Regional Charactristics of Productivity of Paddy-Field Rice in Japan

Abstract

Rice, especially paddy-field rice, is produced in most parts of Japan. Its production occupies as much as 52% of the total value of agricultural output, and therefore, rice is the most important product of Japan's agricultural industry, and plays a predominant role in the economy of individual farms.This study was aimed at investigating the increase in rice productivity by periods (see Fig. 1), and the regional difference in rice productivity in each period in order to determine the regional development of the increase in rice productivity during the period of 1883 to 1959.As a result of such an investigation it is evident that several regions with high productivity appeared in very small areas here and there in early days and after that regions become gradually larger regional group expanding into the environs. When such groups of high productivity region extended to the vast part of the country, their level of productivity should not be regarded as high but as the general level. After then, a new high productivity region appears.Repeating such cases, in early days, highly productive regions were found at the central part of Honshu (see Fig. 2). But they moved to the western Japan, such as Osaka, Nara and Saga prefectures which showed remarkably high productivity periods (see Fig. 10). During and after Second World War the center of high productivity moved again to the eastern Japan, and such as Yamagata, Yamanashi, and Nagano prefectures. where high productivity was shown when the weatern Japan was keeping its productivity at the general level. Thus the highly productive regions have shifted from western to eastern Japan (see Fig. 14).This study reveals that the national average yield per tan of rice increased though to a varying extent in different regions.The above conclusions can not be reached only by tracing historical development of the average yeild per tan in the whole country nor can the formation of high productivity regions be explained unless one has explored the agricultural structure in each of those regions.