FACTOR DECOMPOSITION IN REGIONAL DISPARITIES OF GRAIN PRODUCTION IN JIANGSU PROVINCE

Based on the total grain yield computation model,grain production could be decomposed by 4 factors of cultivated land use,including the scale and the scope of utilization,the use structure and intensity change in cultivated land use.As a case study,the dynamics of Jiangsu's grain production are identified at provincialregional-city level respectively.The results show that: Since mid-1990s,the grain production of South Jiangsu shrinks due to decrease in sum and decay in yield function of cultivated land,whereas Central and North Jiangsu become granary because of increase in intensity of cultivated land use.The dominant contributing factor to the grain production differs in different cities: the intensive cultivation is the most remarkable factor in 5 cities in Central and North Jiangsu such as Lianyungang,the structure adjustment has the greatest impact on the change of grain production in Nanjing,Xuzhou,Nantong and Huaian,Suzhou and Wuxi mainly due to multiple-crop index.