「緑の革命」と所得分配

バングラデシュの灌漑水市場の分析を通じて

抄録

　Small-scale private investment in shallow tubewells has accelerated rice production during the 1980s in Bangladesh. It is now very common for tubewell owners to sell irrigation water to other villagers. The aim of this article is to analyze the distributional impact of the village-level groundwater market, based on the primary data collected in a Bangladesh village.
　It was found that the value of w/c (w: rate of water charge, c: operation and maintenance cost of irrigation per acre) is on average 2.59, which is quite high compared with other areas. However, analysis of net irrigation surplus, defined as gross rice product minus all input costs (including labor), showed that the water market is functioning rather well. The larger share to capital and the resulting smaller share to land is a reflection of the usurious interest rate in the informal credit market.
　Land-saving and capital-using bias of the "green revolution" technology has provided landless and marginal farmers with an opportunity to climb the social ladder. Particularly in rural areas with plenty of off-farm employment opportunities, the participation of lower strata villagers in usurious money lending (mainly to tubewell owners belonging to upper strata) is quite common. Even in the village surveyed, where off-farm activities are under-developed, the money flow related to usufructuary land transaction is apparently directed from the lower strata to the upper strata.
　Another implication of the technological bias is that the irrigated rice production is quite sensitive to market price. It was calculated that tubewell owners stop the water supply if rice price falls more than 18%. Therefore, rice self-sufficiency in Bangladesh may be quite vulnerable.