Joint production of rice and aquatic animal food species: Policy implications for pesticide use in Vietnam.

摘要

In recent years, the use of pesticides in the Green Revolution has become increasingly controversial. While the benefits of pesticide use in terms of preventing crop losses and increasing food grain production have been well recognized, its unwanted side effects on human health and environment have become a major concern. Two types of problems have traditionally been at the center of the debate. First, pesticides may have detrimental effects on human health and wildlife. Second, pesticide use may exacerbate pest problems rather than reduce them. More recently, a third issue has emerged as a concern: the possibility that pesticide may harm the growth of aquatic animal species that can provide an important biological control against rice pests.;The study revisits the issue of pesticide effects on rice production taking into account two particular shortcomings of current studies: potential adverse effects of pesticides and their impact on rice and animal food harvests. The non-parametric data envelopment analysis (DEA) programming technique is used in this study to approximate a multi-output production technology as well as derive efficiency measures. For this study, DEA is used mainly to sidestep problems of estimating a primal multi-output production technology.;The study addresses the following questions emerging for the current literature on pesticide effects on rice production: (1) Do pesticides reduce the productivity of joint rice and animal food production? (2) If so, should pesticides be reduced to improve productivity? (3) How should they be reduced? These questions provide important policy implications for pesticide use in rice farming in Vietnam.;The analyses in this study indicate that all three types of pesticides---herbicides, insecticides, and fungicides can impair joint rice and animal food productivity. Furthermore, the analyses find that reducing early insecticide spray does not improve the current allocation of pesticide inputs, but does increase economic efficiency in certain seasons. Finally, the analyses show that given the prevailing prices in the two seasons, over 90 percent of the farmers sampled did not apply profit-maximizing amounts of pesticides in both seasons; less than 5 percent applied pesticides at profit-maximizing levels. The remainder was roughly equally divided between those using more than the profit-maximizing amounts and those using less.