Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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Tradeoffs around crop residue biomass in smallholder crop-livestock systems - What's next?
Tittonell, P.A. ; Gérard, B. ; Erenstein, O. - \ 2015
Agricultural Systems 134 (2015). - ISSN 0308-521X - p. 119 - 128.
sub-saharan africa - define conservation agriculture - soil fertility management - south-western niger - food-feed crops - ecological intensification - farming systems - impact assessment - appropriate use - 4th principle
Much has been written on the tradeoffs that smallholder farmers face when having to allocate their biomass resources among competing objectives such as feed, fuel, mulch, compost or the market. This paper summarises yet a new body of evidence from 10 studies on tradeoffs in the allocation of cereal crop residue biomass between soil management and livestock feeding in developing regions, published in the special issue of Agricultural Systems ‘Biomass use tradeoffs in cereal cropping systems: Lessons and implications from the developing world’. The studies cover a diversity of socio-ecological contexts, farming system types and scales of analysis. We reflect on their main findings and methodological progress, and on the new and not-so-new implications of these findings for research and action in the development agenda. We propose stylised graphical models to portray tradeoffs and plausible trajectories towards synergies, in the hope that such generalisations would prevent further efforts to ‘reinvent the wheel’ in the realm of tradeoffs analysis. We advocate an ex-post impact assessment of recent investments in systems research to help focus such research further and clearly define its future role in prioritizing and targeting development interventions.
Land-based adaptation to global change: what drives soil and water conservation in Western Africa?
Sietz, D. ; Dijk, H. van - \ 2015
Global environmental change : human and policy dimensions 33 (2015). - ISSN 0959-3780 - p. 131 - 141.
factors influencing adoption - sub-saharan africa - burkina-faso - agricultural innovations - farmers perceptions - dryland development - northeast brazil - central plateau - southern mali - cover change
Conservation of land resources is a promising strategy for sustainable agricultural intensification in order to adapt dryland farming systems to climate, market and other stresses. At a local level, factors that drive the adoption of conservation measures operate and interact in specific ways. Linking our knowledge of the local specifications of these drivers to regional and global patterns of vulnerability can significantly enhance our understanding of land-based adaptation to global change. However, the factors that influence the adoption of conservation practices remain actively debated. Therefore, this study presents a meta-analysis of case studies that investigate the adoption of soil and water conservation measures, as an important approach to resource conservation. Synthesising 63 adoption cases in the drylands of western Africa, this meta-analysis reveals a multitude of factors that drive the adoption of soil and water conservation practices. The drivers differ strongly between particular practices and methods of analysis used in the case studies. Contributing to the broader debate on resource conservation, the findings highlight the adoption of soil and water conservation measures as an emergent property of farming systems. They demonstrate the need to better understand the socio-ecological foundation of adoption and the pathways along which adoption evolves in space and time. This study concludes with methodological principles to advance future research on the factors that drive the adoption of soil and water conservation measures as a pre-requisite of improving land-based adaptation efforts.
Strategies for improving water use efficiency in livestock feed production in rain-fed systems
Kebebe, E.G. ; Oosting, S.J. ; Haileslassie, A. ; Duncan, A.J. ; Boer, I.J.M. de - \ 2015
Animal 9 (2015)05. - ISSN 1751-7311 - p. 908 - 916.
sub-saharan africa - life-cycle assessment - agriculture - management - ethiopia - adoption - intensification - farmers - trials - straw
Livestock production is a major consumer of fresh water, and the influence of livestock production on global fresh water resources is increasing because of the growing demand for livestock products. Increasing water use efficiency of livestock production, therefore, can contribute to the overall water use efficiency of agriculture. Previous studies have reported significant variation in livestock water productivity (LWP) within and among farming systems. Underlying causes of this variation in LWP require further investigation. The objective of this paper was to identify the factors that explain the variation in LWP within and among farming systems in Ethiopia. We quantified LWP for various farms in mixed-crop livestock systems and explored the effect of household demographic characteristics and farm assets on LWP using ANOVA and multilevel mixed-effect linear regression. We focused on water used to cultivate feeds on privately owned agricultural lands. There was a difference in LWP among farming systems and wealth categories. Better-off households followed by medium households had the highest LWP, whereas poor households had the lowest LWP. The variation in LWP among wealth categories could be explained by the differences in the ownership of livestock and availability of family labor. Regression results showed that the age of the household head, the size of the livestock holding and availability of family labor affected LWP positively. The results suggest that water use efficiency could be improved by alleviating resource constraints such as access to farm labor and livestock assets, oxen in particular.
