Graduation Year

2016

Document Type

Dissertation

Degree

Ph.D.

Degree Name

Doctor of Philosophy (Ph.D.)

Degree Granting Department

Engineering

Major Professor

James R. Mihelcic, Ph.D.

Committee Member

Maya A. Trotz, Ph.D.

Committee Member

Fenda Akiwumi, Ph.D.

Committee Member

Norma Alcantar, Ph.D.

Committee Member

Tara Deubel, Ph.D.

Keywords

Life Cycle Assessment, Gender, Geographic Information Systems, Ethnography, Sustainable Development Goals

Abstract

Millions of people in the world, particularly women and people in sub-Saharan Africa, suffer from hunger and poverty. Three of the major 2015-2030 United Nation’s Sustainable Development Goals (SDGs) aim to eliminate hunger through food security and sustainable agriculture, eradicate poverty, and achieve gender equality through women’s empowerment. Shea trees and their associated fruit and butter can play a major role in each of these three SDGs for women and their families throughout sub-Saharan Africa. Shea trees are located over a wide expanse stretching more than 5,000 kilometers across over eighteen countries in sub-Saharan Africa. These trees produce fruit that encase a kernel within a nut from which shea butter can be extracted. Shea butter production is unique in that it is predominately controlled by women and they utilize the profits they earn from selling the nuts or butter for items to support their families such as purchasing grain for depleted stores during the hungry season and paying for children’s school fees or clothing. Shea butter is also cited as a sustainable oil compared to other world oils such as peanut, palm, soybean, or cocoa butter which require heavy land use land change and fertilization while shea trees often grow in existing fields or fallows without fertilization, application of pesticides, or clear cutting of forests. However, shea butter production is still human and material energy intensive, requiring substantial amounts of firewood to heat and dry the shea nuts and the shea tree distribution and associated shea butter production and role in African livelihoods is under threat from the increasing effects of globalization and climate change.

Thus, this dissertation fills in important research gaps in the existing literature on shea (Vitellaria paradox and nilotica) and sustainable development by developing and implementing methods to model food security, energy, and climate and cultural impacts of a process using shea butter production as a case study. To begin, the first comprehensive shea tree land suitability model to estimate potential shea production and amount of women collectors was created using Geographic Information Systems (GIS) that combined eight parameters: land use, temperature, precipitation, elevation, Normalized Difference Vegetation Index (NDVI), soil-type and soil-drainage. Even under conservative estimates, the model produced an extensive shea tree suitability area of 3.4 million square kilometers with 1.8 billion trees in 23 countries and over 18 million women collectors, encompassing a total population of 112 million. Next, this dissertation improved the global application of Life Cycle Assessment (LCA), a tool used to measure the entire environmental impacts of a process from extraction of materials through end-of-life stages, by utilizing a hybrid-LCA methodology that incorporated human energy and embodied energy and emissions from firewood of five traditional and improved shea butter production processes common throughout West Africa. When the LCA results of shea butter production were compared to other LCA studies of world oils, shea butter performed better in abiotic depletion and human toxicity impact categories as well as global warming potential when indirect land use land change was considered. Nevertheless, a large amount of human and firewood embodied energy and emissions were involved in shea butter production. However, mechanization of certain production steps was found to significantly reduce human energy without increasing total embodied energy. Furthermore, improved cookstoves modeled in this dissertation could reduce global warming potential, human toxicity, and embodied energy by 77-78%, 15-83%, and 52% respectively. These results would not have been captured in traditional LCA methodology and this was the first study to compare process-based and economic input-output LCAs in a developing country with very different reliance on and accessibility to resources than developed countries.

Finally, an in-depth ethnographic study was conducted in this dissertation, combining qualitative and quantitative methods to better understand the importance of shea butter to African’s livelihoods in the context of food security and climate change. Shea butter was found to have a vital role in the maintenance and development of social bonds between female friends and family as well as an integral role in all religious and traditional ceremonies including a special shea ceremony. Additionally, 93% of survey respondents agreed there has been a decrease in shea fruit yields during their life time, 80% of which believed this was attributed to decreased rainfall. Moreover, 83% of 181 shea trees sampled were found to have an invasive vine species, drying out and/or have large worms. Therefore, recommendations derived from this dissertation for development agencies, governments and industry include further research on and promotion of: parkland management, preservation, and regeneration as well as reduction in the amount of human energy and firewood in shea butter production by providing better access of women collectors to mechanization, improved cookstoves, and transportation (i.e. donkey carts and bicycles) for harvesting shea fruit. Overall the research developed in this dissertation contributed significantly to the existing literature on shea and developed methods and a framework that has applications for achievement of the UN’s SDGs for 2030 particularly to obtain food security.

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