Facultés des Sciences, Université Ibn Tofail, Kenitra, Morocco.
Centre National de l'Energie, des Sciences et des Techniques Nucléaire, B.P. 1382 RP 10001, Rabat, Morocco.
J Environ Radioact. 2021 Feb;227:106464. doi: 10.1016/j.jenvrad.2020.106464. Epub 2020 Nov 21.
The Sidi Moussa lagoon, located in western coastal Morocco and ranked as a wetland of biological and ecological importance (Ramsar site), is contaminated due to its proximity to the industrial phosphate plants and other anthropogenic activities around it. This study was carried out to assess the current environmental state of the lagoon as well as historical inputs of pollutants over several decades. Three sediment cores were collected and analyzed for the determination radionuclide activities (Pb, Ra, U and Cs) by gamma spectrometry and element concentrations by Inductively Coupled Plasma - Mass Spectrometry. Age-depth relationships were established in two cores using Pb and Cs as chronometer and time-marker, respectively, and Constant Rate of Supply as radiometric dating model. Pb and U were present in sediment in activities much higher than those reported for non-contaminated coastal systems. Sediment accumulation rates showed a slight increase over time with a depth-averaged value of 0.16 g cm y. Enrichment Factors and practically derived sediment quality guidelines were used to assess sediment contamination/pollution and toxicological effects linked with the measured concentrations of sediment-bound elements. The profiles of Cr, Co, Cu, As and Ni displayed maximums at depths matching the start of the phosphate industrial plants, and decreasing concentrations in the sections above the maximums, revealing the positive effects of the environmental management system adopted by the phosphate company since early 2000s.
位于摩洛哥西部沿海的锡迪穆萨泻湖是一个具有生物和生态重要性的湿地（拉姆萨尔湿地），由于其紧邻工业磷矿厂和周围的其他人为活动，受到了污染。本研究旨在评估该泻湖的当前环境状况以及过去几十年中污染物的历史输入情况。采集了三个沉积物岩芯进行分析，通过伽马能谱法测定了放射性核素（Pb、Ra、U 和 Cs）的活度，通过电感耦合等离子体质谱法测定了元素浓度。使用 Pb 和 Cs 作为定年指标和时间标记，以及恒定供给率作为放射性测年模型，在两个岩芯中建立了年龄-深度关系。Pb 和 U 的活度明显高于非污染沿海系统的报道值。沉积物积累速率随时间略有增加，平均深度为 0.16 g cm y。富集因子和实际推导的沉积物质量准则用于评估与测量的沉积物结合元素浓度相关的沉积物污染/污染和毒理学效应。Cr、Co、Cu、As 和 Ni 的剖面在与磷矿工业厂开始时相对应的深度处出现最大值，而在最大值以上的部分浓度降低，这表明自 21 世纪初以来，磷矿公司采用的环境管理系统产生了积极影响。