Participatory appraisal of institutional and political constraints and opportunities for innovation to address parasitic weeds in rice
Schut, M. ; Rodenburg, J. ; Klerkx, L.W.A. ; Hinnou, L.C. ; Kayeke, J. ; Bastiaans, L. - \ 2015
Crop Protection 74 (2015). - ISSN 0261-2194 - p. 158 - 170.
fed lowland rice - striga-hermonthica control - raais rapid appraisal - sub-saharan africa - socioeconomic constraints - integrated analysis - pest-management - systems - benin - tanzania
Parasitic weeds in smallholder rice production systems, of which Striga asiatica, Striga hermonthica and hamphicarpa fistulosa are the main representatives, form an increasing problem for food and income security in sub-Saharan Africa (SSA). The objective of this paper is to identify institutional and political constraints and opportunities for innovation to address parasitic weed problems in rice. Constraints and opportunities for innovation were studied across three nested systems: the parasitic weed control system, the crop protection system, and the agricultural system. Multi-stakeholder workshops, interviews and surveys were held to gather data on key constraints faced by different stakeholder groups across three parasitic weed infested study sites in both Tanzania and Benin. The results demonstrate that in both countries, the majority of institutional and political constraints relate to the functioning of the broader crop protection and agricultural systems and not specifically to parasitic weeds. Although differences were observed between the two countries and the different stakeholder groups, the majority of constraints perceived by the stakeholders were caused by a lack of capabilities and resources and a limited access to credit. Awareness raising of parasitic weed problems among farmers, extension and crop protection officers at the local level, combined with improved input and service supply and enhanced agricultural education and training curricula at the national level, were identified as important elements for improvement. More structural collaboration between key stakeholder groups is expected to contribute to a better recognition of agricultural problems, like that of parasitic weeds in rice, and a more timely identification of feasible solutions.
Effects of technical interventions on flexibility of farming systems in Burkina Faso: Lessons for the design of innovations in West Africa
Andrieu, N. ; Descheemaeker, K.K.E. ; Sanou, T. ; Chia, E. - \ 2015
Agricultural Systems 136 (2015). - ISSN 0308-521X - p. 125 - 137.
crop-livestock systems - sub-saharan africa - climate-change - smallholder farmers - coping strategies - modeling approach - decision-making - constraints - uncertainty - variability
African farmers have always been exposed to climatic and economic variability and have developed a range of coping strategies. Such strategies form part of flexible farm management, an ability that may prove very valuable in the face of future climate change and market dynamics. The generally low productivity of African smallholder farming systems is usually addressed by research and development institutions by a variety of solutions for improving farm performance. However, changes to the system may affect the flexibility of farms and thus their ability to cope with variability. We quantified the added value of being flexible and how this flexibility is affected by technical changes, such as composting and cattle fattening recurrently proposed and promoted by research and development institutions and projects. The study was conducted in two villages of the agro-pastoral area of Burkina Faso, where livestock, cereals and cotton are the main farming activities. A whole-farm simulation model was developed based on information gathered during focus group meetings with farmers and detailed individual monitoring of farmers' practices. The model simulates farmers' decision rules governing the management of the cropping and livestock farm components, as well as crop and livestock production and farm gross margin. Using the existing decision rules, current farm performance was simulated by assessing the cereal balance, the fodder balance and the whole farm gross margin. Then, by comparing the mean and the coefficient of variation of these indicators resulting from (a) the existing decision rules (baseline scenario) and (b) a set of less flexible rules (rigid scenario), the added value of flexible management was revealed. The adoption of composting practices allowed a slight increase in gross margin associated with a decrease in its between-year variability in comparison with conventional practices. Cattle fattening only led to a higher gross margin in the years with high rainfall and low input prices when no management practices were used to limit dependence on external input. This kind of technical change thus requires increased management agility by farmers to deal with climatic and economic variability. We conclude that assessing the impact of technical interventions not only in terms of productivity but also in terms of changes in flexibility is useful for a better understanding of potential adoption of technical changes
From farm scale synergies to village scale trade-offs: Cereal crop residues use in an agro-pastoral system of the Sudanian zone of Burkina Faso
Andrieu, N. ; Vayssières, J. ; Corbeels, M. ; Blanchard, M. ; Vall, E. ; Tittonell, P.A. - \ 2015
Agricultural Systems 134 (2015). - ISSN 0308-521X - p. 84 - 96.
