Graduate School of Agricultural and Life Sciences, The University of Tokyo

Authors

Yuki Sofue, Ryo Kohsaka*

Abstract

The significant decline and ageing of Japan's rural population has severely affected the maintenance of agriculture in these areas, resulting in the abandonment of agricultural land and subsequent conversion to other land use types. Dr. Yuki Sofue and Prof. Ryo Kohsaka quantified the change of land use in Matsusaka City, Mie Prefecture, located along the former Wakayama-kaido Road and in the Kushida River watershed, and analyzed the factors that can affect the change of agricultural land area using Geographically Weighted Regression analysis. Using this method, it is possible to estimate for each location the factors most associated with changes in agricultural land, such as elevation and the rate of population change. In most cities and villages, agricultural land area has decreased, suggesting that the rate of change and potential factors vary by geographical location, and that policies such as subsidy systems may also contribute. Most of the agricultural land converted in the plains was converted to residential land, while a high percentage of agricultural land in mountainous areas was converted to forest land or waste land. In addition, agricultural land in mountainous areas tended to be converted more often to agricultural land located at lower elevations than agricultural land located at higher elevations. This suggested that the subsidy system, such as the direct payment system, may make it easier to maintain agricultural land in mountainous areas that are subject to subsidies and to convert agricultural land in the boundary areas of mountainous areas that are not subject to subsidies.