Effects of Heavy Metals on Enzyme Activity and Bacterial Community in a Chromium Slag Field in Northern Guizhou

CHEN Yahang; SU Chunhua; ZHU Sixi; LUO Yuhong; XIA Guodong

doi:10.19672/j.cnki.1003-6504.0554.23.338

Abstract：This paper dealts with the study on the response mechanism of soil enzyme activity and bacterial phylum level abundance to heavy metal under the circumstances of long-term heavy metal pollution.The instruments including inductively coupled ion emission spectrometer,96 microplate fluorescence and Illumina MiSeq high-throughput sequencing were used to analyze the soil samples taken from five typical contaminated sites within a chromium slag field in northern Guizhou Province,involving heavy metals,enzyme activities and bacteria for the purpose of laying theoretical basis for the remediation technique of the mining area.As a result,the study showed that the study area was seriously polluted by three heavy metals the most,i.e.zinc,nickel and chromium,and the area most disturbed by human factors was in the lower reach of the river basin,followed by the upper reach.The activities of sucrase and urease were the highest in the lower reach of the river basin,and the heavy metals such as zinc,copper,nickel,manganese and chromium were positively correlated with sucrase,catalase and urease,and negatively correlated with acid phosphatase.The dominant bacterial phyla were Proteobacteria,Actinomycetes,Acidobacteri-um and Chlorobentomycetes;in addition,heavy metals were positively correlated with Firmicutes,Bacteroides,Nitrifying Spi-rals,etc.,and Chlorella,Firmicutes,Bacteroides,and Nitrifying Spirals were in higher abundance in the areas severely pollut-ed by heavy metal.In summary,under the situation of heavy metals being in long-term high concentration had altered the soil enzyme activity,and the tolerance of Chloroflexi,Firmicutes,Bacteroidetes and Nitrospirae to heavy metal in this study area.