west-african savanna - sub-saharan africa - livestock systems - conservation agriculture - fertility management - phosphorus budget - soil fertility - spatial carbon - nitrogen - flows
Traditionally, cereal crop harvest residues are communally grazed by the ruminant herds of villagers and transhumant pastoralists in the agro-pastoral systems which predominate in the savannah zone of West Africa. We analysed the impact of the private use of crop residues by individual farmers on crop and livestock productivity at three scales: the field, farm, and village. We collected data in the village of Koumbia, located in the Sudanian region of Burkina Faso. Three types of farmers were identified: resource-poor farmers, predominantly livestock farmers, and resource-rich farmers. The trade-offs between different uses and users of cereal crop residues at the three scales were analysed through field surveys and a simple model of biomass flows. We considered current communal use practices and two alternative scenarios of private cereal crop residue use: (i) for composting (fertility scenario) and (ii) as fodder (fodder scenario). Our analysis of current practices confirmed that farmers left around 80% of cereal crop residues on their fields. Soil fertility for cereal production therefore could be improved through crop residue management at the farm scale. We also found that communal grazing benefited farmers with high numbers of livestock. Maize grain production at the farm scale was improved in both of the simulated scenarios. Yet these scenarios had a negative impact on fodder self-sufficiency at the village scale, and on the N balance of the savannah-derived rangelands. The negative impact was greater in the fertility scenario than the fodder stock scenario. Increasing cereal productivity at the farm scale cannot be achieved without considering the trade-offs involved at the village scale. Changes in practices will require negotiations between the different types of farmers involved. Participatory innovation platforms with discussion support tools like the model presented in our study can facilitate such negotiations.
Rhamphicarpa fistulosa, a widespread facultative hemi-parasitic weed, threatening rice production in Africa
Rodenburg, J. ; Morawetz, J.J. ; Bastiaans, L. - \ 2015
Weed Research 55 (2015). - ISSN 0043-1737 - p. 118 - 131.
sub-saharan africa - fed lowland rice - phylogenetic-relationships - rhinanthus-minor - scrophulariaceae - vegetation - orobanchaceae - management - haustoria - habitats
Rhamphicarpa fistulosa is a facultative hemi-parasitic plant of the Orobanchaceae family, adapted to wet soils. Apart from tropical Australia, it is only found in sub-Saharan Africa, where it is considered a minor weed in cereal crops such as rice. Due to this status, the species has received only sporadic attention. Recent field observations and encounters with rice farmers in several African countries showed that R. fistulosa is, however, a more serious and increasing production constraint than previously thought. Results from a systematic literature review and a global herbarium study support this. The species has a broad distribution over Africa (at least 35 countries from Madagascar to Senegal and from Sudan to South Africa) and a wide range in altitude (0–2150 m a.s.l.) and environment (waterlogged swamps to moist free-draining uplands). Rhamphicarpa fistulosa is relatively independent and persistent because of the presumably wide host range, the facultative nature of its parasitism and its prolific seed (estimated 100 000 seeds m-2 under moderate infestation levels). Finally, R. fistulosa causes severe yield losses (average 60%) and high regional annual economic losses (estimated US $175 million), while effective control options are scant and awareness of the species among important R&D stakeholders is almost absent. An integrated approach is advocated to assist the rice sector to reduce current R. fistulosa-inflicted losses and to prevent further spread of the species into new areas.
