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据近年初步统计,我国每年林木病虫害发生面积达一亿二千万亩,大大超过同年造林面积,其中成灾需要防治的面积就有几千万亩。每年要付出巨大的防治费用。
According to preliminary statistics in recent years, the annual area of forest pests and diseases in our country amounts to 120 million mu, which is much larger than the afforestation area in the same year. There are tens of millions of mu of area in need of prevention and control. Every year to pay a huge cost control.