沼液排放对土壤质量的影响

为探讨沼液排放对土壤质量的影响,对比研究了沼气站周边在不同沼液影响频率下的土壤容重、酸碱度和有机质、全氮、全磷、全钾含量。结果表明,受沼液影响的土壤质量发生了变化,其中长期受沼液排放影响的土壤、人工每年灌溉4次沼液的土壤的有机质、全氮、全磷、全钾含量均有一定程度的增加,土壤容重降低,酸碱度变化不大;与海南省砖红壤农田平均水平相比,受沼液排放影响的土壤的有机质、全氮、全钾含量明显增高,全磷含量偏低,说明长期排放沼液已经造成了土壤氮、钾盈余,磷缺乏,养分供给不平衡。

Effect of Slurry on Soil Quality

The soil under daily slurry flow （ Treatment 1 ）, seasonal slurry flow （ Treatment 2） and control without slurry flow （Treatment 3 ） under the natural condition around the biogas factory was sampled to analyze soil bulk density, pH, organic matter, total P and total K. The results show that the soil in Treatments 1 and 2 with slurry flow was changed in soil quality. The soil organic matter and total N, total P and total K content were higher and the soil bulk density was lower in Treatments 1 and 2 than in the Treatment 3 （ the control）. The soil pH changed little among the treatments. The treatments 1 and 2 had obviously higher organic content and total N and total K content but lower total P content than the lateritic soil in the paddy field, which indicates that long term flow of slurry resulted in soil nutrient imbalance due to excessive buildup of soil N and K and deficiency of P.