School of Environmental Studies & State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430078, China.
School of Environmental Studies & State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430078, China; Key Laboratory of Karst Ecosystem and Treatment of Rocky Desertification, Ministry of Natural Resources, IRCK by UNESCO, Guilin, 541004, China.
Environ Pollut. 2021 Dec 15;291:118173. doi: 10.1016/j.envpol.2021.118173. Epub 2021 Sep 14.
The sedimentary history of polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) over the past 140 years in a lake sediment core from Huixian karst wetland was reconstructed. The total PAHs and OCPs concentrations ranged from 40.0 to 210 ng g and 0.98 to 31.4 ng g, respectively. The vertical distribution of PAHs and OCPs in different stages was great consistent with the history of regional socio-economic development and the usage of OCPs. As the indicators of socio-economic development, gross domestic product (GDP), population, energy consumption, highway mileage, and private vehicles correlated with the PAHs concentrations, indicating the impact of human activities on PAHs levels. The PAHs and OCPs concentrations were also affected by environmental changes in the wetland, as reconstructed by total organic carbon (TOC), sand, silt, clay, quartz, and calcite in sediments. Redundancy analysis (RDA) results showed TOC was the dominant factor to explain the concentrations of PAHs and OCPs with the explanation of 86.7% and 43.5%, respectively. In addition, TOC content had significantly positive correlation with PAHs (0.96, p < 0.01) and OCPs (0.78, p < 0.01). In particular, the significantly positive correlation (p < 0.05) between calcite and PAHs and OCPs inferred that karstification might play an important role in the migration of PAHs and OCPs in the karst area. Therefore, the lake in Huixian wetland tended to be a sink more than a source of PAHs and OCPs influenced by the increasing TOC content and karstification under climate warming.
从辉县岩溶湿地的湖泊沉积岩芯中重建了过去 140 年来多环芳烃（PAHs）和有机氯农药（OCPs）的沉积历史。总 PAHs 和 OCPs 浓度范围分别为 40.0 至 210ng/g 和 0.98 至 31.4ng/g。不同阶段 PAHs 和 OCPs 的垂直分布与区域社会经济发展和 OCPs 使用历史高度一致。作为社会经济发展的指标，国内生产总值（GDP）、人口、能源消耗、公路里程和私家车与 PAHs 浓度相关，表明人类活动对 PAHs 水平的影响。PAHs 和 OCPs 的浓度也受到湿地环境变化的影响，这些变化通过沉积物中的总有机碳（TOC）、砂、粉砂、粘土、石英和方解石来重建。冗余分析（RDA）结果表明，TOC 是解释 PAHs 和 OCPs 浓度的主要因素，分别解释了 86.7%和 43.5%。此外，TOC 含量与 PAHs（0.96，p<0.01）和 OCPs（0.78，p<0.01）呈显著正相关。特别是方解石与 PAHs 和 OCPs 之间的显著正相关（p<0.05）表明岩溶作用可能在岩溶地区 PAHs 和 OCPs 的迁移中发挥重要作用。因此，在气候变暖下，受 TOC 含量增加和岩溶作用的影响，辉县湿地的湖泊更倾向于成为 PAHs 和 OCPs 的汇而不是源。
