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Autor: Sieglinde Snapp
Advancing the science and practice of ecological nutrient management for smallholder farmers
Sieglinde Snapp (2022)
Artículo
CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGROECOLOGY DEGRADATION NUTRIENT CYCLES NUTRIENT USE EFFICIENCY SOIL ORGANIC MATTER SMALLHOLDERS
Fighting food, fertilizer, and the climate crisis in Africa through targeted nitrogen management
Tek Sapkota Sieglinde Snapp (2022)
Objeto de congreso
CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA FOOD INSECURITY NITROGEN FERTILIZERS RICE WHEAT MAIZE NUTRIENT MANAGEMENT
Tek Sapkota Sieglinde Snapp (2022)
Objeto de congreso
CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CEREAL PRODUCTS PRODUCTION SYSTEMS CEREALS NITROGEN RICE WHEAT MAIZE
Regis Chikowo Sieglinde Snapp (2023)
Crop diversification with grain legumes has been advocated as a means to increase agroecological resilience, diversify livelihoods, boost household nutrition, and enhance soil health and fertility in cereal-based cropping systems in sub-Saharan Africa and around the world. Soil organic carbon (SOC) is a primary indicator of soil health and there is limited data regarding SOC pools and grain legume diversification on smallholder farms where soils are often marginal. In Malawi, a range of legume diversification options are under investigation, including rotations and a doubled-up legume rotation (DLR) system in which two compatible legumes are intercropped and then rotated with a cereal. The impact of the DLR system on SOC has not yet been determined, and there is a lack of evidence regarding SOC status over a gradient of simple to complex grain legume diversified systems. We address this knowledge gap by evaluating these systems in comparison to continuous sole maize (Zea mays L.) at three on-farm trial sites in central Malawi. After six years of trial establishment, we measured SOC in bulk soils and aggregate fractions and in faster cycling SOC pools that respond more rapidly to management practices, including water extractable organic carbon (WEOC), particulate organic matter carbon (POM-C), potentially mineralizable carbon (C), and macroaggregate C. Cropping treatment differences were not seen in bulk SOC or total N, but they were apparent in SOC pools with a shorter turnover time. The DLR system of intercropped pigeonpea (Cajanus cajan (L.) Millsp.) and groundnut (Arachis hypogaea L.) rotated with maize had higher WEOC, POM-C, potentially mineralizable C, macroaggregate and microaggregate C values than continuous maize. Of the single legume rotations, the pigeonpea-maize rotation had more mineralizable C and microaggregate C compared to continuous maize, while the groundnut-maize rotation had similar C values to the maize system. Overall, this study shows the potential for crop rotations diversified with grain legumes to enhance C in management sensitive SOC pools, and it is one of the first reports to show this effect on smallholder farm sites.
Artículo
Crop Diversification Water Extractable Organic Carbon CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA DIVERSIFICATION LEGUMES PARTICULATE ORGANIC MATTER SOIL ORGANIC CARBON
Sieglinde Snapp Yodit Kebede Eva Wollenberg (2023)
A critical question is whether agroecology can promote climate change mitigation and adaptation outcomes without compromising food security. We assessed the outcomes of smallholder agricultural systems and practices in low- and middle-income countries (LMICs) against 35 mitigation, adaptation, and yield indicators by reviewing 50 articles with 77 cases of agroecological treatments relative to a baseline of conventional practices. Crop yields were higher for 63% of cases reporting yields. Crop diversity, income diversity, net income, reduced income variability, nutrient regulation, and reduced pest infestation, indicators of adaptative capacity, were associated with 70% or more of cases. Limited information on climate change mitigation, such as greenhouse gas emissions and carbon sequestration impacts, was available. Overall, the evidence indicates that use of organic nutrient sources, diversifying systems with legumes and integrated pest management lead to climate change adaptation in multiple contexts. Landscape mosaics, biological control (e.g., enhancement of beneficial organisms) and field sanitation measures do not yet have sufficient evidence based on this review. Widespread adoption of agroecological practices and system transformations shows promise to contribute to climate change services and food security in LMICs. Gaps in adaptation and mitigation strategies and areas for policy and research interventions are finally discussed.
