Abstract:Studies on the spatial-temporal dynamic changes of fertilizer use and its eco-economic rationality in major grain production areas of China were made in order to provide some references for dealing with fertilizer's non-point pollution, reduction of fertilizers and grain production safety. Based on the data of fertilizers consumption, crops sowing areas and grain yields during 1993-2017, fertilization eco-economic appropriate amount (FEAA) model and fertilization environmental safety coefficient (FESC) model were established to form the method to assess the rationalities of fertilizer use in major grain production areas of China. The results showed that the fertilization intensities in major grain areas of China increased from 205.5 kg/hm2 in 1993 to 319.9 kg/hm2 in 2017 and the fertilization intensities of nitrogen (N) , phosphorus (P) and potassium (K) increased from 133.8, 48.0, 23.7 kg/hm2 in 1993 to 162.6, 84.2, 73.2 kg/hm2 in 2017, respectively. Proportion of N:P:K was from 1:0.4:0.17 in 1993 to 1:0.52:0.45 in 2017. FEAAs increased from 217.4 kg/hm2 in 1993 to 300.6 kg/hm2 in 2017. The fertilization intensities of N had been above the FEAA in 1993, P was above the FEAA from 2001, and K was close to its FEAA from 2009. So the higher risks of non-point pollution of N and P obviously existed. Shandong, Jiangsu and Henan Province were the highest fertilization intensity center during 1993-2017, with other sub-intensity provinces around. In 2017, Henan Provine had the highest fertilization intensity with 462 kg/hm2, while Helongjiang Province had the lowest fertilization intensity with 170 kg/hm2. Among the 13 provinces of grain production areas, 7 areas, Henan, Jiangsu, Shandong, Hubei, Hebei, Anhui and Inner Mongolia, were all individually beyond their own FEAAs with their fertilization efficiencies lower than the average in 2017, while the other 6 areas were close to or less than their FEAAs with their fertilization efficiencies higher than the average, especially Jilin and Hunan Province was with win-win development of grain production and environmental safety. In 2017, Henan belonged to eco-economic irrationality area due to overuse of fertilizers; Hebei, Jiangsu, Anhui, Shandong and Hubei Province belonged to economic rational and ecological irrational areas of fertilization; Hunan, Jilin, Liaoning and Inner Mongolia belonged to eco-economic rational areas of fertilization. Heilongjiang, Sichuan and Jiangxi Province were ecological rational and economic irrational fertilization areas because of insufficient fertilizer use. So there were great differences of fertilization intensities and rationalities in major grain production areas of China. Overall, the fertilizers were overused in China, but some areas were underused. Governments at all levels should classify the major grain production areas into different sorts of fertilization, and determine the categories of overused, rational used or insufficient used in fertilization. Guidance should be given to farmers to upgrade the grain yield and prevent fertilizer's non-point pollution, and organic fertilizers should be encouraged to use, and the construction of fertilization standards and information services should be reinforced.