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 #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 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 Technical Report #134
Publication Date: 04/10/2011
Type: Literature Review
Abstract

Agriculture is a principal source of livelihood for the Tanzanian population. Agriculture provides more than two-thirds of employment and almost half of Tanzania‘s GDP. Women play an essential role in agricultural production. The sector is characterized as female-intensive, meaning that women comprise a majority of the labor force in agriculture (54%). This brief reviews the academic and grey literature on gender and agriculture in Tanzania, providing an overview on the structure of households, the household structure of agricultural production, information on women’s crops, and gender and land rights in Tanzania. We conclude with a summary of challenges to women in agriculture, and of potential implications for women of advancements in production technology and other economic opportunities at the household level. 

EPAR Technical Report #133
Publication Date: 03/07/2011
Type: Literature Review
Abstract

This report provides a summary of Tanzania’s agriculture sector, crop production, agricultural productivity and yield levels, risks, and policies and reforms. This review uses resources found on the University of Washington Libraries system and Google Scholar, as well as the websites of the Government of Tanzania, FAO, and World Bank. We find that Tanzanian agriculture workers comprise 80% of the population and farm a wide variety of crops, ranging from staple crops such as maize, cassava, and rice, to export crops such as coffee, cotton, tobacco, tea, and sugar. Smallholder farmers face increasing risks from climate change, pests, diseases, and land degradation, among others. While they have some resources available, such as farmer groups and limited access to ICTs, they lack important resources such as credit and inputs. We find that Tanzania’s land tenure and agriculture policies may further complicate the lives of smallholders through increased taxes and administrative processes. Through the Agricultural Sector Development Programme (ASDP) reform, however, the Government of Tanzania hopes to empower farmers and improve service delivery.  

EPAR Technical Report #130
Publication Date: 01/29/2011
Type: Literature Review
Abstract

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.