Extent of Gully Erosion and Farmer’s Perception of Soil Erosion in Alalicha Watershed, Southern Ethiopia

A study was conducted to investigate the extent and rate of gully erosion in Alalicha watershed, southern Ethiopia. Gully measurements, field observations, and interviewing were used to generate the necessary data. Two sub watersheds; Bora and Banda were delineated and 21 gullies were identified. Investigation of the morphology, age and main causes for initiation of the gullies were carried out. The result shows that, long term gully erosion rate for the watershed was 2.12 t ha-1yr-1 and the total surface area occupied by gullies in Bora and Banda sub watersheds were about 19,328.2 m2 and 6,433.2 m2 respectively. The estimated total volume of soil loss was over 36,000 m3 in Bora and 8,700 m3 in Banda sub watersheds. A gully density of 11.1 m/ha for Bara and 6.7m/ha for Banda were estimated implying variations in severity of gully erosion. Based on length, all the gullies in the watershed have categorized under long gullies; however medium deep gullies dominate (77-88%) in both sub watersheds than shallow gullies (12-23%). Analysis of the gully morphology reveals that, a negative relationship exists between the top width and depth of gully. The damages and associated problems of the gullies, as explained by farmers, include loss of land, dissection of farms, and deposition of sediments on growing crops and restriction of movement of animal and people. The farmers of the watershed were well aware of soil erosion, soil fertility loss and erosion control and fertility management methods. However reluctant to implement as, they look food incentives because of poor economic status. Hence to conserve the land primarily awareness creation and encouraging the farmers through some sort of incentive may be required. Keywords: gully erosion, gully morphology, farmers’ perception and erosion control

Assessing water quality of rural water supply schemes as a measure of service delivery sustainability: A case study of WondoGenet district, Southern Ethiopia

This study was conducted in WondoGenet district, Southern Ethiopia to assess the water quality of rural water supply schemes in relation to the sustainability of their service delivery. 28 functional water  points were selected randomly, for their assessments. The assessments included sanitary surveillance of water points and water quality analyses. Water samples were analyzed for pH, temperature, total  dissolved solids, turbidity, total hardness, fecal and total coliform bacteria, fluoride, chloride, nitrate,  manganese, and iron. The results obtained show that most of the 'user perceived' acceptable drinking  water quality parameters were within the World Health Organization (WHO) guidelines for drinking  water quality, based on aesthetic and taste considerations. Only one dug-well had marginally higher  level of total hardness (that is, 220 mg/l of CaCO3), while four water points had higher turbidity  ranging from 8.3 to 64 NTU when compared with the WHO guidelines. In all the sampled water points,  the level of iron (<0.009 to 1.25 mg/l), manganese (0.10 to 1.50 mg/l), chloride (0.80 to 62.5 mg/l),  and nitrate (0.90 to 12.7 mg/l) were within the WHO guidelines. Fluoride was also found to be below  the WHO health based limit (<1.5 mg/l). However, majority (85.7%) of the water points had  detectable levels of total coliform bacteria (1 to 68 cfu). On the other hand, it was only in 25% of the  water points that fecal coliform bacteria were detected (1 to 10 cfu). This shows that the  bacteriological water quality is of concern as majority of the water points had detectable levels of  coliform bacteria. Therefore, regular chlorination of water points, particularly dug wells, should  continue. Besides, disinfection of water at the household level can be an added advantage.Key words: Ethiopia, quality, rural, supply, sustainability, water

Land Use Effects on Soil Quality Indicators: A Case Study of Abo-Wonsho Southern Ethiopia

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: , , and , 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

A systems model describing the impact of organic resource use on farming households in low to middle income countries

We are grateful for support from the DFID-NERC El Niño programme in project NE P004830, “Building Resilience in Ethiopia’s Awassa region to Drought (BREAD)”, the ESRC NEXUS programme in project IEAS/POO2501/1, “Improving organic resource use in rural Ethiopia (IPORE)”, and the NERC ESPA programme in project NEK0104251 “Alternative carbon investments in ecosystems for poverty alleviation (ALTER)”. We are also grateful to Dr. V.U.M. Rao (Former Project Coordinator, AICRP on Agrometeorology, CRIDA, Hyderabad) and Dr. S.K. Chaudhari (DDG, NRM Division, KAB-II, ICAR, New Delhi) for their assistance in collecting meteorological data of Parbhani, Maharashtra.Peer reviewedPostprin

Treatment of organic resources before soil incorporation in semi-arid regions improves resilience to El Niño, and increases crop production and economic returns

