Changes in grain production in China since 1949 and major reasons

This paper consideres changes in grain crop production in China during 1949-1996, with particular emphasis on the reform period, i.e., 1978-1996, from the aspects of grain output, sown area, and yield. Data on cultivated land area from the Semi-detailed Land Use Survey and the Detailed Land Use Survey, which have good credibility in China, are used to correct the sown area and yield given in statistical yearbooks. Based on the above data, the authors considered the relationship between the production of different crop varieties and the reasons for their cultivation in different periods and regions. In addition to population growth, natural hazards and technological improvements, the following reasons have been found important for grain production: 1) The main reason for the shift from low-yield crops to high-yield crops varies by period. Before the reform, it was mainly caused by the great pressure of food demand induced by rapid population increase. After 1978, the main reason was the change in dietary structure. 2) Rapid urbanization since the 1980s has been a serious challenge to grain production in China. The amount of cultivated land has decreased because of urban sprawl. The opportunity cost of grain production has risen swiftly because of the rapid development of nonagricultural sectors, which deprives the agricultural sector of resources, such as investment and labor