Institutions and access to woodfuel commerce in the Democratic Republic of Congo
Schure, J.M. ; Ingram, V. ; Arts, B.J.M. ; Levang, P. ; Mvula-Mampasi, E. - \ 2015
Forest Policy and Economics 50 (2015). - ISSN 1389-9341 - p. 53 - 61.
sub-saharan africa - developing-countries - poverty alleviation - rural livelihoods - value chains - charcoal - forests - policy - conservation - perspectives
A new generation of woodfuel studies focuses on the political dynamics behind access to the woodfuel trade, providing better insights into patterns of inclusion and exclusion and options for resource management. Institutional mechanisms that govern access are difficult to untangle in the context of informal trade. This paper analyzes institutions and how they regulate access to commercialize woodfuel in two areas in the Democratic Republic of Congo (DRC). A review of empirical data (surveys and interviews) and secondary data on wood energy value chains in the DRC is used to examine the ways that woodfuel institutions affect access to resources and to markets. The main findings are that existing formal mechanisms regulating access to the woodfuel trade are hardly enforced. Informal, socially embedded institutions generally govern access, and the trade is open to less privileged and rural actors. People who benefit from these informal arrangements have many vested interests, and current production patterns are unsustainable and not sufficiently mitigated by these institutions. New strategies are required that promote the positive aspects of informality, while supporting initiatives that contribute to long-term resource sustainability and meet the high levels of urban demand, given the lack of alternative energy sources.
RAAIS: Rapid Appraisal of Agricultural Innovation Systems (Part I). A diagnostic tool for integrated analysis of complex problems and innovation capacity
Schut, M. ; Klerkx, L.W.A. ; Rodenburg, J. ; Kayeke, J. ; Hinnou, L.C. ; Raboanarielina, C.M. ; Adegbola, P.Y. ; Ast, A. van; Bastiaans, L. - \ 2015
Agricultural Systems 132 (2015). - ISSN 0308-521X - p. 1 - 11.
sub-saharan africa - fed lowland rice - framework - policy - perspective - benin - participation - information - reflection - management
This paper introduces Rapid Appraisal of Agricultural Innovation Systems (RAAIS). RAAIS is a diagnostic tool that can guide the analysis of complex agricultural problems and innovation capacity of the agricultural system in which the complex agricultural problem is embedded. RAAIS focuses on the integrated analysis of different dimensions of problems (e.g. biophysical, technological, socio-cultural, economic, institutional and political), interactions across different levels (e.g. national, regional, local), and the constraints and interests of different stakeholder groups (farmers, government, researchers, etc.). Innovation capacity in the agricultural system is studied by analysing (1) constraints within the institutional, sectoral and technological subsystems of the agricultural system, and (2) the existence and performance of the agricultural innovation support system. RAAIS combines multiple qualitative and quantitative methods, and insider (stakeholders) and outsider (researchers) analyses which allow for critical triangulation and validation of the gathered data. Such an analysis can provide specific entry points for innovations to address the complex agricultural problem under study, and generic entry points for innovation related to strengthening the innovation capacity of agricultural system and the functioning of the agricultural innovation support system. The application of RAAIS to analyse parasitic weed problems in the rice sector, conducted in Tanzania and Benin, demonstrates the potential of the diagnostic tool and provides recommendations for its further development and use.
RAAIS: Rapid Appraisal of Agricultural Innovation Systems (Part II). Integrated analysis of parasitic weed problems in rice in Tanzania
Schut, M. ; Rodenburg, J. ; Klerkx, L.W.A. ; Kayeke, J. ; Ast, A. van; Bastiaans, L. - \ 2015
Agricultural Systems 132 (2015). - ISSN 0308-521X - p. 12 - 24.