Artículo
CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CLIMATE CHANGE CROPS FOOD SUPPLY GAS EMISSIONS GREENHOUSE GASES FARMING SYSTEMS AGROECOLOGY FOOD SECURITY LESS FAVOURED AREAS SMALLHOLDERS YIELDS NUTRIENTS BIOLOGICAL PEST CONTROL CARBON SEQUESTRATION LEGUMES
Khondoker Mottaleb Gideon Kruseman Sieglinde Snapp (2022)
Violent conflict is a major cause of acute food crises. In 2021, at least 155 million people in 10 countries were severely food insecure and eight of those countries were experiencing armed conflict. On February 24, 2022, an armed conflict between Russian Federation (Russia) and Ukraine escalated. As Russia and Ukraine are major wheat exporters, this will aggravate the already precarious food security situation in many developing countries by disrupting wheat production and export and by accelerating price hikes in import-dependent developing countries. This study examines the potential impacts of this ongoing armed conflict between Russia and Ukraine on wheat price, consumption, and calorie intake from wheat. In doing so, it applies the conditional mixed process estimation procedure using information collected from 163 countries and territories for the years 2016–2019 from online database of the Food and Agriculture Organization of the United Nations (FAO). The study shows that, on average, a 1% decrease in the global wheat trade could increase the producers' price of wheat by 1.1%, and a 1% increase in the producers' price could reduce the yearly per capita wheat consumption by 0.59%, daily calorie intake by 0.54% and protein intake by 0.64% in the sampled countries. Based on this, the study demonstrates that a 50% reduction in wheat exports by Russia and Ukraine could increase the producers’ price of wheat by 15%, which would induce a reduction in wheat consumption and dietary energy intake by at least 8%. Since wheat export has reduced from both Russia and Ukraine, to avoid a food crisis in developing countries, policies are suggested, including near term improvement of domestic wheat production by promoting improved agronomic practices to close yield gaps to meet a substantial portion of wheat self-sufficiency goals. In the long run, countries in Africa, East Asia and South America can explore expanding wheat into new land area. International donor agencies can play a key role in supporting the ongoing wheat research and development activities.
Artículo
Export-Import CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA ARMED CONFLICTS CALORIES CONSUMPTION ELASTICITY FOOD SECURITY PRICES PRODUCTION WHEAT
Strategies steering intensification pathways of farmers in central Malawi
Carl Timler Jeroen Groot Sieglinde Snapp Pablo Tittonell (2023)
Smallholder farmers face many challenges to improve their livelihoods and food security. Intensification of agricultural production can help to achieve these goals. Yet farmers are highly heterogenous in their strategies towards intensification, potentially following unsustainable intensification pathways. Using Q Methodology, we ascertain different strategies regarding farm improvement and intensification of smallholder farmers in the Dedza and Ntcheu Extension Planning Areas in Central Malawi. These strategies were associated to coherent sequential choices as expressed in “managerial intensification pathways” (MIPs). Three main strategies emerged: Seed Saving Peasants, Aspirant Modern Farmers and Entrepreneurial Business(wo)men. These were subsequently linked to four MIPs. Seed Saving Peasants focus strongly on local seed systems and post-harvest protection of grains, but also allocate more labour to improving crop residue use and manure quality, thus pointing to a labour-oriented MIP. Aspirant Modern Farmers willingly adopt hybrid seeds and inorganic fertilizers but require more extension support; these farmers follow a technology-oriented MIP. Entrepreneurial Business(wo)men are early adopters of new technologies and benefit from improved access to market information and suppliers of new technologies and follow a sustainable technology-based or techno-ecological intensification pathway. This study shows that strongly contrasting perspectives on intensification exist among smallholders and it is expected that their preferred intensification choices will have diverging impacts on the sustainability of their farms. A diversity of extension, advice and incentive instruments will be needed to support farmer decision making towards sustainably intensified farms.
Artículo
Smallholder Farmers Q Methodology CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA SMALLHOLDERS STRATEGIES SUSTAINABLE INTENSIFICATION
Leah Mungai Joseph Messina Leo Zulu Jiaguo Qi Sieglinde Snapp (2022)
Artículo
Multilayer Perceptrons CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA AGRICULTURE LAND USE POPULATION SATELLITE IMAGERY TEXTURE LAND COVER NEURAL NETWORKS REMOTE SENSING
Redesigning crop varieties to win the race between climate change and food security
Kevin Pixley Jill Cairns Santiago Lopez-Ridaura Chris Ojiewo Baloua Nébié Godfrey Asea Biswanath Das Benoit Joseph Batieno Clare Mukankusi Sarah Hearne Kanwarpal Dhugga Sieglinde Snapp Ernesto Adair Zepeda Villarreal (2023)
Artículo
Crop Breeding Expert Survey CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CLIMATE CHANGE CROPPING SYSTEMS FOOD SECURITY CROPS