Livelihoods, food security and environmental risk: Sack gardening in the Kibera slums of Nairobi, Kenya.

摘要

This dissertation research examined the impacts of a particular form of urban agriculture, sack gardening, in the Kibera slums of Nairobi, Kenya. Urban agriculture is often promoted as a means of addressing urban food insecurity, but because slum dwellers in Nairobi generally lack access to plots of land to farm, this activity has remained largely inaccessible to them. Sack gardening, a relatively novel form of urban agriculture in the Kibera slums, involves planting various crops into the top and sides of large plastic sacks filled with soil, which allows people to plant a larger number of plants into relatively small spaces by making use of the vertical space occupied by the sacks. While urban agriculture has great potential to address urban food insecurity, there are also potential risks associated with farming in urban environments that lack formal waste and sanitation systems. Households that consume produce grown in urban environments are potentially exposed to a range of environmental contaminants, including heavy metals and biological pathogens. This dissertation investigated the trade-offs between urban agriculture as a means of improving local livelihoods and increasing household food security, and as an activity that potentially exposes people to a variety of environmental risks. My research on sack gardening in Kibera used a mixed methods approach, drawing on qualitative interviews, household surveys, focus group discussions and an analysis of plant, soil and water samples.;This research demonstrated that sack gardening is a viable livelihood strategy in the Kibera slums that can be integrated with other household livelihood strategies, and that farmers in Kibera were able to successfully integrate sack gardening into their urban livelihood strategies. I found that sack gardening contributed to improved household food security directly. Farming households consumed a greater variety of vegetables than non-farmers, including many indigenous vegetables, which have broader nutritional benefits and are culturally preferred to the kale, swiss chard and cabbage which are consumed by most households in Kibera. Farmers reported feeling more food secure than non-farmers, and sack gardening also resulted in an increase in social capital, which helps food security indirectly.;This research demonstrated that farmers' perceptions of environmental risks focused primarily on visible contaminates, while the major contaminants found in samples of vegetables from their sack gardens were heavy metals, often at concentrations above the recommended levels for human consumption. The disconnect between farmers' perceptions of environmental risk and actual risk raises questions about how to appropriately promote urban agriculture within urban areas as well as the trade-offs inherent with farming in densely populated and polluted urban areas.;While this research is based on a case study of urban agriculture in one slum in Kenya, it demonstrates both the potential benefits and risks associated with farming in an urban environment. Additionally, it suggests that policy makers and development organizations who promote urban agriculture as a means of improving urban food security need to be cognizant of the socioeconomic context and ecology of the urban environments in which this activity will take place.