Review on Dynamics of Soil Erosion and Conservation Efforts in Ethiopia

This paper was aimed to review the spatial and temporal dynamics of soil erosion and conservation efforts being practiced in Ethiopia. In the country, there is highly fluctuating dynamics of soil erosion and its loss rate is large as per the stated international standards. Even if the efforts to conserve soil and water in the country are affected by different factors like agro ecology and the choice of conservation measures, it was practiced since 1970s. Apart from the government’s effort as well as the contribution of different non-governmental organizations in increasing the awareness and understanding towards the impacts of soil erosion, the land tenure system, the existence of poor technology, lack of finance, limited technical support and limited participation of the local community are some of the challenges in Ethiopia restricting the effectiveness of conservation efforts. In addition, the research activities done regarding soil and water conservation in the country are not following integrated and participatory approach. Thus, this makes the efforts regarding research and finding out the best approach for sustainable soil and water conservation practices inefficient. Therefore, promoting integrated and participatory approach as well as linking with income generating business like carbon trading through climate change mitigation is the best options for the expansion and sustainability of soil and water conservation measures in Ethiopia.

Spatial Variation Characteristics of Soil Erodibility in the Yingwugou Watershed of the Middle Dan River, China

Knowledge of soil erodibility (k-value) is vital for measuring soil erosion and conservation planning. Through field sampling, laboratory analysis, and geostatistical analysis, the effects of land use type and soil depth on soil erodibility were studied in a typical watershed of China. The spatial distribution of k-value was determined by Kriging interpolation. Results showed that: (1) soil organic carbon (SOC) content in the study aera is 0.09–150.00 g/kg, and the soil is dominated by silt. The soil erodibility k-values obeyed normal distribution, with an average value of 0.032 t·hm2·h/(MJ·mm·hm2) and a medium degree variation. (2) k-values increased with soil depth. The k-values of surface soil (0–10 cm) for the six different vegetation types ranked in the following order: oak forest > peanut field > grassland > pine forest > tea field > corn field. (3) The theoretical semivariogram model of k-values was a spherical model; k-values in the study area gradually decreased from south to north and east to west, with an obvious banding distribution. Human activities have the greatest effect on k-value such that specific corresponding managements are needed. This could provide scientific and technological support for soil and water conservation measures and comprehensive utilization of the resources.

Soil erosion and conservation in Ethiopia

This paper reviews Ethiopia’s experience and research progress in past soil and water conservation (SWC) efforts and suggests possible solutions for improvement. Although indigenous SWC techniques date back to 400 BC, institutionalized SWC activity in Ethiopia became significant only after the 1970s. At least six national SWC-related programs have been initiated since the 1970s and their focus over time has shifted from food relief to land conservation and then to livelihoods. The overall current soil erosion rates are highly variable and large by international standards, and sheet, rill, and gully erosion are the dominant processes. The influence of human activities on the landscape has traditionally been deleterious, but this trend seems to have recently reversed in some parts of the country following the engagement of the communities in land management. The efficiency of SWC measures show mixed results that are influenced by the type of measures and the agro-ecology under which they were implemented; in general, the relative performance of the interventions is better in the drylands as compared with humid areas. Methodological limitations also occur when addressing the economic aspects related to benefits of ecosystem services and other externalities. Although farmers have shown an increased understanding of the soil erosion problem, SWC efforts face a host of barriers related to limited access to capital, limited benefits, land tenure insecurity, limited technology choices and technical support, and poor community participation. In general SWC research in Ethiopia is fragmented and not comprehensive, mainly because of a lack of participatory research, field observations, and adoptable methods to evaluate impacts. A potentially feasible approach to expand and sustain SWC programs is to attract benefits from global carbon markets. Moreover, a dedicated institution responsible for overseeing the research–extension linkage of SWC interventions of the country should be established.