Types of Research
This brief reviews the literature and empirical evidence on waste extraction and treatment in the developing world. The brief assesses the quantity and quality of research supporting key components of program theory related to the extraction of sludge from on-site sanitation facilities and pre-disposal transport. In general, we find few empirical studies that directly evaluate the assertions of the program theory. Most of the evidence in the literature that addresses the target components of program theory is based upon case studies or general observational and experiential assertions by sanitation experts. Where appropriate, we have identified evidence in the literature according to whether case studies or informal observations formed the basis of the conclusion.
The purpose of this literature review is to provide qualitative and quantitative examples of technologies, constraints and incentives for efficient waste treatment and reuse in Sub-Saharan Africa and Southeast Asia. We present relevant case studies and expert observations and experiences on the nutrient content in urine and feces, contaminants frequently found in untreated sludge and wastewater, waste treatment technologies that may be relevant for low-income countries, risks associated with waste reuse, benefits to resource recovery in agriculture. We further discuss reasons for waste treatment failures, including urbanization, observations on challenges with market-driven reuse in less developed countries, and examples of net-positive energy facilities in Europe and the United States. Much of the evidence presented in the literature relates to wastewater treatment processes or the sludge produced from wastewater treatment as opposed to untreated fecal sludge. However, examples of risks, failures, and opportunities for raw sludge treatment and reuse are discussed when available. In some cases, empirical evidence or case studies were not available for developing countries and alternatives are presented. Overall we found the empirical evidence on waste treatment and reuse in developing countries is quite thin.
The purpose of this literature review is to identify the linkages between increases in agricultural productivity and poverty reduction. The relevant literature includes economic theory and evidence from applied growth and multiplier models as well as micro-level studies evaluating the impact of specific productivity increases on local poverty outcomes. We find that cross-country and micro-level empirical studies provide general support for the theories of a positive relationship between growth in agricultural productivity and poverty alleviation, regardless of the measures of productivity and poverty that are used. The evidence also suggests multiple pathways through which increases in agricultural productivity can reduce poverty, including real income changes, employment generation, rural non-farm multiplier effects, and food prices effects. However, we find that barriers to technology adoption, initial asset endowments, and constraints to market access may all inhibit the ability of the poorest to participate in the gains from agricultural productivity growth.
Bt maize technology involves developing hybrid maize crops that incorporate genes from the soil-dwelling bacteria Bacillus thuringiensis (Bt). The primary benefit of Bt maize technology is the heightened crop protection from stem borers, which are maize pests that can inflict serious crop losses. Bt maize has been cultivated in Mexico, South Africa and several countries in the European Union, with limited cultivation in Sub-Saharan Africa (SSA). This report provides a summary of literature on the potential benefits and challenges associated with Bt maize production in SSA. Research studies of Bt maize in the Philippines and South Africa are also briefly reviewed. There is little peer-reviewed literature available, with evidence challenging the assumed benefits of Bt maize for smallholder farmers in SSA. As a result, we also review research briefs and conference proceedings available from reputable international organizations. Although some of the available literature references the ethical concerns over Bt maize production, we focus on searching for science-based discussions related to any potential biodiversity, biosafety, or socio-economic impacts of Bt maize technology for smallholder farmers in SSA.
Yam is a major staple in West and Central Africa and an important supplementary food in East Africa. In Sub-Saharan Africa (SSA), virtually all yams are produced for human consumption, with women responsible for processing yams for consumption. This brief provides an overview of the role of women in yam production, and provides a framework for analyzing barriers to women and technology’s impact on women throughout the cropping cycle. We find that though yam was traditionally considered a man’s crop, it is clear that women farmers contribute greatly to yam cultivation, especially during weeding, harvesting, and processing. Propagation of improved varieties with resistance to pests and diseases like yam mosaic disease has great potential to benefit women farmers. Increased yields and lower post-harvest losses will increase household food security. However, because yams extract high amounts of nutrients from the soil, soil and land management techniques are necessary to ensure future gains in yield. Women’s groups serve as potential venues for dissemination of new yam cultivation and processing technologies. Additionally, women’s groups can undertake new propagation techniques as income generating activities. Women farmers need increased extension efforts to fully benefit from technology improvements.
