| We use the mean value and variation coefficient model to analyze the spatial-temporal feature of grain production in 31 provinces from the year 1980 to 2006. Time series of grain production is divided into 3 stages according to the average yield and the variation coefficient of grain production in provincial level, which are the lower yield and higher variation stage, the higher yield and lower variation stage and the higher yield and higher variation stage. We classify the grain production of each province into four types according to the grain production level and the annual variation characteristics: the lower yield and higher variation type, the lower yield and lower variation type, the higher yield and lower variation type and the higher yield and... |
