Date of Award
Doctor of Philosophy
Environmental Resources & Policy
Sorghum is the fifth most produced crop worldwide, yet despite its exceptional advantages over other major cereals, its inferior reputation and low commercial value have left it under-represented in both research and the international market. The importance of subsistence sorghum calls for targeted research on the local relationships between agriculture and the surrounding environment to establish and quantify the impacts of major players on sorghum output. This three-article style dissertation investigates the major factors that impact sorghum production, with a focus on northern Nigeria in the West Sahel. In the first study I explored the developments in sorghum production within six major producing countries across the globe and identified key factors that have notable effects on overall sorghum production. Next, I employed a time-series analysis to determine the responses in sorghum yield induced by a set of variables in nine northern Nigerian states based on historical trends. Finally, I investigated the association between the spatial distribution of sorghum yield and a separate set of explanatory variables, whilst comparing the results and performance of different spatial multivariate methods. The results revealed ten major influential factors that impact sorghum production within the leading production regions: climate change, agricultural input, population/economic growth, biodiversity, agricultural resource scarcity, other crop demand, price, non-food demand, cultural influence and armed conflict. In northern Nigeria, precipitation, temperature and soil moisture were shown to have substantial temporal and spatial influences on sorghum production. There was also evidence on the important roles played by producer price and genetic variation in the abundance and distribution, respectively, of sorghum production in the study area. These findings imply the need to increase efforts in soil conservation programs and champion the adoption of soil-moisture-dependent masakwa cultivation of sorghum wherever appropriate. Sustaining lucrative producer prices and encouraging the trading of seeds to promote genetic variation are likely to lead to improved sorghum yield in the area. However, the development of policies that bind government and intuitional agencies to the commitment of improvements in farmer welfare would also be critical. Post production support would include: development of better and safe transportation routes to reduce high transportation costs, price stabilization, improved sorghum markets and establishment of local trade associations. Future inquiries can be further focused on more localized investigations that further develop the description of the location–specific variables impacting sorghum production and the nature of their influence on sorghum yield in these vulnerable regions.
This dissertation is only
available for download to the SIUC community. Others should contact the
interlibrary loan department of your local library or contact ProQuest's Dissertation Express service.