This study investigates surface water contamination of Ben-Kazza River in Morocco, fed by effluents from an adjacent lagoon-based wastewater treatment plant (WWTP) and seasonally by industrial effluents, and which occasionally serves to irrigate agricultural fields. This study has two purpose: i) to track the main sources of contamination through the evolution of dissolved organic matter (DOM) characteristics along the watercourse, and ii) to characterize the WWTP influents and effluents with a focus on the efficiency of the lagoon treatment. We characterized a total of 495 water samples across the watercourse and from the inlet and outlet of the WWTP, using UV–visible absorption and excitation–emission fluorescence coupled with chemometric analyses. Absorption indicators and fluorescence indices were calculated and compared across sampling points. Results highlight spatial shifts together with temporal changes in DOM. PARAFAC identified components that varied between protein-like, humic-like and anthropogenic-like fluorophores along the river, permitted to trace the anthropogenic components and their sources. The lagoon treatment appeared to better remove fresh organic material than humic material: fluorescence intensity decreased by 68 % for peak T1 and by 22 % for peak C. Maximum fluorescence intensities (Fmax) decreased across all PARAFAC components, leading to more than 55 % reduction of ΣFmax.

中文翻译：

---

确定摩洛哥河流中有机污染物的来源和分布：通过吸收、激发-发射荧光和化学计量学分析表征溶解有机物


本研究调查了摩洛哥本卡扎河的地表水污染，这些污染由邻近的泻湖污水处理厂 （WWTP） 的污水和工业污水季节性供应，偶尔用于灌溉农田。本研究有两个目的：i） 通过沿河道溶解有机物 （DOM） 特性的演变来追踪主要污染源，以及 ii） 表征污水处理厂的进水和流出物，重点是泻湖处理的效率。我们使用紫外-可见光吸收和激发-发射荧光与化学计量学分析相结合，对整个河道以及污水处理厂入口和出口的总共 495 个水样进行了表征。计算吸收指标和荧光指数，并在采样点之间进行比较。结果突出了 DOM 的空间变化和时间变化。PARAFAC 确定了沿河蛋白质样、腐殖质样和类人成荧光团之间变化的成分，允许追踪人为成分及其来源。泻湖处理似乎比腐殖质更好地去除新鲜有机物质：峰 T1 的荧光强度降低了 68%，峰 C 的荧光强度降低了 22%。所有 PARAFAC 组分的最大荧光强度 （Fmax） 均降低，导致 ΣFmax 降低 55% 以上。