sub-saharan africa - fed lowland rice - west-africa - management - framework - policy - determinants - networks - science - design
Parasitic weeds such as Striga spp and Rhamphicarpa fistulosa in smallholder rice production systems form an increasing problem for food and income security in sub-Saharan Africa. In this paper we implement the Rapid Appraisal of Agricultural Innovation Systems (RAAIS) as a diagnostic tool to identify specific and generic entry points for innovations to address parasitic weeds in rain-fed rice production in Tanzania. Data were gathered across three study sites in Tanzania where parasitic weeds are eminent (Kyela, Songea Rural and Morogoro Rural districts). The results demonstrate that in Tanzania, weeds in general and parasitic weeds in particular receive little attention in agricultural research, training and education curricula. Crop protection policies mainly focus on the control of (insect) pest and diseases and there is relatively little attention for weed prevention, which is essential for addressing parasitic weed problems effectively. Specific entry points for innovation include increasing awareness of parasitic weed problems among farmers, extension and crop protection officers and policymakers. In regions where awareness is relatively high, participatory research approaches can provide a basis for developing locally adapted parasitic weed management strategies. Generic entry points for innovation include enhanced collaboration and interaction between stakeholders across different levels, for example in multi-stakeholder platforms. This can provide the basis for developing and implementing coherent policy and development strategies to address structural constraints in the agricultural system, including the promotion of clean local seed systems, investments in physical and knowledge infrastructure development, adequate backstopping of agricultural extension officers, agribusiness training for farmers, quality control of agricultural inputs, timely access to agricultural inputs, and improved access to markets for farmers. Together the specific and generic entry points can strengthen the innovation capacity of Tanzania's agricultural system to address parasitic weed problems, as well as other complex agricultural problems.
Land tenure in China: Legal, actual and perceived security
Ma, Xianlei ; Heerink, N. ; Feng, S. ; Shi, X. - \ 2015
Land Use Policy 42 (2015). - ISSN 0264-8377 - p. 293 - 306.
agricultural productivity growth - land rental markets - sub-saharan africa - property-rights - investment incentives - technical efficiency - economic-development - housing improvement - social-security - buenos-aires
This paper examines the magnitudes of legal security, actual security and perceived security of farmland tenure, and the causes of currently prevailing land tenure insecurity in rural China. Two farm household surveys conducted in the northwest of Gansu province in 2010 and in the northeast of Jiangxi province in 2011 are used as case studies. Although recent land tenure reforms have significantly improved legal tenure security, we find that farm households still experience substantial insecurity of actual and perceived land tenure. We argue that social security considerations, ambiguous formulations of laws, and village self-governance rules are three important underlying causes. Actual and perceived land tenure security is lowest in the case study region in Jiangxi province even though the share of off-farm income in rural household incomes is much larger in that region. We explain this finding from investments in land quality improvement made by rural households in the Gansu case study region, the larger per capita land resources in that region, and the limited social security provided by off-farm employment.
Farm diversity, resource use efficiency and sustainable land management in the western highlands of Kenya
Mutoko, M.C. ; Hein, L.G. ; Shisanya, C.A. - \ 2014
Journal of Rural Studies 36 (2014). - ISSN 0743-0167 - p. 108 - 120.
soil fertility management - sub-saharan africa - technical efficiency - rural poverty - degradation - conservation - agriculture - impact - growth - maize
Sub-Saharan Africa (SSA) faces further population growth in the coming decades and it is essential to increase food production in rural areas. However, development programs to enhance agricultural productivity have achieved mixed results. This study investigates farm household responses to a changing agro-environment in one of the most densely populated rural districts in SSA and examines practical implications for the promotion of sustainable land management (SLM) practices. The specific objective is to analyze farm diversity and resource use efficiency and their implications for promoting SLM in the highlands of Western Kenya. We carried out an elaborate survey of 236 households, and applied multivariate analysis to analyze farm efficiency and livelihood strategies. We found major differences in responses to a changing agro-environment between five farm types in terms of resource endowment, income strategies and farm practices. Across farm types, efficiency was low indicating poor land productivity. Our study shows that there has been a lack of intensification in land use and that households are increasingly depending on off-farm income. Our findings have a number of implications to programs aiming to promote sustainable land management in SSA. We propose that successful implementation of such programs requires targeting areas highly reliant on agriculture and within these areas focus on households mostly dependent on farming to sustain their welfare. (C) 2014 Elsevier Ltd. All rights reserved.
