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Rufino M.C.,Wageningen University | Dury J.,Wageningen University | Tittonell P.,Wageningen University | Tittonell P.,CIRAD - Agricultural Research for Development | And 6 more authors.
Agricultural Systems | Year: 2011

In communal areas of NE Zimbabwe, feed resources are collectively managed, with herds grazing on grasslands during the rainy season and mainly on crop residues during the dry season, which creates interactions between farmers and competition for organic resources. Addition of crop residues or animal manure is needed to sustain agricultural production on inherently poor soils. Objectives of this study were to assess the effect of village-level interactions on carbon and nutrient flows, and to explore their impact on the long-term productivity of different farm types under climate variability. Crop and cattle management data collected in Murewa Communal area, NE Zimbabwe was used together with a dynamic farm-scale simulation model (NUANCES-FARMSIM) to simulate village-level interactions. Simulations showed that grasslands support most cattle feed intake (c. 75%), and that crop residues produced by non-cattle farmers sustain about 30% of the dry season feed intake. Removal of crop residues (0.3-0.4tCha-1yr-1) from fields of non-cattle farmers resulted in a long-term decrease in crop yields. No-access to crop residues of non-cattle farmers increased soil C modestly and improved yields in the long-term, but not enough to meet household energy requirements. Harvest of grain and removal of most crop residues by grazing cattle caused a long-term decline in soil C stocks for all farm types. The smallest decrease (-0.5tCha-1) was observed for most fertile fields of cattle farmers, who manure their fields. Cattle farmers needed to access 4-10ha of grassland to apply 3t of manure ha-1yr-1. Rainfall variability intensifies crop-livestock interactions increasing competition for biomass to feed livestock (short-term effect) or to rehabilitate soils (long-term effect). Prolonged dry seasons and low availability of crop residues may lead to cattle losses, with negative impact in turn on availability of draught power, affecting area under cultivation in consecutive seasons until farmers re-stock. Increasing mineral fertiliser use concurrently with keeping crop residues in fertile fields and allocating manure to poor fields appears to be a promising strategy to boost crop and cattle productivity at village level. The likelihood of this scenario being implemented depends on availability of fertilisers and decision of farmers to invest in rehabilitating soils to obtain benefits in the long-term. Adaptation options cannot be blind to what occurs beyond field and farm level, because otherwise recommendations from research and development do not fit the local conditions and farmers tend to ignore them. © 2010 Elsevier Ltd.

Woittiez L.S.,Wageningen University | Rufino M.C.,Wageningen University | Rufino M.C.,Center for International Forestry Research | Giller K.E.,Wageningen University | And 2 more authors.
Ecology and Society | Year: 2013

Common lands provide smallholder farmers in Africa with firewood, timber, and feed for livestock, and they are used to complement human diets through the collection of edible nontimber forest products (NTFPs). Farmers have developed coping mechanisms, which they deploy at times of climatic shocks. We aimed to analyze the importance of NTFPs in times of drought and to identify options that could increase the capacity to adapt to climate change. We used participatory techniques, livelihood analysis, observations, and measurements to quantify the use of NTFPs. Communities recognized NTFPs as a mechanism to cope with crop failure. We estimated that indigenous fruits contributed to approximately 20% of the energy intake of wealthier farmers and to approximately 40% of the energy intake of poor farmers in years of inadequate rainfall. Farmers needed to invest a considerable share of their time to collect wild fruits from deforested areas. They recognized that the effectiveness of NTFPs as an adaptation option had become threatened by severe deforestation and by illegal harvesting of fruits by urban traders. Farmers indicated the need to plan future land use to (1) intensify crop production, (2) cultivate trees for firewood, (3) keep orchards of indigenous fruit trees, and (4) improve the quality of grazing lands. Farmers were willing to cultivate trees and to organize communal conservation of indigenous fruits trees. Through participatory exercises, farmers elaborated maps, which were used during land use discussions. The process led to prioritization of pressing land use problems and identification of the support needed: fast-growing trees for firewood, inputs for crop production, knowledge on the cultivation of indigenous fruit trees, and clear regulations and compliance with rules for extraction of NTFPs. Important issues that remain to be addressed are best practices for regeneration and conservation, access rules and implementation, and the understanding and management of competing claims on the common lands. Well-managed communal resources can provide a strong tool to maintain and increase the rural communities' ability to cope with an increasingly variable climate. © 2013 by the author(s).

Nezomba H.,Soil Fertility Consortium For Southern Africa Sofecsa | Mtambanengwe F.,Soil Fertility Consortium For Southern Africa Sofecsa | Chikowo R.,University of Zimbabwe | Mapfumo P.,Soil Fertility Consortium For Southern Africa Sofecsa
Experimental Agriculture | Year: 2015

