The Experts below are selected from a list of 99 Experts worldwide ranked by ideXlab platform
Frederi Viens - One of the best experts on this subject based on the ideXlab platform.
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a bayesian analysis of longitudinal Farm surveys in central malawi reveals yield determinants and site specific management strategies
PLOS ONE, 2019Co-Authors: Han Wang, Sieglinde S Snapp, Monica Fisher, Frederi ViensAbstract:Understanding the challenges to increasing maize productivity in sub-Saharan Africa, especially agronomic factors that reduce on-Farm Crop yield, has important implications for policies to reduce national and global food insecurity. Previous research on the maize yield gap has tended to emphasize the size of the gap (theoretical vs. achievable yields), rather than what determines maize yield in specific contexts. As a result, there is insufficient evidence on the key agronomic and environmental factors that influence maize yield in a smallholder Farm environment. In this study, we implemented a Bayesian analysis with plot-level longitudinal household survey data covering 1,197 plots and 320 Farms in Central Malawi. Households were interviewed and monitored three times per year, in 2015 and 2016, to document Farmer management practices and seasonal rainfall, and direct measurements were taken of plant and soil characteristics to quantify impact on plot-level maize yield stability. The results revealed a high positive association between a leaf chlorophyll indicator and maize yield, with significance levels exceeding 95% Bayesian credibility at all sites and a regression coefficient posterior mean from 28% to 42% on a relative scale. A parasitic weed, Striga asiatica, was the variable most consistently negatively associated with maize yield, exceeding 95% credibility in most cases, of high intensity, with regression means ranging from 23% to 38% on a relative scale. The influence of rainfall, either directly or indirectly, varied by site and season. We conclude that the factors preventing Striga infestation and enhancing nitrogen fertility will lead to higher maize yield in Malawi. To improve plant nitrogen status, fertilizer was effective at higher productivity sites, whereas soil carbon and organic inputs were important at marginal sites. Uniquely, a Bayesian approach allowed differentiation of response by site for a relatively modest sample size study (given the complexity of Farm environments and management practices). Considering the biophysical constraints, our findings highlight management strategies for Crop yields, and point towards area-specific recommendations for nitrogen management and Crop yield.
Andrew D Jones - One of the best experts on this subject based on the ideXlab platform.
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critical review of the emerging research evidence on agricultural biodiversity diet diversity and nutritional status in low and middle income countries
Nutrition Reviews, 2017Co-Authors: Andrew D JonesAbstract:The declining diversity of agricultural production and food supplies worldwide may have important implications for global diets. The primary objective of this review is to assess the nature and magnitude of the associations of agricultural biodiversity with diet quality and anthropometric outcomes in low- and middle-income countries. A comprehensive review of 5 databases using a priori exclusion criteria and application of a systematic, qualitative analysis to the findings of identified studies revealed that agricultural biodiversity has a small but consistent association with more diverse household- and individual-level diets, although the magnitude of this association varies with the extent of existing diversification of Farms. Greater on-Farm Crop species richness is also associated with small, positive increments in young child linear stature. Agricultural diversification may contribute to diversified diets through both subsistence- and income-generating pathways and may be an important strategy for improving diets and nutrition outcomes in low- and middle-income countries. Six research priorities for future studies of the influence of agricultural biodiversity on nutrition outcomes are identified based on gaps in the research literature.
