Alorda-Montiel Irene, Rodellas Valentí, Arias-Ortiz Ariane, Palanques Albert, Bravo Andrea G, Rodriguez-Puig Júlia, Alorda-Kleinglass Aaron, Green-Ruiz Carlos, Diego-Feliu Marc, Masqué Pere, Gilabert Javier, Garcia-Orellana Jordi
Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain; Institut de Ciència i Tecnologia Ambientals, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Departament de Física, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Mar Pollut Bull. 2025 Nov;220:118347. doi: 10.1016/j.marpolbul.2025.118347. Epub 2025 Jul 3.
Coastal enclosed ecosystems, such as lagoons, are vulnerable to anthropogenic impacts because they favor the accumulation of contaminants from the surrounding watersheds, particularly in their sediments. Europe's largest saltwater lagoon, the Mar Menor (SE, Iberian Peninsula), is a highly impacted ecosystem and the first in the continent to be granted personhood rights. Based on a high-resolution spatial and temporal dataset, we present the historical reconstruction of metal contamination in this ecosystem during the last century. Our results highlight that sediment metal contamination has been mainly driven by the development of the mining industry in the nearby Sierra Minera de Cartagena-La Unión in the late 19th and until the mid-20th century when premeditated mining spills were forbidden. Runoff from former mining areas still transported metals to the lagoon even after mining ceased in the 1990s. The southern sector of the lagoon, closest to mining-affected ephemeral streams, is the most impacted by metal contamination and holds the highest metal stocks. Stocks since 1900 for the entire lagoon reached values of 9200, 1.6, 450, 270, 10,000, and 12 tons of Pb, Hg, As, Cu, Zn, and Ag, respectively. Maxima concentrations were reached in the mid-20th century, with values of 3400, 0.53, 100, 50, 3700, and 5.5 mg·kg for Pb, Hg, As, Cu, Zn, and Ag. Afterward, while some metals' concentrations declined, others were still supplied to the sediments through runoff from former mining areas and sources related to urban expansion. Metal concentrations reported in this study surpass sediment quality guidelines and are generally higher than those found in similar ecosystems globally. Current surface metal concentrations are lower than during most of the 20th century, and sediments seem to retain metal stocks effectively. However, climate change and eutrophication could increase the risk of metal remobilization, further impacting this already vulnerable ecosystem. This study emphasizes the need for attention to managing coastal enclosed ecosystems, where global change impacts can exacerbate the impact of legacy contamination.
沿海封闭生态系统，如泻湖，容易受到人为影响，因为它们有利于周围流域污染物的积累，尤其是在沉积物中。欧洲最大的咸水泻湖——马尔·梅诺尔（位于伊比利亚半岛东南部）是一个受到严重影响的生态系统，也是欧洲首个被赋予法人权利的生态系统。基于高分辨率的时空数据集，我们呈现了该生态系统在上个世纪金属污染的历史重建情况。我们的研究结果表明，沉积物中的金属污染主要是由19世纪末至20世纪中叶附近的卡塔赫纳 - 拉乌尼翁矿业特区采矿业的发展所驱动的，直到有预谋的采矿泄漏被禁止。即使在20世纪90年代采矿活动停止后，以前矿区的径流仍将金属输送到泻湖。泻湖最南端靠近受采矿影响的季节性溪流的区域，受金属污染影响最大，金属存量也最高。自1900年以来，整个泻湖的铅、汞、砷、铜、锌和银的存量分别达到9200吨、1.6吨、450吨、270吨、10000吨和12吨。20世纪中叶达到了最高浓度，铅、汞、砷、铜、锌和银的浓度分别为3400毫克/千克、0.53毫克/千克、100毫克/千克、50毫克/千克、3700毫克/千克和5.5毫克/千克。此后，虽然一些金属的浓度下降，但其他金属仍通过以前矿区的径流和与城市扩张相关的来源供应到沉积物中。本研究报告的金属浓度超过了沉积物质量指南，并且总体上高于全球类似生态系统中的浓度。当前的表层金属浓度低于20世纪的大部分时间，沉积物似乎有效地保留了金属存量。然而，气候变化和富营养化可能会增加金属重新活化的风险，进一步影响这个本已脆弱的生态系统。这项研究强调了关注沿海封闭生态系统管理的必要性，在这些地方，全球变化的影响可能会加剧遗留污染的影响。
