An Economic Rationality of Green Manure Cropping in Large-Scale Upland Farming

摘要

We examined the rationale of introduction and continuation of fallow green manure cropping in large-scale upland farming. First, the decision on the introduction of fallow green manure cropping depends on the scale of farming in terms of farming areaand, if introduced, the acreage of such crops represents around 5% of the total acreage. Second, although the introduction of fallow green manure, which is a non-cash crop, causes decline in direct profitability, overall costs are reduced. Therefore, fewdifferences in income per unit area were found among the cases of continuous, non-continuous, and non-introduction of fallow green manure cropping. In other words, there are few grounds for concern over a decline in profitability, for the hailing or noncontinuation of fallow green manure cropping because of the availability of crop subsidies. Third, unbalanced crop compositions are observed in the cases of non continuation fallow green manure cropping, indicating the difficulty in establishing a croprotation. These problems are not found in the cases of continuous fallow green manure cropping despite low productivity and profitability.