Your search found 8 records
1 Drechsel, Pay; Heffer, P.; Magen, H.; Mikkelsen, R.; Wichelns, D. (Eds.) 2015. Managing water and fertilizer for sustainable agricultural intensification. 1st ed. Paris, France: International Fertilizer Industry Association (IFA); Colombo, Sri Lanka: International Water Management Institute (IWMI); Georgia, USA: International Plant Nutrition Institute (IPNI); Horgen, Switzerland: International Potash Institute (IPI). 270p.
(Location: IWMI HQ Call no: IWMI Record No: H046805)
(13.13 MB)
(Location: IWMI HQ Call no: e-copy only Record No: H048197)
(0.59 MB)
Improved soil and water management practices can reduce moisture stress and crop failures associated with rain-fed cropping systems. Little information exists on soil and water management technologies requirements for male and female farmers in different agro-ecological regions. The objective of current study was to investigate farmers’ sources of information and perceptions on soil and water management technologies. Four sites selected from different agro-ecological regions (AERs), sub-humid (Mazowe/Goromonzi, and Kadoma) and semi-arid (Matobo and Chiredzi). Data on sources of information on soil and water management, types of technologies preferred by farmers and constraints to adoption of technologies were collected through household interviews and focus group discussions. Results showed that government extension agents, farmer-to farmer extension and non-governmental organizations were the main sources of information on soil and water management technologies at all the sites. NGOs mainly provide information on reduced tillage methods. Main technologies were mulching (61%), reduced tillage methods (53%), and contour ridges (33%) in Mazowe/Goromonzi district, reduced tillage method (83) and mulching (64%) in Kadoma, and reduced tillage methods (54%) and contour ridges (47%) in Matobo. More farmers used soil and water management technologies at the sub-humid sites than at the semi-arid sites. Soil and water conservation technologies used were similar between male-headed (MHH) and female-headed households (FHH). Soil and water conservation technologies used by farmers matched their preferences in two of the four study sites. The findings are important for targeting soil and water management practices in the various agro-ecological zones.
(Location: IWMI HQ Call no: e-copy only Record No: H048463)
Land use and management affects runoff and soil loss from a catchment. The present study investigated the effects of land use on runoff and suspended sediment concentration and yield in the northwestern Ethiopia. We selected two small catchments: cultivated land and grassland dominated catchments within the 95 ha Debre Mawi catchment. Hydrometric and sediment concentration data were collected for five years (i.e., 2010–2014). Significant (p < 0.05) differences in daily, monthly and annual runoff, as well as suspended sediment concentrations were observed between cultivated land and grassland dominated catchments. The greater runoff, suspended sediment concentration and yield in the cultivated catchment could be attributed to repeated tillage and low soil organic matter. Repeated tillage in the cultivated land lead to soil disturbance and the low organic matter lead to aggregate instability, both of which consequently increase the detachment of soil particles and transport by generated runoff. Our results support that land management practices that involve lower soil disturbance and increase ground cover on degraded highland areas such as the Ethiopian highlands could help reduce runoff and soil loss.
4 Sishu, F. K.; Thegaye, E. K.; Schmitter, Petra; Habtu, N. G.; Tilahun, S. A.; Steenhuis, T. S. 2020. Endosulfan pesticide dissipation and residue levels in khat and onion in a sub-humid region of Ethiopia. In Habtu, N. G.; Ayele, D. W.; Fanta, S. W.; Admasu, B. T.; Bitew, M. A. (Eds.). Advances of science and technology. Proceedings of the 7th EAI International Conference on Advancement of Science and Technology (ICAST 2019), Bahir Dar, Ethiopia, 2-4 August 2019. Cham, Switzerland: Springer. pp.16-28. (Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering (LNICST) Volume 308) [doi: https://doi.org/10.1007/978-3-030-43690-2_2]
(Location: IWMI HQ Call no: e-copy only Record No: H049711)
(0.86 MB)
Endosulfan, a mixture of a- and ß-isomers, is used by farmers in the wet and dry season for khat and onion production. Khat leaf samples were collected in farmer fields at intervals of 1 h; 1, 5, 9 and 14 d after application. The dissipation rate of a- and ß-isomers and residue level in khat were compared with residue levels in onion. The extraction was done by using Quick Easy Cheap Effective Rugged and Safe (QuEChERS) method and analyzed by Gas Chromatography – Electron Capture Detector (GC-ECD). Greater residue a- and ß-isomer endosulfan levels were found in khat compared to onion as khat leaves are sprayed repeatedly in two week. Residue levels of khat exceeded the tolerable EU limit of 0.05 mg.kg-1 for leafy vegetables and herbs. For both raw and processed onion sample a- and ßendosulfan residues level were below the tolerable of limit EU regulation for bulb vegetables (i.e. 0. 1 mg.kg-1). The mean half-life for the a-isomer of endosulfan was 3.4 d in the wet season and 3.6 d in the dry season whilst that for the ß-isomer was 5.0 d and 5.4 d respectively. Both isomers dissipated fastest in the wet season under conditions of high humidity and precipitation. The ß-isomer persisted longer and had a lower dissipation rate from plants surface compared to the a-isomer.
