In southern Ethiopia wide and deep gullies are common features, significantly affecting farmers' livelihoods. Little action is being taken to address the problem despite farmers being knowledgeable about erosion and its control measures. A study was conduced to investigate the nature and rate of gully development in Umbulo catchment, southern Ethiopia, based on interviews with farmers and field measurements. The results indicated a rapid, down slope development of gullies over the last 30 years with average rate of soil loss from 11 to 30 t ha À1 y À1 . The critical period of development of the gully system was estimated to be between 1974 and 1985, but since then the gully system has enlarged both in depth and width. Wide channels with deep, nearly vertical walls are typical. The trigger for gully initiation is believed to have been human, but the soil properties may have played an important role. Under the current situation agricultural production is unsustainable unless the gullies are controlled using integrated measures at the catchment scale.

No abstract

Soil degradation is evident in the mountainous areas of Ethiopia, is often represented as results of human pressure. It can be improved through different Soil and Water Conservation (SWC) measures. The study was conducted in Goromti watershed, in western Ethiopia to evaluate the impact of Fanya juu structures on some soil physical & chemical properties. Cultivated fields treated by five years and ten years old fanyajuu structures were compared with non conserved cultivated land (control) and evaluated under three slope gradients. The slope gradients were; gentle (3-15%), moderately steep (15-30%) and steep slope (>30%). A total of 27 soil samples were collected from the top 20 cm soil depth replicated three times and selected physical and chemical properties were analysed in the laboratory. The results of the study showed that soil pH, soil organic carbon (SOC), total nitrogen (N) were significantly (p≤0.05) different on farms treated by the fanyajuu compared to the non-conserved plots as well as under the different slope gradients. Bulk density (Db), sand and clay fractions were significantly varied with slope gradient. Soil organic carbon and total N were higher while bulk density was lower in soil under the non-conserved fields than in fields with fanyajuu structures. But no significant difference was observed in soil bulk density, sand and clay fractions among treatments. Similarly, CEC, available K and available P, and exchangeable K + , Ca 2+ , and Mg 2+ didn't show any significant differences with respect to structures and slope gradient. The research indicates that structures could benefit farmers through improving the nutrient status better if integrated with agronomic measures by using vegetation suitable for the local environment in one hand, and properly maintained for longer period of time, on the other.

Soil quality assessment is valuable for evaluating agroecosystem sustainability, soil degradation, and identifying sustainable land management practices. This study compared soil quality within culturally protected forest areas and adjacent grassland, grazing land, and farmland in Abo-Wonsho, Southern Ethiopia. A total of 40 soil samples (4 land uses × 5 replications × 2 soil depth layers: 0 to 10 cm and 10 to 20 cm) were collected for analysis. Soil textural fractions (i.e., sand, silt, and clay percentage) varied with land use and soil depths even though the textural class across all land use types was sandy loam. Bulk density, soil organic carbon (SOC), and available potassium (K) varied significantly: = 0.041, = 0.001, and < 0.001, respectively, with land use and soil depth, but other indicators showed no significant difference. We conclude soil quality can be protected and maintained by improving existing land use practices within both agricultural and modern forest management areas.