蚌埠地区设施土壤盐分累积特征研究

Study on Salt Accumulation in Greenhouse in Bengbu Region

对蚌埠市怀远和固镇两地不同年限设施土壤的盐分累积特征进行了研究,测定了土壤剖面各层次中的盐分总量和Na^＋、K^＋、NH4^＋、Ca^2＋、Mg^2＋、NO3^-、H2PO4^-、Cl^-、SO4^2-、HCO3^-等10种离子的含量,根据这10种离子之和与盐分总量的比值计算＂盐分回收率＂。结果表明,大棚内土壤表层的盐分总量是露地土壤相同层次的2.4-5.7倍,盐分主要聚积在0-15cm土层中,尤其是0-5cm层次中;随着大棚使用年限的延长,盐分总量有增加趋势;除Na^＋和HCO3^-外,NH4^＋、Ca^2＋、Mg^2＋、NO3^-、H2PO4^-、SO4^2-在大棚表层土壤中都有明显的累积,尤以Ca^2＋和NO3^-累积严重,怀远大棚表层土壤的Ca^2＋和NO3^-占盐分离子总量的63.8%,固镇大棚表层土壤的K＋、Ca^2＋和NO3^-占盐分离子总量的73.3%;根据＂盐分回收率＂推断,除了本文测定的10种离子外,还有相当数量（约占总盐的15%-23%）的其他重金属离子和非金属离子存在于大棚土壤中。

The salt accumulation and ion composition in greenhouse soils were studied by investigating content of total salt and Na^＋ ,K^＋ ,NH4^＋ ,Ca^2＋ ,Mg^2＋ ,NO3^- ,H2PO4^- ,Cl^- ,SO4^2- ,HCO3^- in the soil profiles in Bengbu region of Anhui Province. According to these ions and total salt recover ratio is computed. The results indicated that salt content in greenhouse soils was higher than that in open field soils. Salt in surface soil of the greenhouse was 1. 4 -4.7 times higher than that in the neighboring open field surface soil. Salt accumulation in the green- house soil profiles was chiefly in 0 - 15cm layers particularly in 0 -5cm layer. Salt accumulation was serious in the old greenhouse soils such as 10a or older greenhouse soils. The longer the age of the greenhouse was, the higher salt content was in the soils. Apart from Na^＋ and HCO3^-, the content of NH4^＋, Ca^2＋ , Mg^2＋ , NO3^-, HEPO4^- , Cl^- , SO4^2- increased significantly in the greenhouse soils. Ca^2＋ and NO3^- were the major ions in the soils. They were 63.8% of total salt in greenhouse soils in Huaiyuan. K^＋ , Ca^2＋ and NO3^- were 73.3% of total salt in greenhouse soils in Guzhen. According to the salt recover ratio, it can be guessed that there are some other ions in the greenhouse soils apart from the 10 ions mentioned above.