(Location: IWMI HQ Call no: e-copy only Record No: H049935)
(1.65 MB)
Land resources in developing countries are facing intense degradation due to deforestation and subsequent loss of organic matter from continuous tillage that causes soil erosion and gulley formation. The Ethiopian highlands are especially and severely affected. One of the land and water management practices to counteract this problem, fenced areas to prevent livestock access (called exclosures), has been in practice for the last few decades in the semi-arid highlands of Ethiopia but its effect on degraded landscapes has not been well researched – especially in the sub-humid and humid highlands. The aim of this study is to evaluate the effects of exclosures on improving degraded landscapes in the sub-humid highlands. The research was carried out in the Ferenj Wuha watershed, in the northwestern sub-humid Ethiopian highlands, where land and water management practices were implemented starting in 2011. Vegetation was inventoried and aboveground biomass, carbon and nutrient stock determined for communal grazing land, exclosures and for other uses. In addition, soil samples were collected for nutrient analysis. Our results show that exclosures have a richer and more diverse set of plant species compared to communal grazing land. Establishment of an exclosure also enhanced organic carbon, total nitrogen and available phosphorus. Over a six-year period, aboveground biomass increased by 54 Mg ha 1 (or 81%) at the watershed scale because of the conversion of communal grazing land to exclosures. The improvement in soil nutrients due to exclosures, in turn, increased carbon and nutrient stock. The results support regeneration of degraded landscapes by restoring vegetation, soil fertility, carbon and nutrient stocks in the Northwestern highlands of Ethiopia. However, additional research is required to more accurately quantify these improvements because current research efforts that sample only the surface soils seem to indicate that the capacity of exclosures to increase soil carbon storage is decreasing when annual rainfall is increasing.
(Location: IWMI HQ Call no: e-copy only Record No: H049936)
(2.29 MB)
Gullies that are expanding at alarming rate are responsible for the majority of soil losses in the (sub) humid highlands of Ethiopia. Few affordable and effective methods for gully erosion control are available in the highlands. The objective of the study was to develop cost-effective measures to halt gully expansion by determining stable-bank conditions under a variety of environmental situations using the Bank Stability and Toe Erosion Model (BSTEM). The study was carried out in the sub humid Debre Mawi watershed, located 30 km south of Lake Tana. Input data for the BSTEM model were collected using field surveys and soil sampling. After the BSTEM was tested on actual measured soil data, soil cohesion and internal friction angle were calibrated against observed gully bank retreat. Using the calibrated parameters, the model evaluated the stabilization of the existing gully bank under different scenarios in which groundwater table, bank angle and bank height, tension crack depth, vegetation, and toe protection were varied. Finally, the head-cut of the study gully was treated based on the model recommendation. The simulated results showed that a 5 m deep gully was stable under fully saturated conditions when the bank toe is protected, its upper surface is vegetated, and its bank angles do not exceed 45°. If the depth of the gully is less than 5 m or if its water table is deeper than 0.5 m, only regrading the gully bank to an angle of 45° can stabilize the gully. BSTEM showed to be an effective tool that can be used to evaluate gully control measures.
(Location: IWMI HQ Call no: e-copy only Record No: H050402)
(7.40 MB) (7.40 MB)
Study Region: We investigate the event runoff response in six sub-catchments in the Lake Tana sub-basin, headwater of the Blue Nile basin, northwest Ethiopia. Steep and mountainous terrains surround floodplains, imposing runoff and soil erosion in the upper catchments and flooding and sedimentation at floodplains. This study was conducted in the upland runoff source catchments.
Study Focus: The focus is to investigate catchment characteristics that control the event runoff response in upland catchments, and how recent land management practices may have contributed to improved hydrological conditions. Event rainfall and runoff data were obtained at five-minute time steps through automated divers and tipping bucket rain gauges and related to catchment characteristics.
New Hydrological Insights for the Region: Our results show that the catchment event quickflow response was controlled by different factors of both natural and anthropogenic nature of which forest and shrubs, bund density and soil organic matter content were found to be the most important to reduce event quickflow. On the contrary, increase in cropland area caused an increase in quickflow. Through least square fitting procedure of the Natural Resources Conservation Service Curve Number method (NRCS-CN), a site specific abstraction ratio ( ) value of 0.01, rather than the commonly used 0.2 or 0.05, was found to be most appropriate for the sub-humid highlands of Ethiopia.
(Location: IWMI HQ Call no: e-copy only Record No: H051702)
(0.72 MB)
This study was conducted to evaluate the performance of two small-scale irrigation (SSI) schemes in the subhumid Ethiopian highlands. Water application at the farm level and flow velocity along the main canal were monitored using a Parshall flume and current meter, respectively. The infiltration was measured at the head, middle and tail of the scheme within the command area using a double-ring infiltrometer. Soil samples were collected using an auger up to 60 cm in depth. Climatic and agronomic data were supplied to the crop water assessment tool (CROPWAT) to determine crop water requirements. The results showed that the average conveyance efficiency for the lined main canal was 90% and 92% for the Mugie and Fesas SSI schemes, respectively. The conveyance efficiency for the unlined main canal was in the order of 86% and 87% for the Mugie and Fesas SSI schemes, respectively. On the other hand, the average application efficiency and overall efficiency were found to be 56% and 51%, respectively, with a storage efficiency of 50% for the Mugie irrigation scheme. Similarly, the overall, application and storage efficiencies were 50%, 54% and 56%, respectively, for the Fesas irrigation scheme. Failure of operating gates, canal siltation and leakage through the main canals were the main causes of poor performance.
Powered by DB/Text
WebPublisher, from