Identifying the potential for irrigation development in Mozambique: Capitalizing on the drivers behind farmer-led irrigation expansion
Beekman, P.W. ; Veldwisch, G.J.A. ; Bolding, J.A. - \ 2014
Physics and Chemistry of the Earth 76-78 (2014). - ISSN 1474-7065 - p. 54 - 63.
small private irrigation - sub-saharan africa - smallholder irrigation
Smallholder irrigation in Central Mozambique predominantly takes place in an informal setting. This renders these smallholders and their activities invisible for policy purposes. Identification efforts of smallholder irrigation as well as the potential for new irrigation development are often the basis for policy setting. But the potential is often approached technocratically: the technical availability of water and land with the assumption that smallholder irrigation is not happening and should be developed. Although more and more effort is done to include social economical aspects into the identification as well, it remains a GIS exercise, based on incomplete data using large pixel sizes, analyzing countries or continents as a whole. This study describes and presents the methodology and the results of an irrigation potential identification exercise carried out in two studies in Central Mozambique. Apart from describing the identification methods used, this study highlights the extent of farmer-led irrigation development, its drivers and the potential for farmer-led smallholder irrigation development. This study demonstrates the prolific nature of smallholder irrigation, arguing for the recognition that smallholder farmers are already developing irrigation and that this should lead to changing the focus of identification efforts towards the drivers behind farmer-led irrigation development. Using these context-specific drivers to define the potential for new irrigation development should result in a better response in policy to both the technical and socio-economical potential of smallholder irrigation development.
Agroforestry solutions to address climate change and food security challenges in Africa
Mbow, C. ; Neufeldt, H. ; Noordwijk, M. van; Minang, P.A. ; Kowero, G. ; Luedeling, E. - \ 2014
Current Opinion in Environmental Sustainability 6 (2014). - ISSN 1877-3435 - p. 61 - 67.
sub-saharan africa - forest degradation - land degradation - climate-change - west-africa - agriculture - systems - intensification - classification - security
Trees inside and outside forests contribute to food security in Africa in the face of climate variability and change. They also provide environmental and social benefits as part of farming livelihoods. Varied ecological and socio-economic conditions have given rise to specific forms of agroforestry in different parts of Africa. Policies that institutionally segregate forest from agriculture miss opportunities for synergy at landscape scale. More explicit inclusion of agroforestry and the integration of agriculture and forestry agendas in global initiatives on climate change adaptation and mitigation can increase their effectiveness. We identify research gaps and overarching research questions for the contributions in this special issue that may help shape current opinion in environmental sustainability.
Africa and the Green Revolution : A Global Historical Perspective
Frankema, E.H.P. - \ 2014
NJAS Wageningen Journal of Life Sciences 70-71 (2014). - ISSN 1573-5214 - p. 17 - 24.
sub-saharan africa - british africa - agriculture - revenue - origins - growth
Two decades of substantial economic growth in Africa have challenged the deep-seated Afro-pessimism of the 1990s and 2000s and re-invigorated the academic debate on Africa's ability to grow out of poverty in the 21st century. Although the opinions differ widely on how sustainable current African growth trajectories are, there is a widespread consensus that a fundamental agricultural transformation is key to consolidate current and future welfare gains. This study interprets recent signs of agricultural productivity growth from a long term global historical context, arguing that the combination of present-day developments in information and communication technology, transport infrastructure, demographic growth, urbanization and in macro-economic governance form a fundamental break with African history. This break does not offer any guarantees, but it does raise the probability that Africa will complete a green revolution of its own.
