城市污泥堆肥对蔬菜幼苗的盐害及其淋洗脱盐效果

Salt Damage of Municipal Sludge Compost to Vegetable Seedlings and Its Leaching Desalinization

以番茄、甜椒和黄瓜为供试对象，考察了污泥堆肥作为育苗基质对蔬菜幼苗的盐害作用及其淋洗脱盐效果。结果表明，污泥堆肥的盐分含量偏高，尤以Na^＋和Cl^-浓度较高，对植物产生明显的盐害作用，导致植物的生长受阻；用水淋洗以降低污泥堆肥中水溶性盐分后，蔬菜幼苗长势明显改善，株高、茎粗和生物量增加，其中，蔬菜株高增加了2～3倍，生物量增加了3—7倍，达到甚至超过土壤对照的育苗效果；在本试验条件下，淋洗脱盐的用水量控制在堆肥质量的2—3倍为宜。

Taking tomato, sweet pepper and cucumber as study objects, the salt damage of municipal sludge compost as seedling substrate to vegetable seedlings and its leaching desalinization were investigated. The high salinity, especially Na^＋ and Cl^- in municipal sludge compost has a significant salt damage to plants, which causes inhibition of plant growth. After water leaching for reducing the soluble salt content in the compost, the growth of vegetable seedlings is significantly improved. The biomass, shoot height and stem diameter of these vegetables are all increased. Among these indicators, the shoot height and biomass are increased by 2 to 3 times and 3 to 7 times respectively, which reaches or exceeds the seedling raising effect in control soil. In this research, the water consumption for leaching desalinization should be controlled at 2 or 3 times of compost mass.