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目前,世界各地每年发生的林火有20多万次,烧毁森林面积数百万公顷。美国每年发生12.7万多次森林火灾,火烧面积达120万公顷,平均每次火灾面积为9.5公顷,估计每年林火造成的损失及护林防火的费用在4～6亿美元之间。加拿大的森林火灾每年平均7,000多次,森林火烧面积约118.5万公顷,每次火灾平均面积为155公顷。其它国家如苏联、澳大利亚、意大利、日本及法国等,森林火灾也很
At present, more than 200,000 forest fires occur every year in the world, burning millions of hectares of forest area. In the United States, there are more than 127,000 forest fires each year, with an area of 1.2 million hectares of fire burning and an average area of 9.5 hectares of fire per year. It is estimated that the annual loss caused by forest fires and the cost of forest fire prevention will be between 400 million and 600 million U.S. dollars. Forest fires in Canada average more than 7,000 times per year, forest fires cover an area of about 1.185 million hectares, and the average area per fire is 155 hectares. Other countries such as the Soviet Union, Australia, Italy, Japan and France, the forest fire is also very