Metropolitan Blueprints of Colonial Taxation? Lessons from Fiscal Capacity Building in British and French Africa, c. 1880-1940
Frankema, E.H.P. ; Waijenburg, M.F.M. van - \ 2014
Journal of African History 55 (2014)3. - ISSN 0021-8537 - p. 371 - 400.
sub-saharan africa - growth - education - colonization - institutions - government - legacies - origins - history - world
The historical and social science literature is divided about the importance of metropolitan blueprints of colonial rule for the development of colonial states. We exploit historical records of colonial state finances to explore the importance of metropolitan identity on the comparative development of fiscal institutions in British and French Africa. Taxes constituted the financial backbone of the colonial state and were vital to the state building efforts of colonial governments. A quantitative comparative perspective shows that pragmatic responses to varying local conditions can easily be mistaken for specific metropolitan blueprints of colonial governance and that under comparable local circumstances the French and British operated in remarkably similar ways.
Determinants of parasitic weed infestation in rainfed lowland rice in Benin
N'cho, A.S. ; Mourits, M.C.M. ; Rodenburg, J. ; Demont, M. ; Oude Lansink, A.G.J.M. - \ 2014
Agricultural Systems 130 (2014). - ISSN 0308-521X - p. 105 - 115.
sub-saharan africa - rhamphicarpa-fistulosa - striga-hermonthica - farming systems - management - selection - scrophulariaceae - specification - demand - model
The parasitic weed Rhamphicarpa fistulosa is threatening rainfed lowland rice production in Benin. The aim of this study was to explore factors (such as biophysical characters of the rice growing environment, farmers’ management practices, and socioeconomic characteristics) that affect the infestation of rainfed lowland rice fields by R. fistulosa and farmers’ ability to cope with the problem. Data were collected from 231 rice plots located in 12 inland valleys infested by Rhamphicarpa in Benin. Data were analyzed using a double hurdle model, which analyses both the likelihood (of occurrence) and the severity of infestation. Results showed that 72% of the surveyed rice plots were infested by R. fistulosa and the average severity was 109 plants m-2. The likelihood of infestation was higher on poorly fertile soils and fields located in the inland-valley bottom, and it decreases through timely use of herbicides and ploughing. Severity of infestation was higher on rice plots cultivated by female-headed households farmers and reduced through management practices such as late sowing, timely application of post-emergence herbicide, three hoe or hand weeding operations, medium-rate fertilizer application and prolonged fallow. Likelihood and severity of infestation were found to be negatively correlated. These findings suggest that farmers can reduce the likelihood and the severity of infestation of their plot as long as they are aware of factors causing the problem given their access to and management capacity of production resources.
Implementation of The World Starts With Me, a comprehensive rights-based sex education programme in Uganda
Rijsdijk, L.E. ; Bos, A.E.R. ; Lie, R. ; Leerlooijer, J.N. ; Eiling, E. ; Atema, V. ; Gebhardt, W.A. ; Ruiter, R.A.C. - \ 2014
Health Education Research 29 (2014)2. - ISSN 0268-1153 - p. 340 - 353.
south-african schools - sub-saharan africa - secondary-schools - aids education - health-promotion - hiv prevention - hiv/aids - interventions - outcomes - fidelity
This article presents a process evaluation of the implementation of the sex education programme the World Starts With Me (WSWM) for secondary school students in Uganda. The purpose of this mixed-methods study was to examine factors associated with dose delivered (number of lessons implemented) and fidelity of implementation (implementation according to the manual), as well as to identify the main barriers and facilitators of implementation. Teachers’ confidence in teaching WSWM was negatively associated with dose delivered. Confidence in educating and discussing sexuality issues in class was positively associated with fidelity of implementation, whereas the importance teachers attached to open sex education showed a negative association with fidelity. Main barriers for implementing WSWM were lack of time, unavailability of computers, lack of student manuals and lack of financial support and rewards. Other barriers for successful implementation were related to high turnover of staff and insufficient training and guidance of teachers. Teachers’ beliefs/attitudes towards sexuality of adolescents, condom use and sex education were found to be important socio-cognitive factors intervening with full fidelity of implementation. These findings can be used to improve the intervention implementation and to better plan for large-scale dissemination of school-based sex education programmes in sub-Saharan Africa.