Though not indigenous to Sub-Saharan Africa (SSA), cassava plays, to varying degrees, five major roles in African development: famine-reserve crop, rural food staple, cash crop for urban consumption, livestock feed, and industrial raw material. Cassava production in SSA was historically a significant staple crop for smallholder farmers and continues to be the second most important food crop in Africa (after maize) in terms of calories consumed. Subsistence crops such as cassava are often considered women’s crops with the standard explanation that women are responsible for feeding the family and thus prefer to grow crops for the household. This brief reviews the role that women play in cassava production, and considers ways to better address gender issues from planting through post-harvest production. We find that the potential gains to cassava production made possible through improved technology will not be fully realized without the participation of women farmers and without women farmers having access to credit, markets, and extension services. Additionally, evidence from SSA suggests that labor for harvesting and processing, rather than labor for weeding, has become the key labor constraint for cassava, and addressing this concern may be more important than further yield increases for raising production levels.
The millets, a group of small-seeded grasses indigenous to Africa, are an extremely important staple food in resource-poor regions of Sub-Saharan Africa (SSA). Millet requires few inputs, suffers less from insect pests and disease than other grains, and can tolerate areas even too hot and dry for sorghum. These characteristics make millet an essential component of food security and risk management strategies for many Africans, though both consumption and production per capita of millet has declined in the last 20 years as farmers have shifted toward maize and rice production. This brief provides an overview of the role of women in millet production, and provides a framework for analyzing barriers to women and technology’s impact on women throughout the cropping cycle. We find that the shift away from millet may result in poorer nutrition and increased time burden for women where they must find alternatives to millet fuel, but that little is known about these consequences. Investing in improved varieties that account for both men’s and women’s preferences, introducing labor-saving technology, and increasing market access all have the potential to increase millet’s production and consumption on the continent.
Sorghum grows well in arid and semi-arid agroecological zones and is thus one of the most important cereals in the Sahel region of Sub-Saharan Africa (SSA). Both men and women cultivate sorghum primarily for household consumption, though women are nearly exclusively responsible for post-harvest production of the grain, including brewing and selling sorghum beer. This brief provides an overview of the role of women in sorghum production, and provides a framework for analyzing barriers to women and technology’s impact on women throughout the cropping cycle. We find that improved sorghum varieties have the potential to greatly increase sorghum yields in SSA by alleviating cultivation threats from striga, pests, and drought. Because women farmers are the primary cultivators of sorghum, they stand to benefit most from these improved varieties. However, low adoption rates of new technologies suggest that more resources need to be dedicated to extension efforts and informal seed distribution networks that include women farmers. Post-harvest processing of sorghum is both time and labor intensive and is causing many women farmers to transition to maize or rice. Finally, increased demand for sorghum as a biofuel stock may not translate into gains for women farmers as expected, because women farmers tend to lack input resources, and women farmers often lose control over crops as they transition to cash crops.
In Sub-Saharan Africa (SSA), maize alone provides an estimated one third of the mean caloric intake and in 2006, accounted for 21% of all harvested food crops, making it the single most important food crop in the region. In addition, maize is also used as feedgrain and fodder, adding to its importance in integrated smallholder farming systems in SSA. In general, women are the main producers of staple crops such as maize. Understanding the gender dimensions of maize is particularly challenging because maize is used as both a subsistence and cash crop, and may be considered either a male or female crop depending on farmer circumstances and how the particular variety is promoted. This brief provides an overview of the role of women in maize production, and provides a framework for analyzing barriers to women and technology’s impact on women throughout the cropping cycle. We find that lower access to factors such as extension access, education level, land, and labor contribute to female’s lower rate of maize technology adoption. Understanding women’s disproportionate access to resources and how improved technology may change allocation of resources should help project developers improve both women’s and men’s productivity.
In the last half century, the increased opportunity cost of women’s time in Sub-Saharan Africa (SSA) has led to remarkable growth in the consumption of wheat and other easy-to-prepare staples. Wheat tends to be grown and processed on a large scale in SSA. Ethiopia (SSA’s largest producer of wheat) is the exception, where smallholders are responsible for 76% of total production. This brief provides an overview of the role of women in wheat production, and provides a framework for analyzing technology’s impact on women throughout the cropping cycle. We find that many constraints exist to adoption of improved wheat varieties by women. A review of improved wheat variety adoption in the developing world found that it takes 5-10 years after breeding to the release and another 5-10 years for full adoption, but this length of time has been found to be reduced with the use of participatory breeding, varietal selection, and gender analysis. By including women in every stage of development and planning of new technologies, programs can become more aware of the needs of targeted women and therefore, increase adoption rates and improve the productivity of men and women in wheat farming.