We are grateful for support from the DFID-NERC El Niño programme in project NE P004830, “Building Resilience in Ethiopia’s Awassa region to Drought (BREAD)”, the ESRC NEXUS programme in project IEAS/POO2501/1, “Improving organic resource use in rural Ethiopia (IPORE)”, and the NERC ESPA programme in project NEK0104251 “Alternative carbon investments in ecosystems for poverty alleviation (ALTER)”. We are also grateful to Anke Fischer (James Hutton Insitute) for her comments on the paper.Peer reviewedPublisher PD

Identification of Soil Erosion Hotspots in Jimma Zone (Ethiopia) Using GIS Based Approach

No abstract

The Effects of 'Fanya juu' Soil Conservation Structure on Selected Soil Physical & Chemical Properties: the Case of Goromti Watershed, Western Ethiopia

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

Integrated Modeling of Land Degradation Dynamics and Insights on the Possible Future Management Alternatives in the Gidabo River Basin, Ethiopian Rift Valley

Land degradation is a pivotal environmental concern, bearing substantial impacts in the Gidabo river basin (GRB) in Ethiopia, prompting a critical need for effective mitigation strategies. In this study, we aimed to assess the dynamics of land degradation pathways in the context of change in climate and land use. The identification of potential erosion hotspots and the appraisal of management strategies was also carried out. The Soil and Water Assessment Tool (SWAT) and the Good Practice Guidance (GPG) framework was employed. The results revealed a compelling synergy between land use dynamics and climate changes, asserting joint and individual prevalence in influencing surface runoff and sediment yield. The past simulation revealed 4–5.9% and 24–43% increments in mean annual runoff and sediment yield, respectively. While the near (2021–2040) and mid (2041–2060) future scenarios displayed varying trends under RCP4.5 and RCP8.5. Furthermore, sub-basins prone to soil erosion risk were identified, thereby enabling targeted conservation efforts. The assessment of trends in land degradation neutrality (LDN) unveiled the expansion of land degradation trajectories (by 26%) from 1985–2003 to 2003–2021. This might be attributed to the dynamic interplay between climate and land use land cover (LULC) change, with croplands and bare land emerging as high-risk degraded areas. Addressing these concerns, soil/stone bund, terracing, contour farming, and reforestation practice can significantly reduce the annual sediment yield in the future. The integration of soil erosion indicators with LDN sub-indicators can provide a more comprehensive approach that can lead to more effective land management and restoration strategies to achieve the LDN goal. The findings of this study could contribute crucial insights and substantial implications for policymakers, land managers, and conservationists. Moreover, future efforts should be directed to expand investigations into diverse land degradation pathways and mitigation measures

Effects of Climate Variability on Normalized Difference Vegetation Index (NDVI) in the Gojeb River Catchment, Omo-Gibe Basin, Ethiopia

Vegetation dynamics have been visibly influenced by climate variability. The Normalized Difference Vegetation Index (NDVI) has been the most commonly used index in vegetation dynamics. The study was conducted to examine the effects of climatic variability (rainfall) on NDVI for the periods 1982–2015 in the Gojeb River Catchment (GRC), Omo-Gibe Basin, Ethiopia. The spatiotemporal trend in NDVI and rainfall time series was assessed using a Theil–Sen (Sen) slope and Mann–Kendall (MK) statistical significance test at a 95% confidence interval. Moreover, the residual trend analysis (RESTREND) method was used to investigate the effect of rainfall and human induction on vegetation degradation. The Sen’s slope trend analysis and MK significant test indicated that the magnitude of annual NDVI and rainfall showed significant decrement and/or increment in various portions of the GRC. The concurrent decrement and/or increment of annual NDVI and rainfall distributions both spatially and temporarily could be attributed to the significant positive correlation of the monthly (RNDVI-RF = 0.189, P≤0.001) and annual (RNDVI-RF = 0.637, P≤0.001) NDVI with rainfall in almost all portions of the catchment. In the GRC, a strongly negative decrement and strong positive increment of NDVI could be derived by human-induced and rainfall variability, respectively. Accordingly, the significant NDVI decrement in the downstream portion and significant increment in the northern portion of the catchment could be attributed to human-induced vegetation degradation and the variability of rainfall, respectively. The dominance of a decreasing trend in the residuals at the pixel level for the NDVI from 1982, 1984, 2000, 2008 to 2012 indicates vegetation degradation. The strong upward trend in the residuals evident from 1983, 1991, 1998 to 2007 was indicative of vegetation improvements. In the GRC, the residuals may be derived from climatic variations (mainly rainfall) and human activities. The time lag between NDVI and climate factors (rainfall) varied mainly from two to three months. In the study catchment, since vegetation degradations are mainly caused by human induction and rainfall variability, integrated and sustainable landscape management and climate-smart agricultural practices could have paramount importance in reversing the degradation processes