丽水市蔬菜与茶叶基地土壤肥力及土壤环境质量综合评价

Comprehensive Assessment of Soil Fertility and Soil Environmental Quality of Vegetable and Tea Bases in Li Shui

为全面了解丽水市农业生产基地土壤质量情况,本研究以土壤肥力和土壤环境质量为评价指标,采用单因子指数与内梅罗指数相结合的方法对该市蔬菜和茶叶基地土壤质量进行综合评价。结果表明,蔬菜与茶叶基地耕层土壤全氮、速效钾含量充足,但速效磷平均含量和p H值的平均值分别为162mg·kg^(-1)、4.39和106 mg·kg^(-1)、3.77,土壤磷素均过量,且酸化严重。蔬菜基地全氮、速效钾以及土壤磷酸酶与脲酶活性均高于茶叶基地,土壤微生物数量低于茶叶基地。2个基地土壤中Cd、Pb、Cr、Cu、Zn、Ni、As、Hg、六六六及滴滴涕平均含量均低于国家土壤环境质量二级标准,其中Cd和Pb为潜在污染因子,蔬菜和茶叶基地综合污染指数分别为0.57和0.42。2个基地灌溉水与肥料重金属含量均低于国家相关标准,蔬菜及茶叶样品重金属和农残超标率均为0。综上,丽水市蔬菜与茶叶基地环境整体处于清洁水平。本研究为土壤质量综合管理提供了科学依据。

In order to get a comprehensive understanding of soil quality of agricultural production bases in Li Shui,both unidirectional index and inner merlot index methods were used to evaluate soil fertility and environmental quality of vegetable and tea bases. Results showed that total N and available K were sufficient in vegetable and tea bases,however,over-accumulated P and acidic conditions could be the problems in both bases,which were 162 mg. kg^-1,4. 39 and 106 mg. kg^-1,3. 77,respectively. The total N,available K and activities of phosphatase and urease of vegetable base were all higher than those of tea base,while the reverse was true for the soil microbial population. The soil pollutants,namely Cd,Pb,Cr,Cu,Zn,Ni,As,Hg,666 and DDT,in vegetable and tea base were all below the secondary standard of national soil environmental quality. Cd and Pb as potential polluted factors were observed in both bases. The integrated pollution evaluation index of vegetable and tea bases was 0. 57 and 0. 42,respectively. Heavy metals in the irrigation water and fertilizers from both bases were all lower than the national standard, and no contamination were found in the vegetable and tea samples in both bases. All of above monitoring results showed that vegetable and tea bases in Li Shui were at a clean level. This study integrated soil fertility and soil environmental quality into soil quality evaluation index system,providing a scientific basis for the comprehensive management of soil quality.