Household energy and recycling of nutrients and carbon to the soil in integrated crop-livestock farming systems : a case study in Kumbursa village, Central Highlands of Ethiopia

Acknowledgements We are grateful to the farmers of Kumbursa village for their wholehearted cooperation in providing genuine responses to interview questions during the household survey. We are also thankful to the Development Agent of Kumbursa village, Mr Dinku Chala, for facilitating our relations with farmers of the study area and for participating in data collection. We are indebted to Addis Ababa University and AUC funded Afri-Flame project (Adaptation of small-scale biogas digesters for use in rural households in Sub-Saharan Africa) for their joint financial support. Our heartfelt gratitude also goes to the staff of Debre Zeit Agricultural Research Center for their cooperation in nutrient content analysis of crop residues and dung cakes. Finally, we owe our heartfelt indebtedness to the two anonymous reviewers for their constructive comments which greatly contributed to the improvement and final refinement of this paperPeer reviewedPublisher PD

Policies for improved land management and agricultural market development in the Ethiopian highlands

“The objectives of this workshop are to review and discuss the main findings and policy implications of recent research conducted on these topics by IFPRI, Wageningen University and Research Center (WUR), the International Livestock Research Institute (ILRI), Mekelle University (MU), the Ethiopian Agricultural Research Organization (EARO) and other Ethiopian collaborators; to discuss options for improving the development of agricultural markets and land management in Ethiopia, considering different stakeholders’ perspectives; and to develop recommendations for priority policy actions and further research based upon lessons learned from the research and remaining knowledge gaps. IFPRI has worked for more than a decade in Ethiopia studying the root causes of the interrelated problems of famine, rural poverty, low agricultural productivity and natural resource degradation, and helping to identify strategies and policies to overcome these problems. The need for effective and efficient markets for agricultural commodities and productive inputs, as well as effective measures to combat land degradation are clearly recognized by the government of Ethiopia in its current rural development strategy and poverty reduction strategy. Ethiopia has made great strides in recent years in increasing farmers’ access to productive technologies. Yet as we are all increasingly aware, these advances are necessary but not sufficient to achieve the goal of agriculturally led industrialization. Market development and sustainable natural resource management are essential building blocks of a successful rural development strategy, requiring policy makers and other stakeholders to identify and invest in an appropriate mix of institutions, infrastructure, information, and innovation systems. This workshop is intended to help contribute to these important efforts by taking stock of what is known and what we have learned from several years of recent research on sustainable land management and agricultural market development

Management of harvested C in smallholder mixed farming in Ethiopia

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What is the potential for biogas digesters to improve soil carbon sequestration in Sub-Saharan Africa? Comparison with other uses of organic residues

Acknowledgments We are very grateful to the UK Department for International Development (DFID) New and Emerging Technologies Research Call for funding this work. PS is a Royal Society-Wolfson Research Merit Award holder.Peer reviewedPostprin

Soil Nutrient Budgets and Flows in Smallholder Farming System of Ethiopia: Review

Primary nutrients like N, P and K are common for crop production in smallholder farms in Ethiopia. Nutrient budgets and flows in most farming systems play a crucial role in agricultural production and may lead to either depletion or accumulation of nutrients. This review showed trends of nutrient flows and balances in a farming systems as a result of different deriving forces, differences in farming systems, variability in soil fertility and management strategies. The review highlights the potential sources of nutrients and balance approaches as an indicator of soil nutrient mining in smallholder farming systems in the country. There is insufficient awareness on the levels of nutrient depletion in Ethiopia due to limited research conducted related nutrient mining and depletion even though there are different assessments made by different authors at small holder levels. Keywords: Soil nutrient budget, Soil fertility, nutrient replenishment, crop production DOI: 10.7176/JBAH/11-14-02 Publication date:July 31st 202

What is the potential for biogas digesters to improve soil fertility and crop production in Sub-Saharan Africa?

