粮食水旱灾害减产评价分析方法及中国粮食减产实证分析

Evaluation Method of Grain Reduction Caused by Droughts and Floods and Empirical Analysis of China Grain Reduction

在对现有粮食减产分析方法述评的基础上,建立了新的粮食减产率和减产量评价指标公式,分析了中国1978-2013年间的粮食水旱灾害减产率、减产量时空分布情况,设定了粮食减产等级与界限划分标准,识别了中国重大以上粮食减产年份和地区,提出了中国降低粮食因灾减产的建议。结果表明,36年间:(1)中国年均粮食旱灾减产率6.7%,有11年减产率超过8%,为重大以上减产年份;(2)中国年均粮食水灾减产率3.3%,有9年减产率超过4%,为重大以上减产年份;(3)中国累计粮食旱灾减产115 535万t,年均减产3 209万t,有9年减产超过4 000万t,为重大以上减产年份;(4)中国累计粮食水灾减产56 422万t,年均减产1 567万t,有7年减产超过2 000万t,为重大以上减产年份;(5)中国29个省市区中,有14个省区粮食旱灾减产重大以上,有10个省区粮食水灾减产重大以上,有6个省区同属于重大以上粮食水旱灾害减产地区。

Based on the commentary of existing grain reduction evaluation analysis method, we establish a new index evaluation formula of the rate and the production of grain reduction, analyze the spatial and temporal dis- tribution of China＇ s grain reduction caused by droughts and floods from 1978 to 2013, set criteria for the classifica- tion levels and limits of grain reduction, identify China＇ s major grain reduction areas and the year, and put forward proposals for China to reduce grain reduction. The results show that during the 36 years ： （1）China＇ s annual grain reduction rate caused by droughts was 6.7% , including 11 years was more than 8% , was a major oler reduction year; （2）China＇ s annual grain reduction rate caused by floods was 3.3%, including 9 years was more than 4% , was a major over reduction year; （3）China＇ s total grain reduction caused by droughts was 1. 15535 billion tons, with an average annual reduction of 32. 09 million tons, including 9 years over 40 million tons, was reduction years over major; （4）China＇ s total grain reduction caused by floods was 564.22 million tons, with an average annual re- duction of 15.67 million tons, including 7 years over 20 million tons, was reduction years over major; （5）Among 29 Chinese provinces, cities and districts, 14 provinces grain reduction caused by droughts was major and above, 10 provinces grain reduction caused by floods was major and above, 6 provinces district belonged to major and above grain reduction areas caused by droughts and floods.