Tillage effects on physical qualities of a vertisol in the central highlands of Ethiopia

In the highlands of Ethiopia, tillage methods and frequency affect drainage, soil erosion, moisture conservation, weeding and harvesting of crops. This is through their effects on soil physical, chemical and biological qualities. In this study, four tillage methods for land preparation, “broad bed and furrows”,” green manure”, “reduced tillage “and the traditional tillage “ridge and furrows” were evaluated for their effects on soil physical quality indicators. The study was superimposed on the field experiment conducted on a vertisol area at Caffee doonsa for five years (1998 to 2002) in the central highland of Ethiopia. Penetration resistance (PR), aggregate stability, water-holding capacity, crust strength and thickness, texture, porosity, saturated hydraulic conductivity, bulk density and water holding capacity were the soil physical quality indicators considered. The result indicated that only PR was significantly (p<0.05) affected, where as the other parameter have shown a slight changes that are consistent with the effects on the bio-chemical parameters as previously reported. Broad bed furrows, and reduced tillage resulted in the highest and the lowest PR, respectively under both the moist and dry soil conditions. Green manure  increased aggregate stability and reduced surface crust strength, which was linked to its increased organic matter content and consequent improved microbial activities.Keywords: Broad bed and furrow, green manure, reduced tillage, ridge and furrow, soil quality, land preparation

Land use land cover dynamics at Bilate Alaba sub-watershed, southern Ethiopia

This study was intended to detect land use/land cover changes over 44 years in the Bilate Alaba Subwatersed, Southern Ethiopia. Four Landsat images (1972, 1986, 2008 and 2017) were used to as inputs to produce four land cover maps of the subwatershed; ERDAS imagine and ArcGIS software were utilized to accomplish the analysis. In the period between 1972 to1986 cultivated and settlement showed an incremental change by 280.91 and 71.43 ha respectively, while bare land and shrub & grass land decreased by 225.26 and 140.25 ha respectively. In the period 1986 to 2008 cultivated and bare land increased by 105.13 and 52.90 ha while forest and shrub & grass land decreased by 103.41 and 50.84 ha respectively. Between 2008 and 2017 settlement and bare land increased by 83.20 and 65.54 ha respectively while shrub & grass land and forest land decreased by 112.59 and 46.16 ha respectively. The results showed that cultivated land and settlement land expanded by 67.38% and 532% respectively whereas forest land, shrub land &grass land declined by 66.35%, 18.36% respectively over the analysis period (1972-2017). There should be appropriate rural land use/management policy by identifying proper land for specific purpose so that degraded lands would not put under cultivation.Keywords: Land use, Land cover, GIS, Landsa

Water implications of foreign direct investment in Ethiopia's agricultural sector

Ethiopia is often highlighted as a country in which a lot of foreign land acquisition is occurring. The extent to which these investments also constitute significant acquisitions of water is the subject of this paper. It is apparent that water availability is a strong driver of the recent surge of investments in agricultural land globally, and in general the investments occur in countries with significant 'untapped' water resources. Ethiopia is no exception. We propose that the perception of unused and abundant water resources, as captured in dominant narratives, that drives and justifies both foreign and domestic investments, fails to reflect the more complex reality on the ground. Based on new collections of lease information and crop modelling, we estimate the potential additional water use associated with foreign investments at various scales. As a consequence of data limitations our analyses provide only crude estimates of consumptive water use and indicate a wide range of possible water consumption depending on exactly how foreign direct investment (FDI) development scenarios unfold. However, they do suggest that if all planned FDI schemes are implemented and expanded in the near future, additional water consumption is likely to be comparable with existing water use in non-FDI irrigation schemes, and a non-trivial proportion of the country's water resources will be effectively utilised by foreign entities. Hence, additional water use as well as local water scarcity ought to be strong considerations in regulating or pricing land leases. If new investments are to increase local food and water security without compromising local and downstream water availability they should be designed to improve often very low agricultural water productivity, and to safeguard access of local populations to water

Enhancing farming system water productivity through alternative land use and water management in vertisol areas of Ethiopian Blue Nile Basin (Abay)

Until recently, the Ethiopian government's investment did not systematically target high potential areas for agricultural intensification, limiting the potential productivity gains. Waterlogged vertisols, which cover about 2.7 million hectares in the Ethiopian part of the Blue Nile Basin, are among the high potential soils where management interventions could result in positive impacts. This study utilized soil, climate, crop and livestock productivity data and models to demonstrate intensification strategies which can increase crop-livestock system productivity. To understand the effects of alternative land use and water management interventions on water productivity, the areas have been classified into three drainage status depending on slope classes. Accordingly, non-drainable (0–2%), drainable (2–5%) and naturally drained (>5%) respectively, represented areas where artificial drainage is not feasible, where drainage using broad bed and furrows (BBF) is recommended, and areas where waterlogging is not a problem and no intervention is needed. Early planting of wheat (Triticum spp.) on BBF instead of the traditional late planting on flat beds in drainable areas and rice (Oryza sativa) cultivation instead of the traditional extensive grazing or growing grass-pea (Lathyrus sativus) on the flat areas provide viable alternative cropping options. Yield data of the crops and biomass of the native grass were obtained from research stations in the area while the effective rainfall and crop water requirement were estimated using CROPWAT Model. The value of the native grass and crop straw as livestock feed was estimated based on previous works. With respect to effective rainfall, the water productivity increase due to BBF over the control ranged from 5% to 200%, with an average increase of 57%. Despite higher water consumption of rice, feeding its residues to livestock enhanced the overall economic water productivity of the system as compared to the natural grazing or grass-pea cultivation. This can be accounted for by higher rice biomass productivity and the greater demand for its grain. The study demonstrated that draining the excess water when the slope allows, growing suitable high value crops on non-drainable areas, and integration of livestock into improved land and water management enhance overall agricultural system water productivity

ICRISAT Research Program on Markets, Institutions and Policies

The management of international agricultural research faces many challenges especially with regard to priority setting. Research managers have to provide clear direction in pursuing long-term strategic goals, and at the same time be responsive to change and demonstrate accomplishment of short-term objectives. They also need to address international development concerns and respond sensitively to wishes of a broad array of beneficiary and stakeholder groups..

Morphoecological characteristics of grasses used to restore degraded semi‐arid African rangelands

Peer reviewe

Reference soil groups map of Ethiopia based on legacy data and machine learning-technique: EthioSoilGrids 1.0

Up-to-date digital soil resource information and its comprehensive understanding are crucial to supporting crop production and sustainable agricultural development. Generating such information through conventional approaches consumes time and resources, and is difficult for developing countries. In Ethiopia, the soil resource map that was in use is qualitative, dated (since 1984), and small scaled (1 : 2 M), which limit its practical applicability. Yet, a large legacy soil profile dataset accumulated over time and the emerging machine-learning modeling approaches can help in generating a high-quality quantitative digital soil map that can provide better soil information. Thus, a group of researchers formed a Coalition of the Willing for soil and agronomy data-sharing and collated about 20 000 soil profile data and stored them in a central database. The data were cleaned and harmonized using the latest soil profile data template and 14 681 profile data were prepared for modeling. Random forest was used to develop a continuous quantitative digital map of 18 World Reference Base (WRB) soil groups at 250 m resolution by integrating environmental covariates representing major soil-forming factors. The map was validated by experts through a rigorous process involving senior soil specialists or pedologists checking the map based on purposely selected district-level geographic windows across Ethiopia. The map is expected to be of tremendous value for soil management and other land-based development planning, given its improved spatial resolution and quantitative digital representation.</p