Projections of maize yield vulnerability to droughts and adaptation options in Uganda

Sub-Saharan Africa is likely going to experience more intense and frequent droughts with high parallel possibilities of ramifications on maize yields. While there is a lot of scholarship dwelling on the ramifications of droughts on maize yields at the level of Africa, little has been researched at lower scales. This study presents past (1960–2014) vulnerability of maize yields to droughts based on a previous study (Epule et al., 2017) and projects the future vulnerability of maize yields to droughts by calculating the sensitivity, exposure and adaptive capacity of maize yields to droughts for the period 2015–2050. The results show that maize yields are more vulnerable in the north of Uganda for the period 1960–2014. However, adaptive capacity is higher in the south. Maize yields also record higher levels of sensitivity and exposure in the north with the latter patterns explained by variations in precipitation, temperature, rich volcanic soils, access to rivers and lakes. In terms of future vulnerability for the period 2015–2050, this study shows that the level of vulnerability of maize yields to droughts in Uganda will increase to levels higher than what currently obtains. For example, the vulnerability index will increase from 0.54 under the 1.5 °C to 0.70 under the 2.0 °C and to 1.54 under the 2.5 °C scenario. Sensitivity is also likely to increase while exposure and adaptive capacity are most likely to remain the same. Overall, it can be said that the future of maize production in Uganda under present and future circumstances remains very bleak without concrete actions. As a way forward, land use policy designers will have to integrate water management, agroforestry, climatic information diffusion, training and indigenous knowledge into land use planning decisions in the context of agriculture.     

Evaluating irrigation investments in Malawi: economy‐wide impacts under uncertainty and labor constraints

Irrigation expansion is critical to increase crop yields and mitigate effects from climate change in Sub‐Saharan Africa, but the low profitability has led to little irrigation investments in the region so far. Using an integrated modeling framework, we simultaneously evaluate the returns to irrigation arising from both economic and biophysical impact channels to understand what determines the profitability of irrigation in Malawi. Our results confirm that the returns to irrigation cannot cover the costs in Malawi. While labor‐intensive irrigation expansion leads to unfavorable structural change in the short‐run, the profitability hinges on low irrigated yields that fall far from expectations due to insufficient input use and crop management techniques. On the other hand, we find that the nonmonetary benefits of irrigation regarding higher food security, lower poverty, and reduced vulnerability to climate change make investments in irrigation worthwhile to improve the livelihoods of smallholders.     

Harnessing sustainability,resilience and productivity through conservation agriculture: the case of likoti in Lesotho

Subsistence farmers in Lesotho have been able to boost agricultural yields and increase food production by adopting conservation agriculture. The practice, locally known as likoti, also contributes to combating soil erosion and to enhancing fertility. The socio-economic and environmental benefits help poor households to rehabilitate and strengthen their livelihood capital base and ultimately help rural communities to build system resilience in the face of widespread poverty and increasing vulnerability that affect the country. This paper discusses the major advantages associated with the spread of likoti. By drawing on primary data collected by FAO-Lesotho, it enquires into the determinants of adoption, thereby highlighting constraints and options for future up-scaling. The results show that attending appropriate training is a crucial prerequisite for the correct adoption of likoti. However, training is more effective when trainers pursue true participation and when social capital among farmers is stronger. Further important determinants of adoption are the level of education and the economic incentives provided to vulnerable households. Stronger policy and institutional support in all these areas would thus help address the cultural and resource constraints that limit the full potential of likoti to be harnessed and ultimately hinder its further spread throughout the country.     

Gendered impacts of fertilizer subsidy removal programs in Malawi and Cameroon

Gladwin's^** main contention is that women provide most of the agricultural labor in sub-Saharan Africa and because much of this labor is oriented to food production for home consumption, the effects of structural adjustment programs on them and the children they work to feed are likely to be different than on men who produce crops for commercial and export production. Her specific hypothesis for Malawi is that the removal of the fertilizer subsidy affects women farmers more than men farmers because it reduces fertilizer use on local maize. As part of the structural adjustment program, a major purpose of removing the fertilizer subsidy is to reallocate resources from food production for domestic consumption to cash crop production for export. In Gladwin's analysis, men farmers produce hybrid maize and tobacco for export and women produce the subsistence food crop, local maize. Gladwin's main contention is probably correct. For the Malawi case, the presentation does not support the hypothesis because two of the major underlying assumptions are inappropriate and the evidence provided is inconclusive. This comment proceeds by discussing the two assumptions and corresponding evidence. The purpose of this comment is not to contradict the hypothesis, but to clarify the Malawi situation and to suggest that a different analytical approach is needed in that context.     

