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近几年来,京郊冬春蔬菜生产有了较好的发展。原因之一是薄膜小棚(有的地方叫改良阳畦)的发展较快。据调查,目前京郊小棚有几千亩。1981年单按改良阳畦的名义统计的就有2046亩,已成为保护地的一个重要类型。一.结构:薄膜小棚,是有土墙的小型半拱棚:它由上墙,拱架组成,薄膜覆盖,用草帘保温,因而有较好的保温效果,在京郊,可以不加温在冬季栽培芹菜,在早春栽培蕃茄,上市期比大棚早,而有较好的经济效益。土墙:位于北边。一般高0.7～1.0米,底宽0.6～0.7米,面宽0.3～0.4米。它的高矮与
In recent years, the winter vegetable production in Beijing suburbs has a good development. One of the reasons is the rapid development of film sheds (in some places called improved sunburst). According to the survey, there are several thousand mu of shed in the suburbs of Beijing. In 1981, according to the name of Yangyang improved single count of 2046 acres, has become an important type of protected area. I. Structure: thin film shed, is a small half-wall soil wall shed: it consists of the wall, the arch frame, covered with film, with straw curtain insulation, which has better insulation effect in the suburbs of Beijing, you can not warm Celery cultivation in the winter, tomato cultivation in early spring, listing period earlier than the greenhouse, and have better economic benefits. Earthen wall: located on the north side. Generally 0.7 to 1.0 meters high, the bottom width of 0.6 to 0.7 meters, 0.3 to 0.4 meters wide. Its height and