Cheryl Palm

Multisector intervention to accelerate reductions in child stunting: an observational study from 9 sub-Saharan African countries

BACKGROUND In sub-Saharan Africa, ~ 40% of children <5 y old are stunted, with levels that have remained largely unchanged over the past 2 decades. Although the complex determinants of undernutrition are well recognized, few studies have evaluated strategies that combine nutrition-specific, health-based approaches with food system- and livelihood-based interventions. OBJECTIVE We examined changes in childhood stunting and its determinants after 3 y of exposure to an integrated, multisector intervention and compared these changes with national trends. DESIGN A prospective observational trial was conducted across rural sites in 9 sub-Saharan African countries with baseline levels of childhood stunting >20%. A stratified random sample of households and resident children <2 y old from villages exposed to the program were enrolled in the study. Main outcome measures included principal determinants of undernutrition and childhood stunting, which was defined as a height-for-age z score less than -2. National trends in stunting were generated from demographic and health surveys. RESULTS Three years after the start of the program in 2005-2006, consistent improvements were observed in household food security and diet diversity, whereas coverage with child care and disease-control interventions improved for most outcomes. The prevalence of stunting in children <2 y old at year 3 of the program (2008-2009) was 43% lower (adjusted OR: 0.57; 95% CI: 0.38, 0.83) than at baseline. The average national stunting prevalence for the countries included in the study had remained largely unchanged over the past 2 decades. CONCLUSION These findings provide encouraging evidence that a package of multisector interventions has the potential to produce reductions in childhood stunting.

The Millennium Villages Project: a retrospective, observational, endline evaluation

BACKGROUND The Millennium Villages Project (MVP) was a 10 year, multisector, rural development project, initiated in 2005, operating across ten sites in ten sub-Saharan African countries to achieve the Millennium Development Goals (MDGs). In this study, we aimed to estimate the projects impact, target attainment, and on-site spending. METHODS In this endline evaluation of the MVP, we retrospectively selected comparison villages that best matched the project villages on possible confounding variables. Cross-sectional survey data on 40 outcomes of interest were collected from both the project and the comparison villages in 2015. Using these data, as well as on-site spending data collected during the project, we estimated project impacts as differences in outcomes between the project and comparison villages; target attainment as differences between project outcomes and prespecified targets; and on-site spending as expenditures reported by communities, donors, governments, and the project. Spending data were not collected in the comparison villages. FINDINGS Averaged across the ten project sites, we found that impact estimates for 30 of 40 outcomes were significant (95% uncertainty intervals [UIs] for these outcomes excluded zero) and favoured the project villages. In particular, substantial effects were seen in agriculture and health, in which some outcomes were roughly one SD better in the project villages than in the comparison villages. The project was estimated to have no significant impact on the consumption-based measures of poverty, but a significant favourable impact on an index of asset ownership. Impacts on nutrition and education outcomes were often inconclusive (95% UIs included zero). Averaging across outcomes within categories, the project had significant favourable impacts on agriculture, nutrition, education, child health, maternal health, HIV and malaria, and water and sanitation. A third of the targets were met in the project sites. Total on-site spending decreased from US

Nonlinear response of nitric oxide fluxes to fertilizer inputs and the impacts of agricultural intensification on tropospheric ozone pollution in Kenya

132 per person in the first half of the project (of which

Targeting Sustainable Intensification of Maize-Based Agriculture in East Africa:

66 was from the MVP) to

Limited potential of no-till agriculture for climate change mitigation

109 per person in the second half of the project (of which

Evaluating agricultural trade-offs in the age of sustainable development

25 was from the MVP). INTERPRETATION The MVP had favourable impacts on outcomes in all MDG areas, consistent with an integrated rural development approach. The greatest effects were in agriculture and health, suggesting support for the projects emphasis on agriculture and health systems strengthening. The project conclusively met one third of its targets. FUNDING The Open Society Foundations, the Islamic Development Bank, and the governments of Japan, South Korea, Mali, Senegal, and Uganda.

Linking ecosystem services and human well-being

Abstract Crop yields in sub‐Saharan Africa remain stagnant at 1 ton ha−1, and 260 million people lack access to adequate food resources. Order‐of‐magnitude increases in fertilizer use are seen as a critical step in attaining food security. This increase represents an unprecedented input of nitrogen (N) to African ecosystems and will likely be accompanied by increased soil emissions of nitric oxide (NO). NO is a precursor to tropospheric ozone, an air pollutant and greenhouse gas. Emissions of NO from soils occur primarily during denitrification and nitrification, and N input rates are a key determinant of emission rates. We established experimental maize plots in western Kenya to allow us to quantify the response function relating NO flux to N input rate during the main 2011 and 2012 growing seasons. NO emissions followed a sigmoid response to fertilizer inputs and have emission factors under 1% for the roughly two‐month measurement period in each year, although linear and step relationships could not be excluded in 2011. At fertilization rates above 100 kg N ha−1, NO emissions increased without a concomitant increase in yields. We used the geos‐chem chemical transport model to evaluate local impacts of increased NO emissions on tropospheric ozone concentrations. Mean 4‐hour afternoon tropospheric ozone concentrations in Western Kenya increased by up to roughly 2.63 ppbv under fertilization rates of 150 kg N ha−1 or higher. Using AOT40, a metric for assessing crop damage from ozone, we find that the increased ozone concentrations result in an increase in AOT40 exposure of approximately 110 ppbh for inputs of 150 kg N ha−1 during the March–April–May crop growing season, compared with unfertilized simulations, with negligible impacts on crop productivity. Our results suggest that it may be possible to manage Kenyan agricultural systems for high yields while avoiding substantial impacts on air quality. &NA; Fertilizer use is expected to increase by more than an order of magnitude in sub‐Saharan Africa, to increase food production and reduce food insecurity. We measured emissions of nitric oxide, a precursor to tropospheric ozone pollution, over 2 years from experimental maize plots in western Kenya to understand how agricultural intensification may affect air quality and to quantify the relationship between nitrogen inputs and NO emissions. We found evidence that nitric oxide emissions increase as a sigmoidal function of the rate of nitrogen additions, with the highest emissions occurring above recommended fertilization rates. Using an atmospheric chemical transport model, we find that changes in tropospheric ozone pollution driven by increased fertilizer‐induced nitric oxide emissions are unlikely to negatively impact crop production in western Kenya. Figure. No caption available.

Reply to 'No-till agriculture and climate change mitigation'

Agricultural intensification in Sub-Saharan Africa has the chance to increase yields and food security while minimizing environmental contamination and protecting remaining native ecosystems. Targeting intensification to areas of high production potential including clayey, deep tropical soils on gently sloping lands will reduce leaching and runoff of nitrogen into water bodies. This holds particularly for rates of nitrogen fertilizer applications of less than 150 N ha−1 yr−1 rates at which nitrous oxide emissions also remain low. Overlays of maps of maize production potential, soil properties, and topography for East Africa indicate almost half of that area has high production potential and a third of that is on favorable soils. More than 70% of this area identified for targeting is already in cropland, thus reducing the need to clear additional native ecosystems. Targeting intensification must also include factors such as climate and seasonality. Incorporating results from field studies of agricultural impacts, assessing these impacts at larger scales, and developing planning maps with national partners and other stakeholders are key steps toward promoting increased crop production while minimizing environmental consequences.