Is native timber tree intercropping an economically feasible alternative for smallholder farmers in the Philippines?

Integration of trees on upland farms in the Philippines has been slower than expected and desirable from an environmental perspective. Our economic and risk analysis points to current policies as part of the problem. The study compares three domesticated indigenous timber trees (Shorea contorta V., Pterocarpus indicus J., and Vitex parviflora W.) intercropped with maize against a benchmark of the widely used exotic mahogany (Swietenia macrophylla K.). We used a biophysical simulation model (WaNuLCAS 3.1) to represent interaction between trees and crops for a fundamental level of water, nutrient and light capture as the basis for production functions. External conditions affecting systems profitability were accounted for in the Policy Analysis Matrix (PAM). Elements of risk were introduced through Monte Carlo simulation. Study results revealed that from a farmer’s perspective intercropping systems provide similar (within an uncertainty range of + or ? 10%) returns to monocropping scenarios. When net subsidies and taxes are accounted for, social profitability evaluations favour tree intercropping at high tree densities. The net effect of the current bias in price policies towards food production therefore refrains farmers from making decisions to integrate trees on farms; a decision that is actually in the national interest on economic grounds, even without consideration of positive environmental effects.     

Maize-legume intercropping in central Malawi: determinants of practice

In Malawi, population growth has reduced opportunities for farmers to expand and cultivate new land. The country's primary farming population is comprised of smallholders, many who cultivate monocultures of maize (Zea mays). To reduce negative outcomes from this practice, intercropping maize with legumes has been promoted. The sustainable intensification (SI) practice was once widely used, but has declined in recent decades. Little is known about the determinants of intercropping or its role in agricultural development. The objective of this study was to examine the drivers of intercropping among smallholders. We used multiple logistic regression analysis to estimate the determinants of intercropping based on a survey of 324 households. Smallholders who sold legumes were more likely to intercrop, contrary to literature positing intercropping as a practice primarily intended to enhance food security. In addition, complementary SI practices such as fertilizer, manure and compost application were more likely to have occurred on intercropped fields relative to sole maize fields. Furthermore, smallholder farmers appeared to apply more fertilizer to their intercropped fields relative to their sole maize fields. The study highlights the value of including field-level characteristics and household socioeconomic survey data to understand farming practices as a means to inform agricultural policy.

Abbreviations: SI: sustainable intensification; MLI: maize-legume intercrop; DL: doubled-up legumes     

Welfare impacts of maize–pigeonpea intensification in Tanzania

This article examines the driving forces behind farmers’ decisions to adopt improved pigeonpea and maize and estimates the causal impact of technology adoption on household welfare using data obtained from a random cross‐section sample of 613 small‐scale farmers in Tanzania. We use seemingly unrelated and recursive bivariate probit regressions to test the endogeneity and joint decision making of pigeonpea–maize production. A double hurdle model is used to analyze the determinants of the intensity of technology adoption conditional on overcoming seed access constraints. To address the impact of adoption on welfare, the article employs both propensity score matching and switching regression techniques. Results from bivariate probit models show that unobservable factors cause both decisions to be correlated but the finding does not support the conjecture that both decisions are made jointly. Overall the analysis of the determinants of adoption identifies inadequate local supply of seed, access to information, human capital, and access to private productive asset as key constraints for pigeonpea technology adoption. The causal impact estimation from both the propensity score matching and switching regression suggests that maize/pigeonpea adoption has a positive and significant impact on income and consumption expenditure among sample households.     

