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北京市蔬菜塑料大棚是从七十年代初期开始发展起来的,至今已有十二年历史。十几年来发展速度很快,据近郊统计,七二年127亩,七四年近1000亩,七八年3100亩,八○年4600亩,八二年6500亩,八三年发展到8500亩。由于大棚的出现和发展,使蔬菜保护地生产发生了巨大变化。大棚生产能提早、延后蔬菜生产和上市时间,提高蔬菜产量、调剂淡季,
Beijing vegetable plastic greenhouse from the early 1970s began to develop up to now, has 12 years of history. According to statistics from the outskirts of the country, there are 127 mu in seventy-two years, nearly 1,000 mu in seventy-four years, 3100 mu in seventy-eight years, 4600 mu in 1980, 6500 mu in 1982 and 8500 mu in 1983 . Due to the emergence and development of greenhouses, great changes have taken place in the production of vegetable protection areas. Greenhouse production can be earlier, delay the production and marketing of vegetables, increase vegetable production, adjust the off-season,