Functions and limitations of farmer cooperatives as innovation intermediaries: Findings from China
Yang, H. ; Klerkx, L.W.A. ; Leeuwis, C. - \ 2014
Agricultural Systems 127 (2014). - ISSN 0308-521X - p. 115 - 125.
international agricultural-research - sub-saharan africa - technological-change - systems perspective - networks - management - extension - knowledge - support
This article takes an innovation intermediary perspective to examine farmer cooperative’s (FC) roles in facilitating agricultural innovation and its positioning in the agricultural innovation system (AIS). The article draws experiences from the rapidly emerging FC field in China. Three cases are selected to cross check findings from them and innovation journey analysis is used within each case to understand FCs’ engagement in innovation processes. The findings show that FCs cover a wide range of knowledge intermediation and innovation intermediation functions identified by the literature. FCs recognize the importance to connect technical, social and economic dimensions of farming practice and provide corresponding services to link farmers to relevant actors, like extension agencies, research institutes and supermarkets. Though they mainly work through bilateral relationships as opposed to acting as a systemic intermediary, they could take the role of coordinator in the service system and bridge the gap between the research and policy system and everyday farming practice, especially in the absence of a systemic coordinator. However, their legitimacy as intermediary might be challenged due to the potential conflicts with governments, market actors or their members, and their local position may provide insufficient clout for developing durable relationships with relevant actors.
Climate-induced yield variability and yield gaps of maize (Zea mays L.) in the Central Rift Valley of Ethiopia
Kassie, B.T. ; Ittersum, M.K. van; Hengsdijk, H. ; Asseng, S. ; Wolf, J. ; Rotter, R.P. - \ 2014
Field Crops Research 160 (2014). - ISSN 0378-4290 - p. 41 - 53.
sub-saharan africa - use systems-analysis - crop growth-models - ecological intensification - fertilizer application - simulation-model - water-uptake - agriculture - adaptation - ceres
There is a high demand for quantitative information on impacts of climate on crop yields, yield gaps and their variability in Ethiopia, yet, quantitative studies that include an indication of uncertainties in the estimates are rare. A multi-model crop growth simulation approach using the two crop models, i.e. Decision Support System for Agro-Technology (DSSAT) and WOrld FOod STudies (WOFOST) was applied to characterize climate-induced variability and yield gaps of maize. The models were calibrated and evaluated with experimental data from the Central Rift Valley (CRV) in Ethiopia. Subsequently, a simulation experiment was carried out with an early maturing (Melkassa1) and a late maturing (BH540) cultivar using historical weather data (1984-2009) of three locations in the CRV. Yield gaps were computed as differences among simulated water-limited yield, on-farm trial yields and average actual farmers' yields. The simulation experiment revealed that the potential yield (average across three sites and 1984-2009) is 8.2-9.2 and 6.8-7.1 Mg/ha for the late maturing and early maturing cultivars, respectively; ranges indicate mean differences between the two models. The simulated water-limited yield (averaged across three sites and 1984-2009) is 7.2-7.9 Mg/ha for the late maturing and 6.1-6.7 Mg/ha for the early maturing cultivar. The water-limited yield shows high inter-annual variability (CV 36%) and about 60% of this variability in yield is explained by the variation in growing season rainfall. The gap between average farmers yield and simulated water-limited yield ranges from 4.7 to 6.0 Mg/ha. The average farmers' yields were 2.0-2.3 Mg/ha, which is about 1.1-3.1 Mg/ha lower than on-farm trial yields. In relative terms, average farmers' yields are 28-30% of the water-limited yield and 44-65% of on-farm trial yields. Analysis of yield gaps for different number of years to drive average yields indicates that yield gap estimation on the basis of few years may result in misleading conclusions. Approximately ten years of data are required to be able to estimate yield gaps for the Central Rift Valley in a robust manner. Existing yield gaps indicate that there is scope for significantly increasing maize yield in the CRV and other, similar agro-ecological zones in Africa, through improved crop and climate risk management strategies. As crop models differ in detail of describing the complex, dynamic processes of crop growth, water use and soil water balances, the multi-model approach provides information on the uncertainty in simulating crop-climate interactions. (C) 2014 Elsevier B.V. All rights reserved.
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