Essays on the economics of cotton production in Zimbabwe: Policy implications for technology adoption, farmer health and market liberalization.

摘要

Cotton is grown in more than 30 Sub-Saharan African (SSA) countries and is a vital source of employment, foreign exchange and raw material for textile industries. But cotton industries in Africa face several strategic threats. In Africa, and in particular in Zimbabwe, long-term viability of cotton production will depend on both sustainable technology and policy. A key part of technological sustainability is mitigation of pesticide-related farmer health risks. Integrated Pest Management (IPM) provides some tools to reduce pesticide risks, but why farmers do not adopt IPM in African cotton production is less understood. In the policy arena, both economic and military policy can affect agricultural production. Zimbabwe's cotton sector has faced important policy shocks from Structural Adjustment Programs (SAPs) and the end of civil conflict in neighboring Mozambique.; The first essay analyzes acute health effects associated with pesticide use in two cotton-producing zones of Zimbabwe. The initial cost of illness regression model shows that farmer's reported acute symptoms are key determinants of farmer health costs. Poisson regression model results reveal that pesticide-induced acute symptoms are linked to the most toxic pesticides, use of leaking sprayers, label illiteracy, alcohol intake, and taking meals in the fields after spraying. Exposure averting and mitigating strategies that significantly reduce the incidence of acute symptoms include protective clothing, knowledge of first aid and predisposition toward reform calendar-based spray strategies.; The second essay examines determinants of cotton-IPM adoption in the same two zones. Results from a Poisson model shows that farmer's knowledge is the most important factor influencing the uptake of IPM technology. Pesticide-related health risks played no significant role in the adoption of IPM technology.; The third essay analyzes the determinants of Zimbabwe's cotton supply since 1980. It finds that SAPs have a negative impact on cotton acreage for both the large-scale commercial and small-scale communal farmers. Results show that large-scale cotton growers respond strongly to economic incentives while institutional factors matter for small-holders. Cessation in 1992 of the conflict in Mozambique is associated with positive cotton supply response among Zimbabwe's small-holders. Opportunities for cotton expansion lie with widespread diffusion of technical innovations and refinement of the on-going SAPs in order to generate positive supply response in future.