长江经济带某石化场地土壤中污染物分布与微生物特征

从长江经济带某在役石化场地采集了3个点位不同深度的土壤样品,测定了石油烃等污染物的含量和微生物的群落结构,以揭示污染物分布规律和微生物特征。结果显示,3个点位污染程度不同,但污染物含量均随深度先升高后降低,最高含量均出现在埋深4.0 m左右,即地下水位附近。土壤中C6-C9高达5 302 mg/kg,C10-C40高达625.6 mg/kg,芳烃高达455.2 mg/kg,卤代烃高达41.54 mg/kg。土壤微生物的丰富度和多样性随深度增加而降低,同一深度土壤微生物的丰富度和多样性随污染物含量增大而降低。门水平上Actinobacteria、Firmicutes和Spirochaetes的相对丰度和石油烃含量显著正相关(p<0.05),属水平上Streptomyces、SCADC1-2-3、Desulfitobacterium和Cryptanaerobacter的相对丰度和石油烃含量显著正相关(p<0.05)。

Pollutant distribution and microbial characteristics at a petrochemical site in the Yangtze River Economic Belt

Soils at different depths were collected from three sampling points in an in-service petrochemical site in the Yangtze River Economic Belt. Thereafter, the concentration of petroleum hydrocarbons and the microbial community structure in the samples were measured to reveal the pollutant distribution and microbial characteristics. The overall pollution degree of the three points was found to differ; however, the pollutant concentration first increased and then decreased with depth in all cases, with the highest concentration found at the depth of approximately 4.0 m (i.e., near the groundwater level). C6-C9 up to 5302 mg/kg, C10-C40 up to 625.6 mg/kg, aromatic hydrocarbon up to 455.2 mg/kg, and halogenated hydrocarbons up to 41.54 mg/kg were detected in the soils. The richness and diversity of soil microorganisms were found to decrease with an increase in soil depth, and at the same depth, the richness and diversity of the soil microorganisms decreased with an increase in soil pollutant concentration. At the phylum level, the relative abundances of Actinobacteria, Firmicutes, and Spirochaetes were significantly positively correlated with the concentration of petroleum hydrocarbon (p<0.05). Further, at the genus level, the relative abundances of Streptomyces, SCADC1-2-3, Desulfitobacterium, and Cryptanaerobacter were significantly positively correlated with the concentration of petroleum hydrocarbon (p<0.05).