Geographical distribution of China''s grain yield risk area
中国粮食产量不同风险类型的地理分布

Based on risk analysis theory,we make use of ISODATA method to divide China into different risk areas at the prefectural and provincial levels with risk-factor division index and synthetic division index respectively.The results show that the difference in risk levels in China relates closely to local disaster induced environment,disaster factors and productivity.The divi-sion results could serve as reference on resources utility,grain yield allocation and risk decision.