families even during adverse conditions. However, decades of deforestation, overgrazing, and the diversion of crop residues for fuel and fodder have critically depleted this vital carbon pool, placing the land on a precarious trajectory.
The specter of climate change adds layers of complexity. Projections indicate a temperature increase of approximately 2.2 degrees Celsius by the year 2070, accompanied by more erratic and diminished rainfall patterns. Elevated temperatures accelerate the microbial decomposition of organic matter, thereby hastening the loss of soil carbon stocks. Consequently, soils face a faster rate of carbon expenditure than replenishment—a dynamic that threatens to erode agricultural productivity and exacerbate food insecurity in an already vulnerable region.
Capturing the intricacies of SOC dynamics across the heterogeneous Upper Abbay landscape through field measurements would be an insurmountable challenge. To overcome this, the researchers utilized RothC, a process-based soil carbon model, effectively creating a “digital twin” of the soil environment. By inputting climate data, soil properties, cropping patterns, and organic matter inputs, the model computed simulations over a fifty-year horizon with high spatial resolution. This approach accounted for the basin’s diverse climatic zones and land use mosaics, linking biophysical processes with human practices.
Eight scenarios were explored within this virtual framework: encompassing combinations of current versus projected climate regimes, alongside varying intensities of regenerative farming practices. These regenerative approaches include the retention of crop residues on fields, increased application of organic manure, the sowing of cover crops, and the integration of agroforestry systems. This comprehensive modeling effort illuminated the future of soil carbon stocks under both business-as-usual and ambitious intervention scenarios, capturing the spatial and temporal variability of outcomes.
Importantly, the study highlights that regenerative agriculture requires considerable labor and social organization. The physical acts of collecting, hauling, and applying crop residues or manure, establishing cover crops, and managing agroforestry demand coordinated communal effort, often disproportionately borne by women. Collective decision-making regarding grazing schedules, manure storage, and seed purchasing underscores the socio-political dimensions embedded in soil management strategies.
One of the pivotal findings reveals a startling geographic divergence in potential benefits. In wetter western parts of the basin, soils exhibit considerable capacity to sequester carbon—potentially accruing up to 13 tonnes of SOC per hectare over fifty years under the most optimistic management regimes and stable climate conditions. Conversely, in the drier eastern zones, climate stressors severely curtail such gains, with certain areas projected to continue losing soil carbon despite best efforts. This spatial heterogeneity suggests that policy and investment strategies must be finely tuned to local contexts rather than relying on blanket solutions.
Climate change emerges as a formidable disruptor, halving potential SOC accumulation even with intensified regenerative practices. In some scenarios, warming and aridity lead to net carbon losses, destabilizing soil health and undermining resilience. These insights underscore that while improved land management can counter degradation, climate impacts impose hard limits that require adaptive prioritization and innovation.
Crucially, the research recognizes the everyday dilemmas faced by smallholder farmers. Choices between using valuable straw as livestock feed, fuelwood for cooking, or leaving it to replenish soils epitomize the trade-offs between immediate subsistence needs and long-term ecological stewardship. These decisions occur against a backdrop of energy scarcity and socio-economic constraints, illustrating that technical solutions must integrate developmental dimensions.
The authors emphasize that transitioning toward sustainable, regenerative agriculture is as much a social challenge as a scientific one. Enabling conditions—including access to alternative energy sources to reduce biomass competition, formation of cooperatives to manage manure and cover crops, and robust carbon financing mechanisms to compensate labor inputs—are essential for translating model scenarios into real impacts on the ground. Without such institutional support, ambitious soil carbon restoration will likely remain aspirational rather than operational.
The study concludes by offering a pragmatic roadmap for action. Immediate priorities focus on securing crop residues, improving manure conservation, and establishing local grazing regulations—relatively low-hanging fruit with substantial yield in SOC retention. These community-driven steps lay the groundwork for later scaling, incorporating cover crops, legumes, and agroforestry to amplify sequestration and resilience. Recognizing and alleviating the disproportionate burden on women through supportive policies and resource allocation is identified as a moral imperative for an equitable agricultural transition.
Local governance and extension services are positioned as critical actors to target and tailor interventions geographically, investing heavily in zones with the highest sequestration potential and providing adaptive management tools elsewhere. Meanwhile, donor agencies and climate finance entities have pivotal roles in catalyzing investment by incentivizing carbon storage outcomes and subsidizing labor and input costs, bridging the gap between model projections and on-the-ground realities.
In sum, while climate change poses severe constraints, this comprehensive, spatially explicit modeling study signals that Ethiopian soils can regain their foundational role in supporting resilient agriculture and rural livelihoods. Achieving this will require an integrated approach uniting scientific insight, social innovation, and financial mechanisms. Soil carbon, far from being an abstract ecological metric, stands as the linchpin for securing Ethiopia’s agricultural future for millions of farming families confronting an uncertain climate horizon.
Subject of Research: Soil organic carbon dynamics under regenerative agriculture and climate change in Ethiopia’s Upper Abbay Basin
Article Title: Modelling SOC dynamics on cropland under different regenerative agriculture practices and climate change scenario using RothC model in the Abbay basin of Ethiopia
News Publication Date: October 1, 2025
Web References:
https://www.sciencedirect.com/science/article/pii/S2665972725003782
References:
DOI: 10.1016/j.indic.2025.100957
Image Credits: Credit: Negesse Mune
Keywords: Soil science, Agriculture, Agroforestry, Climate change
