Research Topics

EPAR Research Brief #158
Publication Date: 08/03/2011
Type: Literature Review
Abstract

This literature review examines the environmental impacts of water buffalo in pastoral and mixed farming systems in Sub-Saharan Africa, South Asia, and South America). The environmental impacts of water buffalo are less widely studied than those of the other livestock species included in this series; typically, the environmental impacts of water buffalo are incorporated into discussions of cattle without more detailed impacts being broken down by bovine type. In Asia and India, where the majority of buffalo are raised, buffalo are typically kept in small herds of only a few animals, which may minimize the local impacts of their grazing on vegetation, soil erosion and water pollution. Some aspects of buffalo feeding and life cycle patterns, as observed in the Amazon, may cause their greenhouse gas emissions to differ from those of cattle: buffalo can fatten on a wider range of grasses, reach market size in a shorter time, transition better from dry to wet seasons, and are more resistant to bovine diseases. While buffalo grazing and trampling can lead to land degradation, buffalo can contribute to nutrient and resource cycling in farming systems because their manure is considered good fertilizer and they can remove and utilize biomass grown on agricultural plots. Mitigation strategies vary by category of environmental impact, but largely suggest improved productivity to reduce land conversion, modified management systems (e.g., biodiversity, water use and consumption, farm and pastures, and waste), and the reduction of livestock numbers altogether.

EPAR Research Brief #155
Publication Date: 07/31/2011
Type: Literature Review
Abstract

This literature review examines the environmental impacts of cattle in pastoral and mixed farming systems in Sub-Saharan Africa and South Asia. Cattle are frequently cited as having the most severe overall environmental impacts among livestock species due to: methane and nitrous oxide released from digestion and manure; land use and conversion; desertification; inefficient ratio of weight of feed and water consumed to weight of meat and dairy produced; conflicts between livestock herders and wildlife; the large volume of wastewater produced in meat and hide processing; and overgrazing of riparian areas. However, cattle have also been found to provide several environmental benefits such as keeping wildlife corridors open, preventing the spread of noxious weeds, and promoting the growth of local vegetative species. Mitigation strategies vary by category of environmental impact, but largely suggest improved productivity to reduce land conversion, modified management systems (e.g., biodiversity, water use and consumption, farm and pastures, grain and other feed, and waste), and the reduction of livestock numbers altogether. 

EPAR Research Brief #156
Publication Date: 07/31/2011
Type: Literature Review
Abstract

This literature review examines the environmental impacts of goats in pastoral and mixed farming systems in Sub-Saharan Africa and South Asia. We find that the most notable environmental implications of goats stem from their ability to graze on a wide variety of biomass sources in frequently marginal environments; while this intensive grazing stimulates biodiversity loss and may be more severe than grazing by other livestock species, goats are not a major driver of forest clearing due to their low economic value. Environmental benefits of goat production include keeping wildlife corridors open, preventing the spread of noxious weeds, and promoting the growth of local vegetative species through moderate grazing. Goats are also more water-efficient than large ruminants such as cattle. Mitigation strategies vary by category of environmental impact, but largely suggest improved productivity to reduce land conversion, modified management systems (e.g., biodiversity, water use and consumption, grazing intensity and frequency, and waste), and the reduction of livestock numbers altogether.

EPAR Research Brief #157
Publication Date: 07/31/2011
Type: Literature Review
Abstract

This literature review examines the environmental impacts of chickens in pastoral and mixed farming systems in Sub-Saharan Africa and South Asia. Compared to ruminant species (cattle, water buffalo, and goats), chickens produce lower carbon dioxide, methane, and nitrous oxide emissions, are a less significant driver of human expansion into natural habitat or of overgrazing, have lower impacts on the water cycle, and cause less destruction of natural habitats. Poultry’s major impacts on land degradation result from the production of their grain-intensive feed. Chicken production also poses a threat to avian biodiversity, as chickens are susceptible to viruses and act as vectors of disease transmission to avian wildlife. Chicken manure is widely viewed as a valuable fertilizer in developing countries, although transportation costs limit manure sales in local markets and the high nitrogen-phosphorous ratio can impact certain soils and water. Mitigation strategies vary by category of environmental impact, but largely suggest modified management systems (e.g., biodiversity, health, livestock feed efficiency, and waste).

EPAR Technical Report #118
Publication Date: 03/16/2011
Type: Literature Review
Abstract

This report combines analyses from four previous EPAR briefs on the effects of climate change on maize, rice, wheat, sorghum, and millet production in Sub-Saharan Africa (SSA). In addition, this brief presents new analysis of the projected impact of climate changes in SSA. We include comparisons of the importance of each crop, of their vulnerability to climate change, and of the research and policy resources dedicated to each. Especially with respect to climatic susceptibility, these rankings provide a comparative summary based upon the analysis conducted in the four previous EPAR briefs, statistical analyses of historical yield and climate data, and future climate model predictions. According to the indicators analyzed, our research suggests that maize leads the cereal crops in terms of importance within SSA and in terms of research and policy attention. Our analysis of climate conditions and the crop’s physical requirements suggests that many maize-growing areas are likely to move outside the range of ideal temperature and precipitation conditions for maize production. Rice is the third most important crop in terms of consumption dependency, fourth in terms of production, but second only to maize in terms of research funding and FTEs. Sorghum and millet rank second and third in production importance and second and fifth in consumption importance, but rank below maize and rice in terms of FTE researchers. Their role is complicated by the fact that they are often considered inferior goods; SSA consumers often substitute away from sorghum and millet consumption if they are able to do so. Wheat is the least-produced crop of the five, and the second to last in terms of consumption importance. However, it still ranks above millet in terms of FTE researchers.

EPAR Research Brief #51
Publication Date: 07/02/2009
Type: Research Brief
Abstract

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.

EPAR Research Brief #32
Publication Date: 06/30/2009
Type: Literature Review
Abstract

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.

EPAR Research Brief #40
Publication Date: 06/29/2009
Type: Research Brief
Abstract

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. 

EPAR Research Brief #39
Publication Date: 06/05/2009
Type: Research Brief
Abstract

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.  

EPAR Research Brief #38
Publication Date: 06/01/2009
Type: Research Brief
Abstract

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.