Evans School Policy Analysis & Research Group (EPAR)

There is a wide gap between realized and potential yields for many crops in Sub-Saharan Africa (SSA). Experts identify poor soil quality as a primary constraint to increased agricultural productivity. Therefore, increasing agricultural productivity by improving soil quality is seen as a viable strategy to enhance food security. Yet adoption rates of programs focused on improving soil quality have generally been lower than expected. We explore a seldom considered factor that may limit farmers’ demand for improved soil quality, namely, whether farmers’ self-assessments of their soil quality match soil scientists’ assessments. In this paper, using Tanzania National Panel Survey (TZNPS) data, part of the Living Standards Measurement Study – Integrated Surveys on Agriculture (LSMS-ISA), we compare farmers’ own assessments of soil quality with scientific measurements of soil quality from the Harmonized World Soil Database (HWSD). We find a considerable “mismatch” and most notably, that 11.5 percent of survey households that reported having “good” soil quality are measured by scientific standards to have severely constrained nutrient availability. Mismatches between scientific measurements and farmer assessments of soil quality may highlight a potential barrier for programs seeking to encourage farmers to adopt soil quality improvement activities. 

Water is a critical input for significantly enhancing smallholder farmer productivity in Sub-Saharan Africa (SSA) where less than 5% of farm land is irrigated, and in India where 42% of farm land is irrigated.  For many years, donors have invested in human-powered treadle pump technologies as a point of entry for smallholder farmers unable to afford motorized pumps. In spite of some successes in treadle pump promotion, however, there is a widespread perception that as soon as smallholder farmers can afford to they quickly transition to motorized diesel- powered pumps. While diesel pumps substantially ease farmers’ workload, they pollute excessively (both in terms of local air quality and greenhouse gas emissions), pump excessive amounts of water, and put farmers at the mercy of cyclical spikes in fuel prices. This brief provides an overview of state-of-the-art alternative energy pumps, including technologies available and implementation lessons learned from China, India, Africa, South America and other regions. Through a literature review, written surveys and phone interviews with water pump producers and non-governmental organizations (NGOs) we evaluate the availability, affordability, and adoption rates of alternative energy technologies in developing countries. Our findings suggest that no single alternative energy water pumping system is a “silver bullet” for rural smallholder irrigation needs. Biofuels may prove a successful short- to intermediate-term solution for farmers who already have access to diesel pumps, but other problems associated with diesel engines, including high maintenance costs and excessive water use remain even when biofuels are used. Solar systems eliminate pollution almost entirely, reduce water consumption, and eliminate the need to purchase fuels. However solar systems are typically prohibitively expensive for smallholder farmers. Wind powered pumping solutions have not proven successful to date, with high costs and irregular wind patterns (either too little or too much wind) proving substantial barriers to widespread adoption.

Without availability and access to a variety of foods, populations in the developing world are suffering from deficiencies in iron, zinc, iodine, vitamin A, and other micronutrients in addition to deficiencies in energy and protein. Supplementation and fortification programs have demonstrated effectiveness, but there is an increasing interest in potentially more sustainable solutions via agricultural interventions. The review examines the literature regarding agricultural interventions and pathways to diet diversification and whether desired nutritional outcomes are achieved.  We find a strong sentiment that agricultural interventions can improve dietary diversity, and that dietary diversity can improve nutrition and related health outcomes. The programs with demonstrated ability to improve nutrition outcomes are most often cross-cutting interventions, borrowing from the agriculture, nutrition, and public health traditions. While these multi-platform programs can be costly to evaluate and difficult to implement, the evidence supports their potential to create sustainable quality-of-life improvements in target regions. The pathways by which agricultural interventions achieve impact are not fully clear, however. The greatest knowledge gaps are directly related to the lack of integration between program design and evaluation. Many evaluations are based on small sample sizes, lack control groups or baseline data, are subject to selection bias, or face other challenges to rigorous statistical analysis. 

Market-oriented agricultural production can be a mechanism to increase smallholder farmer welfare, rural market performance, and contribute to overall economic growth. Cash crop production can allow households to increase their income by producing output with higher returns to land and labor and using the income generated from sales to purchase goods for consumption. However, in the face of missing and underperforming markets, African smallholder households are often unable to produce efficiently or obtain staple foods reliably and cheaply. This literature review summarizes the available literature on the impact of smallholder participation in cash crop and export markets on household welfare and rural markets. The review focuses exclusively on evidence from Sub-Saharan Africa regarding top and emerging export crops, with the addition of tobacco and horticulture due to the volume of research relevant to smallholder welfare gains from the production of these crops. It includes theoretical frameworks, case studies, empirical evidence, and historical analysis from 42 primary empirical studies and 112 resources overall.