Smallholder responses to climate anomalies in rural Uganda

Gender differentials on productivity of rice farmers in south western Nigeria: An Oaxaca-Blinder decomposition approach

Gender differences in productivity are one of the major obstacles impeding the development of agriculture in Africa and Nigerian particularly. With the Oaxaca-Blinder (OB) and exogenous switching treatment regression (ESTER) models, this study investigates the causes of the productivity differences among 360 sampled rice farmers in Nigeria as well as gender inequality in agricultural productivity. The findings showed that there is an inequalities between men and women, which contributes to a gender productivity gap of almost 29 % in favour of men. As a result, plots managed by women are 29 % less productive than plots handled by men. The analysis of the factors influencing gender variations in production reveals that the endowment component, which accounts for 15 % of the productivity gap, is significantly influenced by marital status, education, farm size, and access to market information. Similarly, the ESTER results show that the rice yield of FHHs would have decreased by 25.41 kg/ha (a 1.02 % reduction) if they had been assigned the same returns to the observed features of MHHs. This difference is significant at the 1 % level. Thus, the findings imply that the FHHs are not at a yield disadvantage when compared to the MHHs. Therefore, it can be said that there are gender productivity disparities in the Nigerian agricultural industry. As such, policy interventions aimed at empowering women must take these disparities into consideration as well as the causes that contribute to them. Overall, the results demonstrate that although policymakers and their development partners can use improved technologies to increase MHH and FHH yields, reducing the difference in market linkages is necessary to close the gender gap in rice productivity and provide FHHs with equal access to the market.

"Measuring the Environmental Context of Child Growth in Burkina Faso"

Child growth failure, as indicated by low height-for-age z-scores (HAZ), is an important metric of health, social inequality, and food insecurity. Understanding the environmental pathways to this outcome can provide insight into how to prevent it. While other studies have examined the environmental determinants of HAZ, there is no agreed upon best-practices approach to measure the environmental context of this outcome. From this literature, we derive a large set of potential environmental predictors and specifications including temperature and precipitation levels, anomalies, and counts as well as vegetation anomalies and trends, which we include using linear, nonlinear, and interactive specifications. We compare these measures and specifications using four rounds of DHS survey data from Burkina Faso and a large set of fixed effects regression models, focusing on exposures from the time of conception through the second year of life and relying on joint hypothesis tests and goodness-of-fit measures to determine which approach best explains HAZ. Our analysis reveals that nonlinear and interactive transformations of climate anomalies, as opposed to climate levels or vegetation indices, provide the best explanation of child growth failure. These results underline the complex and nonlinear pathways through which climate change affects child health and should motivate climate-health researchers to more broadly adopt measures and specifications that capture these pathways.

Impact of air pollution on stunting among children in Africa

BACKGROUND

Undernutrition is a global public health crisis, causing nearly half of deaths for children under age 5 years. Little is known regarding the impact of air pollution in-utero and early childhood on health outcomes related to undernutrition. The aim of our study is to evaluate the association of prenatal and early-life exposure to PM_2.5 and child malnutrition as captured by the height-for-age z-score (HAZ), and stunting in 32 countries in Africa. We also evaluated critical windows of susceptibility during pregnancy to each environmental risk.

METHODS

We linked nationally representative anthropometric data from 58 Demographic and Health Surveys (DHS) (n = 264,207 children < 5 years of age) with the average in-utero PM_2.5 concentrations derived from satellite imagery. We then estimated associations between PM_2.5 and stunting and HAZ after controlling for child, mother and household factors, and trends in time and seasonality.

RESULTS

We observed lower HAZ and increased stunting with higher in-utero PM_2.5 exposure, with statistically significant associations observed for stunting (OR: 1.016 (95% CI: 1.002, 1.030), for a 10 μg/m³ increase). The associations observed were robust to various model specifications. Wald tests revealed that sex, wealth quintile and urban/rural were not significant effect modifiers of these associations. When evaluating associations between trimester-specific PM_2.5 levels, we observed that associations between PM_2.5 and stunting was the largest.

CONCLUSIONS

This is one of the first studies for the African continent to investigate in-utero and early-life exposure to PM_2.5 is an important marker of childhood undernutrition. Our results highlight that PM_2.5 concentrations need to be urgently mitigated to help address undernutrition in children on the continent.

