保护地施肥量大,一部分被作物吸收,其余部分、尤其是化肥的一些盐类离子残留在土壤中。因环境封闭,这些离子随水分上移积累在土壤表层,直至妨碍根系对水分、养分的正常吸收造成盐害。被害蔬菜症状表现为:植株矮小、生育不良、叶色浓绿、有时叶表面覆盖一层蜡质,严重时从叶缘开始枯死或变褐内卷。 Large amount of fertilizers are protected, some are absorbed by crops, and the rest, especially some salt ions of fertilizer, remain in the soil. Due to the closed environment, these ions accumulate in the soil surface with the water up, until the root prevents the normal absorption of water and nutrients cause salt damage. Victims of vegetable symptoms are: short plants, poor fertility, leaf color dark green, sometimes covered with a layer of wax leaf surface, in serious cases from the edge of the leaves began to die or brown in the volume.