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最近十余年间,我国北方地区蔬菜保护地面积增长迅速,保护地的结构类型和作物的茬口安排逐渐趋于标准化、规范化。随着栽培枝术的改进,保护地蔬菜种植的经济效益普遍得到提高。目前,一个以薄膜覆盖为主体的蔬菜保护地栽培体系已基本形成,预计今后相当一段时间内,大中城市郊区保护地蔬菜面积仍将继续保持上升的趋势。一、蔬菜保护地的类型及其建筑结构北京地区蔬菜保护地的构成大体分为6
In the recent ten years, the area of vegetable protection in northern China has been growing rapidly. The structure types of protected areas and the stubble arrangement of crops have gradually become standardized and standardized. With the improvement of cultivation techniques, the economic benefits of vegetable cultivation in protected areas have generally been raised. At present, a cultivation system of vegetable protection mainly covered by thin film has basically taken shape. It is expected that the vegetable area in the protected areas of suburban areas in large and medium-sized cities will continue to maintain its upward trend for quite some time in the future. First, the type of vegetable protection and its architectural structure The composition of vegetable reserves in Beijing can be divided into 6