Exploring linkages between drought and HIV treatment adherence in Africa: a systematic review

Climate change is directly and indirectly linked to human health, including through access to treatment and care. Our systematic review presents a systems understanding of the nexus between drought and antiretroviral therapy (ART) adherence in HIV-positive individuals in the African setting. Narrative synthesis of 111 studies retrieved from Web of Science, PubMed/MEDLINE, and PsycINFO suggests that livelihoods and economic conditions, comorbidities and ART regimens, human mobility, and psychobehavioural dispositions and support systems interact in complex ways in the drought-ART adherence nexus in Africa. Economic and livelihood-related challenges appear to impose the strongest impact on human interactions, actions, and systems that culminate in non-adherence. Indeed, the complex pathways identified by our systems approach emphasise the need for more integrated research approaches to understanding this phenomenon and developing interventions.

Smallholder Farmer Engagement in Citizen Science for Varietal Diversification Enhances Adaptive Capacity and Productivity in Bihar, India

There is evidence that in many situations the use of a diverse set of two or more crop varieties in the field has benefits for production. The benefits of varietal diversification include lower crop disease incidence, higher productivity, and lower yield variability. Targeted interventions could increase varietal diversity where smallholder farmers lack the knowledge and access to seeds needed to diversify their varieties. Innovations based on crowdsourced citizen science make it possible to involve a large number of households in farmer participatory varietal selection. This study analyses varietal diversification in Bihar, India, focusing on the effects of the largest citizen science-based intervention to date, involving 25,000 farmers and 47,000 plots * seasons. The study examines if an increase in the varietal diversity of major staple crops, namely wheat and rice, under real farming conditions contributed to: (1) crop productivity and (2) the ability of households to recover from agricultural production shocks. We used the Rural Household Multi-Indicator Survey (RHoMIS) as a survey tool for rapid characterization of households and the sustainable rural livelihoods framework to understand the potential multiple interactions that are activated within the system by the intervention. We found that an increase in varietal diversification produced livelihood benefits in terms of crop productivity and the ability of households to recover from the occurrence agricultural shocks. Finally, outcomes highlight the effectiveness of development programmes aimed at strengthening rural livelihoods through participatory approaches and use of local crop varietal diversity.

Population Responses to Environmental Change: Looking Back, Looking Forward

Over the past two decades, population researchers have engaged in a far-reaching and productive program of research on demographic responses to changes in the natural environment. This essay "looks back" to the origins of these developments, identifying pivotal agenda-setting moments in the 1990s and tracing the impact on contemporary research. The essay also "looks forward" to identify critical gaps and challenges that remain to be addressed and to set an agenda for future research on population responses to environmental change. It recommends that the multidimensionality of environmental contexts and change be fully embraced, long run as well as short term effects be investigated, variability in the effects of environmental change in relation to social institutions, policy implementation, and environmental context be examined, movement between contexts as well as change in situ as sources of environmental change be considered, and interconnections among demographic processes in response to environmental change be explored. Taking these steps will position demographers to contribute significantly to a larger and deeper understanding of environmental change and its consequences, locally, regionally, and globally.

Climate Variability and Child Nutrition: Findings from Sub-Saharan Africa

Climatic variability affects many underlying determinants of child malnutrition, including food availability, access, and utilization. Evidence of the effects of changing temperatures and precipitation on children's nutritional status nonetheless remains limited. Research addressing this knowledge gap is merited given the short- and long-run consequences of malnutrition. We address this issue by estimating the effects of temperature and precipitation anomalies on the weight and wasting status of children ages 0-59 months across 16 countries in sub-Saharan Africa. Linear regression models show that high temperatures and low precipitation are associated with reductions in child weight, and that high temperatures also lead to increased risk of wasting. We find little evidence of substantively meaningful differences in these effects across sub-populations of interest. Our results underscore the vulnerability of young children to climatic variability and its second-order economic and epidemiological effects. The study also highlights the corresponding need to design and assess interventions to effectively mitigate these impacts.

Climate anomalies, land degradation and rural out-migration in Uganda

Globally, rural livelihoods are increasingly challenged by the dual threats of land degradation and climate change. These issues are of particular concern in sub-Saharan Africa, where land degradation is believed to be severe and where climate change will bring higher temperatures and shifts in rainfall. To date, however, we know little about the relative effects of these various potential environmental stressors on migration. To examine these processes, we link longitudinal data from 850 Ugandan households with environmental data on soils, forests, and climate, and then analyze these data using approaches that account for potential spatial and temporal confounders. Our findings reveal that climate anomalies, rather than land degradation, are the primary contributor to environmental migration in Uganda, with heat stress of particular importance. Short hot spells increase temporary migration, an element of a diversified household livelihood strategy, while long-term heat stress induces permanent migration through an agricultural livelihoods pathway.

