State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, China.
State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, 430074, China.
Environ Pollut. 2022 Aug 1;306:119358. doi: 10.1016/j.envpol.2022.119358. Epub 2022 Apr 27.
The Wang Lake Wetland is a highly valued area that is protected due to its high biodiversity. The wetland has a complicated hydrological regime and is subject to frequent human disturbance. We hypothesize that fluctuating hydrology and human activities have varied contributions to the temporal and spatial variations of polycyclic aromatic hydrocarbons (PAHs) in the wetland. Soil (SS), sediment (SD), and water, to acquire dissolved phase (DP) and suspended particulate matter (SPM), samples were collected from eight locations during low- and high-flow periods to elucidate multimedia phase distribution and transport of PAHs. Following the onset of the rainy season, the concentration of SPM-associated PAHs increased significantly, while the DP PAHs remained stable. Individual PAH ratios showed that, although pyrogenic sources are common, petrogenic derived compounds are the main source of PAHs in the Wang Lake Wetland. During the high-flow period, the empirical values for logarithms of the organic carbon-normalized partition coefficients (log K) of individual PAH-congeners were lower than the corresponding field-observed log K values from the SPM-DP and SD-DP systems, reflecting the complexity in evaluating multi-phase PAH partitioning. During the high-flow period, temperature-driven changes may have changed the sediment from a sink to a source for some high molecular weight PAHs. It was determined that human activities governed the PAH loading in the low-flow period, whereas during high-flow conditions, increased rainfall, higher temperatures, and fishery activity are the main factors controlling PAH input to the Wang Lake Wetland.
望江湖湿地是一个高度重视的地区，由于其生物多样性而受到保护。该湿地具有复杂的水文状况，并经常受到人类的干扰。我们假设波动的水文学和人类活动对湿地中多环芳烃（PAHs）的时间和空间变化有不同的贡献。为了阐明 PAHs 在多介质中的分布和迁移，在低流量和高流量期间从八个地点采集了土壤（SS）、沉积物（SD）和水，以获取溶解相（DP）和悬浮颗粒物（SPM）样品。在雨季开始后，SPM 相关 PAHs 的浓度显著增加，而 DP-PAHs 保持稳定。个别 PAH 比值表明，尽管热成因来源很常见，但石油衍生化合物是望江湖湿地 PAHs 的主要来源。在高流量期间，个别 PAH 同系物的有机碳归一化分配系数（log K）的对数的经验值低于 SPM-DP 和 SD-DP 系统中相应的现场观察到的 log K 值，反映了评估多相 PAH 分配的复杂性。在高流量期间，温度驱动的变化可能使一些高分子量 PAHs 从沉积物的汇转变为源。研究结果表明，在低流量期，人为活动控制了 PAH 的负荷，而在高流量条件下，增加的降雨量、更高的温度和渔业活动是控制 PAH 输入望江湖湿地的主要因素。