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on Farm Crop species richness is associated with household diet diversity and quality in subsistence and market oriented Farming households in malawi
Journal of Nutrition, 2017Co-Authors: Andrew D JonesAbstract:BACKGROUND On-Farm Crop species richness (CSR) may be important for maintaining the diversity and quality of diets of smallholder Farming households. OBJECTIVES The objectives of this study were to 1) determine the association of CSR with the diversity and quality of household diets in Malawi and 2) assess hypothesized mechanisms for this association via both subsistence- and market-oriented pathways. METHODS Longitudinal data were assessed from nationally representative household surveys in Malawi between 2010 and 2013 (n = 3000 households). A household diet diversity score (DDS) and daily intake per adult equivalent of energy, protein, iron, vitamin A, and zinc were calculated from 7-d household consumption data. CSR was calculated from plot-level data on all Crops cultivated during the 2009-2010 and 2012-2013 agricultural seasons in Malawi. Adjusted generalized estimating equations were used to assess the longitudinal relation of CSR with household diet quality and diversity. RESULTS CSR was positively associated with DDS (β: 0.08; 95% CI: 0.06, 0.12; P < 0.001), as well as daily intake per adult equivalent of energy (kilocalories) (β: 41.6; 95% CI: 20.9, 62.2; P < 0.001), protein (grams) (β: 1.78; 95% CI: 0.80, 2.75; P < 0.001), iron (milligrams) (β: 0.30; 95% CI: 0.16, 0.44; P < 0.001), vitamin A (micrograms of retinol activity equivalent) (β: 25.8; 95% CI: 12.7, 38.9; P < 0.001), and zinc (milligrams) (β: 0.26; 95% CI: 0.13, 0.38; P < 0.001). Neither proportion of harvest sold nor distance to nearest population center modified the relation between CSR and household diet diversity or quality (P ≥ 0.05). Households with greater CSR were more commercially oriented (least-squares mean proportion of harvest sold ± SE, highest tertile of CSR: 17.1 ± 0.52; lowest tertile of CSR: 8.92 ± 1.09) (P < 0.05). CONCLUSION Promoting on-Farm CSR may be a beneficial strategy for simultaneously supporting enhanced diet quality and diversity while also creating opportunities for smallholder Farmers to engage with markets in subsistence agricultural contexts.
Han Wang - One of the best experts on this subject based on the ideXlab platform.
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a bayesian analysis of longitudinal Farm surveys in central malawi reveals yield determinants and site specific management strategies
PLOS ONE, 2019Co-Authors: Han Wang, Sieglinde S Snapp, Monica Fisher, Frederi ViensAbstract:Understanding the challenges to increasing maize productivity in sub-Saharan Africa, especially agronomic factors that reduce on-Farm Crop yield, has important implications for policies to reduce national and global food insecurity. Previous research on the maize yield gap has tended to emphasize the size of the gap (theoretical vs. achievable yields), rather than what determines maize yield in specific contexts. As a result, there is insufficient evidence on the key agronomic and environmental factors that influence maize yield in a smallholder Farm environment. In this study, we implemented a Bayesian analysis with plot-level longitudinal household survey data covering 1,197 plots and 320 Farms in Central Malawi. Households were interviewed and monitored three times per year, in 2015 and 2016, to document Farmer management practices and seasonal rainfall, and direct measurements were taken of plant and soil characteristics to quantify impact on plot-level maize yield stability. The results revealed a high positive association between a leaf chlorophyll indicator and maize yield, with significance levels exceeding 95% Bayesian credibility at all sites and a regression coefficient posterior mean from 28% to 42% on a relative scale. A parasitic weed, Striga asiatica, was the variable most consistently negatively associated with maize yield, exceeding 95% credibility in most cases, of high intensity, with regression means ranging from 23% to 38% on a relative scale. The influence of rainfall, either directly or indirectly, varied by site and season. We conclude that the factors preventing Striga infestation and enhancing nitrogen fertility will lead to higher maize yield in Malawi. To improve plant nitrogen status, fertilizer was effective at higher productivity sites, whereas soil carbon and organic inputs were important at marginal sites. Uniquely, a Bayesian approach allowed differentiation of response by site for a relatively modest sample size study (given the complexity of Farm environments and management practices). Considering the biophysical constraints, our findings highlight management strategies for Crop yields, and point towards area-specific recommendations for nitrogen management and Crop yield.
Buckley Ryan - One of the best experts on this subject based on the ideXlab platform.