How does fossil energy abundance affect China's economic growth and CO2 emissions?

The paper uses the nonparametric additive regression model with data- driven characteristics to investigate the impact of fossil energy abundance on China's economic growth and carbon dioxide (CO₂) emissions. The results show that the effect of fossil energy abundance on economic growth shows an inverted "U-shaped" pattern in the eastern region, due to the changes in coal mining, oil processing, and coking investments. On the contrary, fossil energy abundance exerts a positive "U-shaped" nonlinear effect on economic growth in the central region. This indicates that in the early stages fossil energy abundance did not play a role in promoting economic growth, and its driving effect was only prominent in the later stages. In addition, fossil energy abundance generates a positive "U-shaped" impact on CO₂ emissions in the eastern and central regions, because of the changes in coal and oil consumption at different stages. However, fossil energy abundance has an inverted "U-shaped" nonlinear effect on CO₂ emissions in the western region, on account of the phase difference in the production and consumption of natural gas and oil.

Salt-tolerant rice variety adoption in the Mekong River Delta: Farmer adaptation to sea-level rise

Rice production in the Mekong River Delta of Vietnam (MRD) is endangered by sea-level rise and an associated increase in the incidence of salinity intrusion. This paper examines the diffusion of salt tolerant rice varieties in the MRD that were promoted through Consortium for Unfavorable Rice Environments (CURE) activities. Factors associated with adoption of CURE-related varieties are estimated using a random utilty model and a dataset of 800 farm households with rice fields in salinity prone areas of the MRD. Results suggest that there has been widespread adoption of CURE-related varieties in salinity-prone areas. Further, multivariate analysis reveals that environment and location characteristics, rather than household characteristics, are the most important determinants of adoption. In particular, CURE-related varieties are more likely to be adopted in high-salinity-risk areas that are not protected by salinity barrier gates. Neighbhors’ adoption decisions also strongly influence household decisions to adopt CURE-related varieties. The contracting of mechanization, particularly for land preparation and harvest, requires the coordination of village households in timing of planting, harvest and varietal duration. This coordination appears to extend to choice of CURE-related varieties. Finally, CURE-related varieties and other varieties generate similar net revenues in a year with low salinity exposure, suggesting that CURE-related varieties are a low-cost insurance policy against salinity inundation in high risk areas. Combined, these results highlight the need to address complex factors beyond current economic profits, like environment, community choices, and risk mitigation, when designing technologies and policies that support farmer adaptation to climatic change.

Enhancing livestock vaccination decision-making through rapid diagnostic testing

•Compared to vaccination, the collective approach to diagnostic testing presents a low-fixed cost.•Existing household livestock-health behaviors increase the likelihood for uptake of preventative health practices.•Initial evidence to support household investments in livestock preventative health over therapeutic treatments.

Communities’ Livelihood Vulnerability to Climate Variability in Ethiopia

Ethiopia has experienced more than 10 major drought episodes since the 1970s. Evidence has shown that climate change exacerbates the situation and presents a daunting challenge to predominantly rain-fed agricultural livelihoods. The aim of this study was to analyze the extent and sources of smallholder famers’ livelihood vulnerability to climate change/variability in the Upper Blue Nile basin. We conducted a household survey (n = 391) across three distinct agroecological communities and a formative composite index of livelihood vulnerability (LVI) was constructed. The Mann–Kendall test and the standard precipitation index (SPI) were employed to analyze trends of rainfall, temperature, and drought prevalence for the period from 1982 to 2016. The communities across watersheds showed a relative difference in the overall livelihood vulnerability index. Aba Gerima (midland) was found to be more vulnerable, with a score of 0.37, while Guder (highland) had a relatively lower LVI with a 0.34 index score. Given similar exposure to climate variability and drought episodes, communities’ livelihood vulnerability was mainly attributed to their low adaptive capacity and higher sensitivity indicators. Adaptive capacity was largely constrained by a lack of participation in community-based organizations and a lack of income diversification. This study will have practical implications for policy development in heterogeneous agroecological regions for sustainable livelihood development and climate change adaptation programs.