Refining the Positive and Negative Externalities of Taiwanese Paddy Rice Production

Abstract

"Rice is often singled out as the largest consume of irrigation water. There is also incresing acceptance of the fact that paddy irrigation yields social benefits beyond those directly resulting from rice production. But there is considerable dispute about the magnitude of those benefits. The dispute results in part from lack of relevant data and in part from the use of inappropriate methodologies. This paper outlines the issues associated with the valuation of externalities, identifies the sources of external benefits and costs in paddy rice culture, and reviews the problems associated with various methodological approaches. The authors conclude that there is a general misconception of the amount of water depleted by rice cultivation, and that return flows from rice cultivation generate important positive as well as negative externalities. However, existing studies may overestimate the potential benefits of paddy rice cultivation. There is a need for a new more objective methodological approach, but in many instances data may often be lacking for the successful application of this approach."