Acknowledgements We are very grateful to the UK Department for International Development (DFID) New and Emerging Technologies Research Call for funding this work. PS is a Royal Society-Wolfson Research Merit Award holder.Peer reviewedPostprin

Feed resources availability, utilization and marketing in central and eastern Tigray, northern Ethiopia

This survey explored the situation of different feed resources for ruminant livestock in two zones (central and eastern) in Tigray region of northern Ethiopia. These two zones account for the region’s 12% of the total land mass, 23% of the human population, 28% of the cattle population, and 56% of the small ruminant population. Farmers feed their livestock a variety of feed resources that range from crop residues to non-conventional feeds.The overall contribution of crop residues exceeds 50% of the livestock feeds currently used by smallholder farmers, and this reflects the level of integration between crop and livestock farming. Overall, the management and utilization of crop residues with particular attention to collection and transportation is constrained by factors such as labour shortage, distance from harvesting field to animals and delayed harvest in the project districts. Grazing land management and improvement is seldom considered by farmers or the extension system. Acute shortages of AIBPs supply from the sources and high price fluctuation in the main towns of the districts are discouraging smallholder dairy and small ruminant farmers from using them on a regular basis. The contribution of improved forage plants is not as expected and forage genetic material multiplication sites are operating with insufficient budget and manpower, and not supported by proper research. The overall feed supply to demand ratio in four districts in the eastern zone is not enough to cover the annual maintenance requirements of the present stock

Influence of farmers’ socio-economic characteristics on nutrient flow and implications for system sustainability in smallholdings: a review

This research article was published by Frontiers in Soil Science in 2023The rise in global human population, coupled with the effects of climate change, has increased the demand for arable land. Soil fertility has been the most affected, among other things. Many approaches to soil fertility management have been proposed by studies in Sub-Saharan Africa (SSA); however, the question of sustainability remains. Nutrient monitoring (NUTMON), which combines biophysical and socio-economic features for soil fertility management, gives an in-situ soil fertility status of a given land use system, which ultimately provides guidance in proposing appropriate soil management techniques in a given land use system. In this review, the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) approach was deployed for a systematic search of the literature materials. The review evaluated various studies on nutrient monitoring in SSA soils in order to understand the socioeconomic attributes and their influence on farming systems, as well as nutrient flow and balances. The review identified two dominant smallholder farming systems in SSA: mixed crop-livestock and mixed crop farming systems. Also, this review revealed that most nutrient balance studies in SSA have been done in mixed crop and livestock farming systems. However, regardless of the farming systems, the overall mean nutrient balances in all studies, particularly those of nitrogen (N) and potassium (K), were negative, indicating significant nutrient mining. The review further revealed a vast range of biophysical soil fertility management technologies; however, their adoption has been limited by socio-economic aspects including land ownership, gender, financial position, literacy level, and access to inputs. Therefore, in view of this situation, integrating biophysical and socioeconomic disciplines could address the problem of soil nutrient depletion holistically, thus decreasing the existing negative nutrient balances in the SSA region

Effects of combined application of phosphorus and sulfur fertilizers on agronomic traits and protein content of supplementary irrigated haricot bean (Phaseolus vulgaris) varieties in Raya Valley, Northern Ethiopia

Haricot bean is primarily grown in Ethiopia for human consumption and export earnings. A market demand for haricot bean, both in the domestic and export market, has triggered the production of haricot bean in selected areas of Ethiopia though its production is constrained by several factors such as poor soil fertility and erratic rainfall. This study was carried out to investigate the combined effect of phosphorus and sulfur fertilizers on yield, yield related traits and protein content of haricot bean (Phaseolus vulgaris) varieties at the research field of Mekoni Agricultural Research Center during 2016/17 cropping season. The experiment was laid out in split plot design where varieties were assigned to the main plots and fertilizer rates to the sub plots in three replications. Three phosphorus (P) rates (10, 20 and 30 kg ha-1) were combined with four sulfur (S) rates (15, 30, 45 and 60 kg ha-1) and applied in combination to Melka Awash-98 and Nasir varieties. Data on phenological, agronomic and quality traits were collected and determined. Partial budget analysis was carried out to assess the profitability of the applications. P-S fertilizer treatments were  significantly affected by varieties. Treatments were significantly affected by varieties and the imposed P and S rates. The interaction effect due to variety by fertilizer the two factors significantly affect days to flowering, plant height, hundred seed weight and protein content. Tallest plants, fewer days to flowering and maturity, many pods/plant, heavier seeds, higher grain yield ha-1 and better protein content were recorded where the fertilizer application rate was 20 kg ha-1P and 30 kg ha-1 S for both varieties. Grain yield ranged from 1520 to 3000 kg ha-1 depending on P-S fertilizer rates and varieties. Nasir variety seems to be superior over Melka Awash-98 for most traits except protein content. However, production of Melka Awash-98 under 20 kg ha-1P and 15 kg ha-1 S fertilization tend to be more economical as it resulted in highest net benefit return. Although not profitable, planting Melka Awash-98 using an application rate of 20 kg ha-1P and 30 kg ha-1 S could be suggested for use in the area to ensure earliness and high grain yield