Soil erosion estimation and erosion risk area prioritization using GIS-based RUSLE model and identification of conservation strategies in Jejebe watershed, Southwestern Ethiopia.

Erosion of soil refers to the process of detaching and transporting topsoil from the land surface by natural forces such as water, wind, and other factors. As a result of this process, soil fertility is lost, water bodies' depth is reduced, water turbidity rises, and flood hazard problems, etc. Using a numerical model of erosion rates and erosion risks in the Jejebe watershed of the Baro Akobo basin in western Ethiopia, this study mapped erosion risks to prioritize conservation measures. In this study, the Revised Universal Soil Loss Equation (RUSLE) model was used, which was adapted to Ethiopian conditions. To estimate soil loss with RUSLE, the rainfall erosivity (R) factor was generated by interpolating rainfall data, the soil erodibility (K) factor was derived from the soil map, the topography (LS) factor was determined from the digital elevation model (DEM), cover and management (C) factor derived from the land use/cover data, and conservation practices (P) factor generated from digital elevation model (DEM) and land use/cover data were integrated with remote sensing data and the GIS 10.5 environment. The findings indicated that the watershed annual soil loss varies from nearly 0 on a gentle slope of forest lands to 265.8 t ha-1 year-1 in the very steep slope upper part of the watershed, with a mean annual soil loss of 36.2 t ha-1 year-1. The total annual soil loss in the watershed is estimated to be around 919,886.5 tons per year. To minimize the amount of soil erosion in the watershed that had been most severely affected, we identified eight conservation strategies that could be implemented. These strategies were based on the participatory watershed development (PWD) principles established by the Ethiopian government and the severity of the erosion in the watershed. The study's findings showed that a GIS-based RUSLE soil erosion assessment model can provide a realistic prediction of the amount of soil loss that will occur in the watershed. This tool can also help identify the priority areas for implementing effective erosion control measures.

Evaluation of the sustainability of existing rainwater harvesting ponds: A case study of Lay Gayint District, South Gondar zone, Ethiopia.

In most of the water-scarce areas, rainwater harvesting (RWH) ponds are essential for meeting the stress of water for various purposes. Besides the performance and sustainability of those rainwater harvesting ponds were not evaluated. This study aimed to evaluate the sustainability of existing rainwater harvesting ponds in Lay Gayint District, Ethiopia. The specific objectives of this study were; (1) to assess the perception of farmers on the potential of RWH ponds, and (2) to identify factors influencing the sustainability of RWH ponds. The demographic characteristics of farm households; farmers' perception about RWH ponds; and the socio-economic conditions of households were collected using household surveys and focused group discussions. The collected data was analyzed through quantitative and qualitative data analysis methods. The results of this study revealed that almost all farmers did not have good perceptions of ponds and had not gained enough awareness of the advantages of ponds. The utilization of the ponds was surrounded by constraints like poor quality and short lifetime of the constructed ponds; low involvement of farmers within the construction of ponds; and wrong-site selection. The incidence of local disputes among the farmers was the most important impact that un-utilized ponds have exerted on the community. About 78 % of the ponds were found in a failed state and 75 % of the ponds have no fences. The construction of RWH ponds in rural districts was based on a quota system which resulted in low sustainability. About 72.2 % of the respondents have not participated in the construction of RWH ponds, on the other hand, 81.5 % didn't get any training about RWH. The majority of the respondents replied that they have no money for constructing and maintaining their ponds. Due to the different factors most of the RWH ponds didn't store and serve for the designed service period which failed to satisfy the water demand. The government shall give attention to the sustainability of ponds by facilitating the involvement of Non-Governmental Organizations (NGOs) in capacity building, technical and financial support.