Lagoons are the hotspot ecosystems whose sustainability should be secured using the ecological assessment indicators. This study aimed to quantify the surface sediment metal distributions of Çardak Lagoon in the Marmara region of Turkey, to characterize their natural and anthropogenic sources and transport mechanisms and to assess their potential ecological risks. The surface sediment samples were collected from 11 stations using Van Veen grab, while for the background values to be determined, core sampling was used from two stations. The analyses of multiple elements, total organic carbon, carbonate, and chlorophyll degradation by-products were carried out to characterize sediments. Enrichment factor and the indices of potential ecological and toxic risks were applied to assess the ecological status of the surface sediments. The operation of the gold mine in the close vicinity was found to be responsible for the enrichment of Au and Hg in the lagoon sediments. Cd, Tl, Sb, and Sr were the other elements responsible for the enrichment. The potential risk levels of the lagoon varied between the low and significant levels. The riskiest elements were found to be Hg and Cd which in turn pointed to the mining and agricultural activities as the most dominant human disturbance. The toxic risk index of Çardak Lagoon was estimated to range from 5.21 to 11.00, with a low mean value of 7.98. The C:N ratio range of 8.52 to 134.93 (a mean of 29.07) indicated that the organic C source was mostly of the terrestrial origin, in particular, from the surrounding agricultural lands.

中文翻译：

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沿人类扰动梯度的Çardak泻湖表面沉积物的生态风险评估。

泻湖是热点生态系统，应使用生态评估指标来确保其可持续性。这项研究旨在量化土耳其马尔马拉地区Çardak泻湖的表层沉积物金属分布，以表征其自然和人为来源及运输机制，并评估其潜在的生态风险。使用Van Veen抓斗从11个站采集了表面沉积物样本，而要确定背景值，则从两个站进行了岩心取样。进行了多种元素，总有机碳，碳酸盐和叶绿素降解副产物的分析以表征沉积物。利用富集因子和潜在的生态和毒性风险指数评估表层沉积物的生态状况。发现附近金矿的开采是泻湖沉积物中金和汞富集的原因。Cd，Tl，Sb和Sr是引起富集的其他元素。泻湖的潜在风险水平在低水平和高水平之间变化。发现最危险的元素是汞和镉，这反过来又表明采矿和农业活动是人类最主要的干扰。Çardak泻湖的毒性风险指数估计为5.21至11.00，均值低至7.98。C：N比值​​介于8.52至134.93（平均值为29.07）之间，表明有机碳源主要来自陆地，尤其是周围的农田。