Department of Geography, Faculty of Humanities and Letters, Ardahan University, 75002, Ardahan, Turkey.
Department of Turkish and Social Science Education, Faculty of Education, Çanakkale Onsekiz Mart University, 17100, Çanakkale, Turkey.
Environ Monit Assess. 2020 May 12;192(6):359. doi: 10.1007/s10661-020-08336-9.
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.
泻湖是热点生态系统，其可持续性应该通过生态评估指标来保障。本研究旨在量化土耳其马尔马拉地区恰尔达克泻湖的表层沉积物中金属的分布情况，以确定其自然和人为来源以及运输机制，并评估其潜在的生态风险。使用 Van Veen 抓斗从 11 个站位采集表层沉积物样品，而为了确定背景值，则从两个站位进行了岩芯采样。对多种元素、总有机碳、碳酸盐和叶绿素降解产物进行了分析，以对沉积物进行特征描述。应用富集因子和潜在生态及毒性风险指数来评估表层沉积物的生态状况。研究发现，附近金矿的开采活动导致了泻湖沉积物中 Au 和 Hg 的富集。Cd、Tl、Sb 和 Sr 等其他元素也导致了富集。泻湖的潜在风险水平在低风险和显著风险之间变化。风险最大的元素是 Hg 和 Cd，这反过来表明采矿和农业活动是最主要的人为干扰。恰尔达克泻湖的毒性风险指数估计范围为 5.21 至 11.00，平均值为 7.98。C:N 比值范围为 8.52 至 134.93（平均值为 29.07），表明有机 C 源主要来自陆地，特别是来自周围的农业用地。