Adoption and Impacts of Sustainable Agricultural Practices on Maize Yields and Incomes: Evidence from Rural Zambia

This paper uses a multinomial endogenous treatment effects model and data from a sample of over 800 households and 3,000 plots to assess the determinants and impacts of adoption of sustainable agricultural practices (SAPs) on maize yields and household incomes in rural Zambia. Results show that adoption decisions are driven by household and plot level characteristics and that the adoption of a combination of SAPs raises both maize yields and incomes of smallholder farmers. Adoption of improved maize alone has greater impacts on maize yields, but given the high cost of inorganic fertiliser that limits the profitability of adoption of improved maize, greater household incomes are associated rather with a package involving SAPs such as maize–legume rotation and residue retention.     

Research,development and scaling-up the adoption of fodder shrub innovations in East Africa

Smallholder farmers in developing countries face numerous limitations that hinder them from embracing improved agricultural practices and innovations with great potential for meaningful transformations of livelihoods. Consequently, farmers continue living in vicious cycles of poverty despite decades of government and donor expenditures on poverty alleviation. In the last two decades, research and development organizations collaborated in testing and validating selected fodder shrub species as reliable sources of less expensive and easily available protein feeds. With minimal interventions, the research findings have great potential to improve productivity for many smallholder farmers. Tested species include Calliandra calothyrsus, Leucaena spp., Chamaecytisus palmensis, Sesbania sesban, Morus alba and Gliricidia sepium. Dissemination and adoption surveys estimated that 205,000 smallholder farmers (40–50 per cent being women) had planted fodder shrubs by 2005. Currently, fodder shrubs contribute US$3.8 million annually to farmers' incomes and estimated potential annual income is US$81 million. Factors associated with success in fodder scaling-up include deliberate involvement of fodder technology champions, collective action in community mobilization and project implementation, pluralistic extension approaches, sustainable germplasm supply systems, broader partnerships and civil society campaigns. Constraints and challenges include: ineffective delivery of extension and research services, inhibitive policies, political interferences, frequent droughts and inadequate monitoring and evaluation systems.     

The Costs of Coexistence Measures for Genetically Modified Maize in Germany

We estimate the perceived costs of legal requirements (‘coexistence measures’) for growing genetically modified (GM) Bt maize in Germany using a choice experiment. The costs of the evaluated ex‐ante and ex‐post coexistence measures range from zero to more than €300 per measure and most are greater than the extra revenue the farmers in our survey expect from growing Bt maize or than estimates in the literature. The cost estimates for temporal separation, the highest in our evaluation, imply that the exclusion of this measure in Germany is justified. The costliest measures of the ones that are currently applied in Germany are joint and strict liability for all damages. Our results further show that neighbours do not cause a problem and opportunities for reducing costs through agreements with them exist. Finally, we find that farmers’ attitudes towards GM crops affect the probability of adoption of Bt maize. Our results imply that strict liability will deter the cultivation of Bt maize in Germany unless liability issues can be addressed through other means, for example, through neighbours agreements.     

Targeting,bias, and expected impact of complex innovations on developing‐country agriculture: evidence from Malawi

Agronomic analyses of new technologies are often conducted under carefully controlled research station programs or trials managed by self‐selected farmers. Oftentimes, the technologies are then scaled up with minimal evaluation under real‐world conditions. Yet, the interim step between agronomic trials and large‐scale promotion is crucial to generate evidence on the social and economic impact of technologies that is both internally valid and generalizable. The article focuses on a participatory action research program in Malawi designed to test and identify scalable technology options to intensify the smallholder sector and contribute to poverty reduction and food and nutrition security. We examine the socioeconomic characteristics of farmers testing technologies and find evidence of systematic targeting of better‐endowed farmers. After controlling for observable differences using matching and a doubly robust estimator, we find evidence of early positive effects on maize yield and harvest value, although placebo tests suggest possible selection on unobservables. We note that attention should be given to program design and household characterization to better define and improve targeting criteria, technology selection, and external validity.     

