Huang Zhenyu, Liu Yi, Dai Heng, Gui Dongwei, Hu Bill X, Zhang Jin
Department of Ecology and Institute of Hydrobiology, College of Life Science and Technology, Jinan University, 510632, Guangzhou, China.
State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, 830011, Urumqi, China.
Environ Res. 2022 Mar;204(Pt D):112401. doi: 10.1016/j.envres.2021.112401. Epub 2021 Nov 18.
Oases environments in oases to be sensitive to anthropogenic activity because of ecological fragility. Polycyclic aromatic hydrocarbon (PAH) pollution resulting from anthropogenic activity leads to ecological degradation in oases. To examine the impact of anthropogenic activity on the oasis ecological environment, the present study focused on the spatial distribution and source apportionment of soil PAHs and bacterial community responses in typical oases in Xinjiang, China. The results showed that the soil PAH level were higher in the city centres of Urumqi (9-6340 μg kg), Aksu (8-957 μg kg) and Korla (8-1103 μg kg) and lower in the centres of Hotan city (11-268 μg kg) and Qira county (7-163 μg kg). Source apportionment suggested that gasoline emissions, diesel emissions, vehicle emissions, coal combustion, coke processing and biomass burning were the sources of soil PAHs. The integrated lifetime cancer risks of soil PAH exceeding the guideline safety values (10) recommended by United States Environmental Protection Agency. The ingestion and dermal exposure pathways caused the greatest health risk (contribution ≤82%). Additionally, in the soil with low PAH concentrations, the richness and evenness of the soil bacterial community were great, and the molecular ecological network (MEN) structure was complex. Among populations, Proteobacteria and Actinobacteria (relative abundance ≥17%) are the main dominant species in the bacterial communities and the keystone species in the MEN.
由于生态脆弱性，绿洲环境对人为活动敏感。人为活动导致的多环芳烃（PAH）污染会致使绿洲生态退化。为探究人为活动对绿洲生态环境的影响，本研究聚焦于中国新疆典型绿洲土壤中PAHs的空间分布、源解析以及细菌群落响应。结果表明，乌鲁木齐市（9 - 6340μg/kg）、阿克苏市（8 - 957μg/kg）和库尔勒市（8 - 1103μg/kg）市中心的土壤PAH水平较高，而和田市（11 - 268μg/kg）中心和策勒县（7 - 163μg/kg）的土壤PAH水平较低。源解析表明，汽油排放、柴油排放、车辆排放、煤炭燃烧、焦炭加工和生物质燃烧是土壤PAHs的来源。土壤PAH的综合终生癌症风险超过了美国环境保护局推荐的安全指导值（10）。经口摄入和皮肤接触途径造成的健康风险最大（贡献率≤82%）。此外，在PAH浓度较低的土壤中，土壤细菌群落的丰富度和均匀度较高，分子生态网络（MEN）结构复杂。在种群中，变形菌门和放线菌门（相对丰度≥17%）是细菌群落中的主要优势物种以及MEN中的关键物种。