Research has proved that integrated soil fertility management (ISFM) can increase crop yields at the field and farm scales. However, its uptake by smallholder farmers in Africa is often constrained by lack of technical guidelines on effective starting points and how the different ISFM options can be combined to increase crop productivity on a sustainable basis. A 4-year study was conducted on sandy soils (<10% clay) on smallholder farms in eastern Zimbabwe to assess how sequencing of different ISFM options may lead to incremental gains in soil productivity, enhanced efficiency of resource use, and increase crop yields at field scale. The sequences were primarily based on low-quality organic resources, nitrogen-fixing green manure and grain legumes, and mineral fertilizers. To enable comparison of legume and maize grain yields among treatments, yields were converted to energy (kilocalories) and protein (kg) equivalents. In the first year, 'Manure-start', a cattle manure-based sequence, yielded 3.4 t ha-1 of maize grain compared with 2.5 and 0.4 t ha-1 under a woodland litter-based sequence ('Litter-start') and continuous unfertilized maize control, respectively. The 'Manure-start' produced 12 × 106 kilocalories (kcal); significantly (p < 0.05) out-yielding 'Litter start' and a fertilizer-based sequence ('Fertilizer-start') by 50%. A soyabean-based sequence, 'Soya-start', gave the highest protein production of 720 kg against <450 kg for the other sequencing treatments. In the second year, the sequences yielded an average of 5.7 t ha-1 of maize grain, producing over 19 × 106 kcal and 400 kg of protein. Consequently, the sequences significantly out-performed farmers' designated poor fields by ~ fivefold. In the third year, 'Soya-start' gave the highest maize grain yield of 3.7 t ha-1; translating to 1.5 and 3 times more calories than under farmers' designated rich and poor fields, respectively. In the fourth year, 'Fertilizer-start' produced the highest calories and protein of 14 × 106 kcal and 340 kg, respectively. Cumulatively over 4 years, 'Manure-start' and 'Soya-start' gave the highest calories and protein, out-performing farmers' designated rich and poor fields. Sunnhemp (Crotalaria juncea L.)-based sequences, 'Green-start' and 'Fertilizer-start', recorded the highest gains in plant available soil P of ~ 4 mg kg-1 over the 4-year period. Assessment of P agronomic efficiencies showed significantly more benefits under the ISFM-based sequences than under farmers' designated rich and poor fields. Based on costs of seed, nutrients and labour, 'Soya-start' gave the best net present value over the 4 years, while 'Fertilizer-start' was financially the least attractive. Overall, the ISFM-based sequences were more profitable than fields designated as rich and poor by farmers. We concluded that ISFM-based sequences can provide options for farm-level intensification by different categories of smallholder farmers in Southern Africa. Copyright © Cambridge University Press 2014.

Mapfumo P.,Soil Fertility Consortium For Southern Africa Sofecsa | Mapfumo P.,University of Zimbabwe | Adjei-Nsiah S.,University of Ghana | Mtambanengwe F.,University of Zimbabwe | And 2 more authors.
Environmental Development | Year: 2013

Emerging trends of a changing and increasingly variable climate have introduced new livelihood challenges in rain-fed smallholder agricultural systems that predominate in Sub-Saharan Africa (SSA). The capacity of local farming communities and their institutions to respond to the new and emerging impacts of climate change is often constrained by lack of access to information and improved technologies, as well as poor support mechanisms to promote assimilation of new knowledge. This threatens to heighten vulnerability of the majority of SSA's rural communities who are already facing severe problems of food insecurity and a declining soil resource base. In this paper we use two case studies from Wenchi district in Ghana and Makoni in Zimbabwe to communicate how participatory action research (PAR) methodology, characterised by iterative planning-action-reflection cycles, was coupled with a new concept of field-based farmer learning centres to build adaptive capacity of smallholder farmers to climate change. The study was part of a University of Zimbabwe-led project supported under the Climate Change Adaptation in Africa (CCAA) programme to explore the state of resilience in African smallholder farming. The PAR and learning centre processes enabled communities, local leaders, and extension agents and researchers to establish the, hither to, imperceptible link between poor soil fertility and rising institutional challenges within communities. Institutional conflicts related to land tenure and sharecropping arrangements between migrant farmers and native landowners were addressed in Ghana, while local institutions supporting traditional social safety net mechanisms were revitalized in Zimbabwe. In both cases, it was apparent that farmers faced multiple stresses, at the core of which were poor and declining soil fertility and weakening local institutions. The worsening rainfall distribution and increasing cases of drought are broadening the scope for vulnerability, often driving competing claims and conflicts. PAR was successfully used as an entry point, empowering communities to self-mobilize and self-organize to co-learn and experiment with integrated soil fertility management (ISFM) technologies and other improved farming practices. They realised opportunities for achieving high crop yields and generate surpluses in good years. Strengthening local institutional capacity to revitalise community safety nets proved an essential ingredient for enhancing adaptive capacity of smallholders to climatic shocks. The PAR process was a major driver of effective partnerships among community members, extension, policy makers and researchers, but ensuing success generated a new set of social challenges that could not be addressed within the short timescale of the project. We conclude that PAR was a suitable mechanism for supporting self-organization and co-learning processes among smallholder farmers and their service providers, enabling them to use ISFM technologies and strengthen their local institutions around natural resource management. This revealed the scope for building adaptive capacity of these communities against climate change and variability. © 2012 Elsevier B.V.

Nyikahadzoi K.,University of Zimbabwe | Siziba S.,University of Zimbabwe | Mango N.,International Center for Tropical Agriculture | Mapfumo P.,Soil Fertility Consortium For Southern Africa Sofecsa | And 2 more authors.
Food Security | Year: 2012

The failure of the linear and non-participatory Agricultural Research and Development (ARD) approaches to increase food security among smallholder farmers in sub-Saharan Africa has prompted researchers to introduce an Integrated Agricultural Research for Development (IAR4D) concept. The IAR4D concept uses Innovation Platforms (IPs) to embed agricultural research and development organizations in a network to undertake multidisciplinary and participatory research. This paper uses Zimbabwe as a case study to analyze the relevance of the technologies and innovations that are being promoted by IPs in Zimbabwe to improve food security. Using data collected through the Sub-Saharan Africa Challenge Programme, the paper shows that access to inputs, social capital, productivity enhancing technologies and market information are critical in addressing food security issues among smallholder farmers. The multi-stakeholder partnership forged through IPs should adopt a coordinated approach to provide smallholders with access to these prerequisites for food security. The paper argues that more emphasis should be put on these issues rather than on farm research initiatives whose contribution to food security appears to be less significant. © 2012 Springer Science+Business Media Dordrecht and International Society for Plant Pathology.

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