Faidherbia albida on the Tonga Plateau of southern Zambia: an agroecological analysis

Faidherbia albida is a tree species indigenous to semi-arid regions of Africa that reportedly substantially increases maize (Zea mays) yields in its immediate vicinity. In southern Zambia, F. albida is widely used in indigenous maize farming systems and this has apparently increased over the past two decades. Using a combination of interviews, group meetings, and observations, this study sought to understand why this species seems to have recently been embraced, while other technological innovations apparently have not. We observed a bimodal age distribution of the trees in agricultural fields and posit that the missing cohorts were removed as weeds as a result of evolving notions of what constituted modern farming practices in the emerging maize economy. With subsequent research and social promotion of the beneficial effects of F. albida, farmers now allow the trees to grow in their fields. A holonic analysis points to the important relationship of F. albida to contexts that shaped past and current uses of the tree by farmers on the Tonga Plateau: information, maize, cattle, land tenure, and government policy. Advice promulgated by social promotion activities took root in farmer knowledge contexts because of positive regard for F. albida and timeless injunctions against cutting mature specimens. Furthermore, cultivation of the tree was highly compatible with other important contexts in which farmers operate. However, our research also revealed the potential for adoption of the tree to create new tensions arising from the strong gendering of work and crops in the region.     

Participatory trials and farmers' social realities: understanding the adoption of legume technologies in a Malawian farmer community

This article presents results from a study exploring the reasons for low adoption of legume technologies to improve soil fertility by farmers from a community in central Malawi who took part in participatory trials. This study explores the influence of gender roles in agriculture and land ownership and socio-economic differentiation in the community. Because most women do not own land and are traditionally responsible for legume crops, they have little interest in managing soil fertility for maize crops. Men are not interested in using legumes in maize-cropping systems. Some are too poor: this group needs to complement their subsistence maize production with paid labour on the farms of better-off farmers; restricting the labour availability for their own farming activities. Wealthier farmers have access to, and prefer to use chemical fertilizer and cattle manure. Take-up rates among the middle group of farmers were also low. This study discusses how these (and other) factors influence the (non-)adoption of maize-legume technologies in Malawi and the effectiveness of participatory research. It emphasizes how differentiated farmer-realities affect the uptake of technologies identified as promising in participatory field evaluations.     

On-Farm Nutrient Balance Studies in the Dry Zone of Myanmar

On-farm experiments to study soil fertility depletion—one of the biophysical factors limiting crop production—were conducted in six villages of central Myanmar during 1997 to 1999. Systematic socioeconomic surveys and analysis of socioeconomic and crop production factors aided the selection of farmers.

Topsoil mineral nitrogen content at the start of the cropping season was high (10–25 mg N kg^?1). Available phosphorous was around the threshold level for most crops, but exchangeable potassium was low. The predominant continuous cropping system of sole groundnut was on average positive for P (0.24 kg ha^?1 y^?1) and K (7.05 kg ha^?1 y^?1) and negative for N (?32.4 kg ha^?1 y^?1). A negative balance for N in the groundnut/pigeonpea (?58 kg ha^?1 y^?1) and mung bean/pigeonpea (?56 kg ha^?1 y^?1) intercropping systems was noted. The nutrient balances were positive in early sesame—late sesame (29 kg N ha^?1 y^?1, 8 kg P ha^?1 y^?1, 33 kg K ha^?1 y^?1) and early sesame/pigeonpea (8 kg N ha^?1 y^?1, 15 kg P h^?1 y^?1, 44 kg K ha^?1 y^?1) production systems while sole sorghum system resulted in positive balance for N (23.8 kg ha^?1 y^?1) and negative balance for K (?3.8 kg ha^?1 y^?1).     

Payments for environmental services to promote “climate‐smart agriculture”? Potential and challenges

Payments for environmental services (PES) have gained wide popularity as approaches to promote environmentally friendly land use or agricultural production practices. Yet academics have also voiced concerns against seeing PES as a panacea. This article discusses whether PES is an appropriate and promising approach to promote so‐called “climate‐smart agriculture” (CSA) practices, which we define as agricultural production practices that contribute to CO₂ emission reductions and/or removals and provide benefits to farmers via increased productivity and profits and reduced vulnerability to climate change. PES appears most promising for the promotion of CSA practices in small‐scale farming contexts with low incomes. Effective design, however, requires solid estimates of cost and benefit flows from CSA adoption over time, accounting for differences in socioeconomic and ecological conditions, and addressing the risk of leakage. Funding for such PES will likely have to come from public sources, and seems most promising where synergies with other objectives such as agricultural development, food security, and climate adaptation or other environmental services exist. The potential of alternative approaches for CSA support such as taxation with rebates for CSA practices, CSA‐related investment support such as microcredits, and hybrid approaches such as conditional microcredit should be further investigated.     

