影响土地处理系统土壤硝化作用条件的探讨

Study on Some Fa(?)ors Affecting Nitrification in Soil of Land-Treatment System.

本文对影响天津市城市污水土地处理系统现场土壤硝化作用的一些因子进行了研究。结果表明,环境温度、酸碱度、土壤盐度及重金属镉(Cd^(2+))等都不同程度地影响土壤的硝化作用及其进行的程度。在一定温度范围内(5—30℃),随着温度升高硝化作用强度也逐渐增加;土壤盐度增加至0.5％时,对硝化作用抑制率为92.5％;pH值中性或微碱性时(pH7和pH7.5)硝化作用最强,pH4和pH10时对硝化作用抑制率分别为95.6％和87.9％,土壤Cd^(2+)含量达2.5μM/g土时,硝化抑制率达64.8％。

Some factors affecting the nitrification in soil of the Tianjin municipal sewage Land-treatment System are evaluated in the present paper. The results have shown that such factors as temperature, pH value, NaC1 concentration and Cd^(2+) content can influence the nitrification in soil and the degrees of such a biological reaction. The nitrification in soil will increase with the temperature rises from 5℃ to 30℃. The inhibition of nitrification is 92.5% at the NaC1 concentration of 0,5% in soil, It has the highest nitrification at pH7 and pH 7.5, with the inhibition rate of 95.6% and 87.9％ at pH 4 and pH 10 respectively. The inhibition rate is 64,8% at the soil Cd^(2+) concentration of 2.5μM/g soil.