在蔬菜露地栽培中,施用的肥料除被蔬菜吸收一部分外,剩余部分大多被雨水冲游流失掉,残留在土壤中的也是很少一部分。而大棚栽培则不同,由于大棚上有塑料薄膜的阻隔,棚内土壤不受雨水的直接冲刷,剩余肥料便全部残留在土壤中。肥料中盐类物质的常年集积,使得土壤溶液浓度过高,最 In the open-field cultivation of vegetables, the applied fertilizers are partly absorbed by the vegetables, and most of the rest are lost by the rain and washed away, and a small part remains in the soil. The greenhouse cultivation is different, due to the shed plastic film barrier, shed soil from the direct erosion of the rain, the remaining fertilizer will all remain in the soil. Perennial salt fertilizer accumulation, making the soil solution concentration is too high, most