Climate risk,vulnerability and resilience: Supporting livelihood of smallholders in semiarid India

Using panel data from 256 smallholder households from 2006 to 2014 in three semiarid regions India, this study develops a framework for quantifying vulnerability and resilience by accounting for a smallholder household’s ability to adapt and respond to climatic risk. Findings indicate that although smallholders with smaller landholdings are more vulnerable to climatic risk (drought, in our case), they are also more resilient than their counterparts. Results reveal that cropping intensity and crop risk increase the vulnerability of smallholders to climatic risk, but large farms are less vulnerable. Diversification in on-farm enterprises, like livestock units, and off-farm income sources, play significant roles in increasing smallholder households’ resilience to climatic risk. Other drivers of resiliency include the choice of cash and risky crops, borrowing capacity, liquid investments, and the ability to regain yields.     

Measuring postharvest losses at the farm level in Malawi

This article measures farm‐level postharvest losses for maize, soya and groundnuts among 1,200 households in Malawi. Farmers answered a detailed questionnaire designed to learn about losses during harvest and transport, processing and storage and which measures both complete losses and crop damage. The findings indicate that fewer than half of households report suffering losses conditional on growing each crop. Conditional on losses occurring, the loss averages between 5 and 12 per cent of the farmer's total harvest. Compared to nationally representative data that measure losses using a single survey question, this study documents a far greater percentage of farmers experiencing losses. We find that losses are concentrated in harvest and processing activities for groundnuts and maize; for soya, they are highest during processing. Existing interventions have primarily targeted storage activities; however, these results suggest that targeting other activities may be worthwhile.     

Integration of conservation agriculture in smallholder farming systems of southern Africa: identification of key entry points

A component-omission experiment based on the principle of conservation agriculture (CA) was established on smallholder farms for three seasons in Murehwa and Hwedza districts, Zimbabwe; Barue district in Mozambique; Balaka district and Chitedze Research Station in Malawi, and Monze district in Zambia to identify strategies for improving crop productivity and livelihoods for smallholder farmers. The objective of the experiment was to evaluate the effect of tillage, residue retention, fertiliser application and weed control on maize yield. In addition, the study analysed possible combinations of these factors that could provide a sustainable entry point for intensification through CA. Results showed that fertilisation had the strongest effect on crop yield in both tillage systems; adequate fertilisation is therefore key to success in CA. Retention of crop harvest residues increased yield in no-tillage systems; no-tillage without residues depressed yield by 50% when compared with yields of conventional tillage. A step-wise integration of CA into the smallholder farming systems is proposed as a possible strategy to avoid new constraints on smallholder farms. If resources are limiting, farmers may apply all principles on small areas to overcome the initial demand in resources (labour, fertiliser and residues), and once productivity is raised, they can expand.     

草原生态补偿机制下 天祝县农牧民生计脆弱性评估

本文以可持续生计框架中的生计资本为研究侧重点,在草原生态补偿机制实施的政策背景下,通过对天祝县农牧民调查获得数据,量化分析农牧民生计资本及其脆弱性类型和程度.研究表明,分析单一农牧民家庭生计脆弱性,可划分农牧民生计脆弱性类型为单一生计资本匮乏型和多元生计资本匮乏型;综合分析农牧民家庭生计脆弱性发现生计资本总体仍较为脆弱...     

Farm machinery use,off‐farm employment and farm performance in China

We analyse the joint impacts of farm machinery use and off‐farm employment on maize yields and agrochemical expenses from a household survey of 493 farmers in China. Our findings are obtained from an innovative two‐stage econometric procedure that combines a bivariate ordered probit model with an endogeneity‐corrected ordinary least square regression model. The results show that farmers are jointly making decisions to use farm machines and to work off the farm and that these two household activities affect maize yields and agrochemical expenses in different ways. We show that farm machinery use significantly increases both maize yields and agrochemical expenses, while off‐farm employment significantly decreases agrochemical expenses. Our findings highlight the importance of additional machinery use in increasing farm production; the need to account for possible endogeneity in estimation; and the statistical significance of key household characteristics (gender, education, and household size) on overall farm production.