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当今,谁不知干旱缺水对农业的危害?干旱是我国历史性的灾害,具有发生频率高、分布地域广、延续时间长、威胁危害大的特点.我国干旱、半干旱地区约占国土面积的47%,约占全国土地面积的51%,每年农田受旱面积多时达4～6亿亩,一般年份也都在2亿亩上下.我国北方干旱缺水地区长期饱受“十年九旱”之苦,南方广大地区亦经常遭受伏旱之灾,干旱是造成我国粮食减产的主要气象灾害.
Nowadays, who do not know the drought and water shortage harm to agriculture? Drought is a historic disaster in our country, which has the characteristics of high occurrence frequency, wide geographical distribution, long duration and great threat threat.China’s arid and semi-arid areas occupy the land area 47%, accounting for 51% of the country’s land area, annual farmland drought area for up to 4 ~ 600000000 acres, the general year also in 200000000 acres.China’s northern arid and dry areas have long been suffering from “ten years nine drought” The hardships in the vast areas of the South are also frequently affected by drought. Drought is the major meteorological disaster that has caused the reduction of grain output in our country.