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Agroecological practices supporting food production and reducing food insecurity in developing countries: A study on scientific literature in 17 countries
'Publications Office of the European Union', 2020Co-Authors: Paracchini Maria-luisa, Justes Eric, Wezel Alexander, Zingari Pier Carlo, Kahane Remi, Madsen Sidney, Scopel Eric, HÉraut Antonin, BhÉrer-breton Paul, Buckley RyanAbstract:This report represents the initial effort to structure existing knowledge about agroecology as Farming and food system in support of the EC Knowledge Centre on Food and Nutrition Security (https://ec.europa.eu/knowledge4policy/global-food-nutrition-security_en). Scientific literature has been screened on a selection of developing countries in which food and nutrition security and sustainable agriculture represent a focal sector for EU intervention (Benin, Burkina Faso, Cuba, Ethiopia, Ghana, Guatemala, Kenya, Lao PDR, Madagascar, Malawi, Mali, Nicaragua, Niger, Senegal, Tanzania, Togo, Zimbabwe). In total, 172 documents hae been synthesised, a country brief has been prepared for each investigated country, and some general conclusions have been drawn. Overall, the majority of analysed publications focuses on small scale, extensive Farming systems that produce food at subsistence levels and for sale on local markets. This includes smallholder Farming producing staple Crops (millet, sorghum, yam, etc.) or vegetable gardening for local markets. The agroecological practices that are mostly studied are: agroforestry, interCropping (or mixed Cropping), introduction of legumes in rotations, soil and water conservation practices (mulching, return of Crop residues, zaï holes etc.), use of animal manure, biocontrol methods to mitigate chemical pesticide use. At least 50% of the analysed papers report a positive contribution of agroecological practices to food security, mostly due to improved yields and/or a better economic situation of producers. The improvement of soil quality is key to improve yields and consequently income and food security; this can be achieved using various practices including the use of residue mulch from tree leaves in agroforestry, as well as Crop mixtures or interCropping and longer more diversified Crop rotations. Moreover, higher on-Farm Crop species diversity often results in more diversified diets. Diversified Crop systems, including the introduction of agroforestry, improves household nutritional status and has positive links to better health conditions. On the other hand, the lack of access to inputs is an important limitation to the improvement of soil fertility (manure, mineral fertilizer, leaf litter, etc.), which remains a major hindrance for food security. The agroecological cultivation of cash Crops, post-harvest practices and Crop-livestock integration were overall lacking in the scientific analyses, as well as the assessments of fully agroecological systems compared to individual agroecological practices or groups of practices. The report identifies three factors required for the substantial development of agroecology at the Farm level: more financial support from the government, greater scientific knowledge on novel agroecological practices, and a higher market value for agroecological products.JRC.D.5-Food Securit
Buckley R. - One of the best experts on this subject based on the ideXlab platform.
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Agroecological practices supporting food production and reducing food insecurity in developing countries. A study on scientific literature in 17 countries
'Publications Office of the European Union', 2020Co-Authors: Paracchini M.l., Justes Eric, Wezel Alexander, Zingari Pier Carlo, Kahane Remi, Scopel Eric, Madsen S., Hérault Antonin, Bhérer-breton P., Buckley R.Abstract:This report represents the initial effort to structure existing knowledge about agroecology as Farming and food system in support of the EC Knowledge Centre on Food and Nutrition Security (https://ec.europa.eu/knowledge4policy/global-food-nutrition-security_en). Scientific literature has been screened on a selection of developing countries in which food and nutrition security and sustainable agriculture represent a focal sector for EU intervention (Benin, Burkina Faso, Cuba, Ethiopia, Ghana, Guatemala, Kenya, Lao PDR, Madagascar, Malawi, Mali, Nicaragua, Niger, Senegal, Tanzania, Togo, Zimbabwe). In total, 172 documents have been synthesised, a country brief has been prepared for each investigated country, and some general conclusions have been drawn. Overall, the majority of analysed publications focuses on small scale, extensive Farming systems that produce food at subsistence levels and for sale on local markets. This includes smallholder Farming producing staple Crops (millet, sorghum, yam, etc.) or vegetable gardening for local markets. The agroecological practices that are mostly studied are: agroforestry, interCropping (or mixed Cropping), introduction of legumes in rotations, soil and water conservation practices (mulching, return of Crop residues, zaï holes etc.), use of animal manure, biocontrol methods to mitigate chemical pesticide use. At least 50% of the analysed papers report a positive contribution of agroecological practices to food security, mostly due to improved yields and/or a better economic situation of producers. The improvement of soil quality is key to improve yields and consequently income and food security; this can be achieved using various practices including the use of residue mulch from tree leaves in agroforestry, as well as Crop mixtures or interCropping and longer more diversified Crop rotations. Moreover, higher on-Farm Crop species diversity often results in more diversified diets. Diversified Crop systems, including the introduction of agroforestry, improve household nutritional status and have positive links to better health conditions. On the other hand, the lack of access to inputs is an important limitation to the improvement of soil fertility (manure, mineral fertilizer, leaf litter, etc.), which remains a major hindrance for food security. The agroecological cultivation of cash Crops, post-harvest practices and Crop-livestock integration were overall lacking in the scientific analyses, as well as the assessments of fully agroecological systems compared to individual agroecological practices or groups of practices. Increasing financial support from the government, of scientific knowledge on practices alternative to what currently applied, higher market value for agroecological products have been identified as important factors to be improved for the development of agroecology at the Farm level
