构建湿地中试系统基质剖面微生物活性的研究

 对稳定运行的复合垂直流构建湿地中试系统基质进行分层采样,测定微生物数量,生物量氮,酶活性,硝化作用,反硝化作用以及呼吸作用等各项指标.结果表明,上行流和下行流池0～10cm的基质层中好氧微生物数量高出30～55cm的层面1～2个数量级;反硝化细菌除下行流池0～10cm的层面外其他基质层数量都达到10⁷个/g干土以上.0～20cm的基质层中脲酶活性明显高于30～55cm的层面;而0～10cm的层面中脱氢酶活性明显高出10～55cm的层面2～5倍.硝化反硝化作用广泛存在于基质中,硝化作用表现出一定的空间规律,0～10cm的基质硝化作用强度要比40～55cm层面的高出20%;反硝化作用的空间差别很小,其作用率最低也达到85.5%.

Studies on microbial activities of substrate in plot scale plot of constructed wetland

Microorganism amounts, biomass nitrogen, enzyme activities, nitrification, denitrification, and respiration were measured in separate layer samples of the substrate of stablely operating plot scale of integrated vertical-flow constructed wetland. Aerobic microorganisms amount in 0~10cm substrate of up-flow and of down-flow ponds were higher with 1~2 magnitudes than that in 30~55cm substrate; the amounts of denitrification bacteria reached over 107/g (dry soil) except those of down-flow pond. Urease activities in 0~20cm substrate were obviously stronger than those in 30~55cm substrate; and dehydrogenase activities in 0~10cm substrate were 2~5 times of those in 10~55cm substrate.Nitrification-denitrification existed widely in the substrate, and nitrification showed definite spatial regulations:nitrification strength in 0~10cm substrate was higher with more than 20 percents than that in 40~55cm substrate; thespatial difference of denitrification was very little, with its lowest action rate still reaching 85.5%.