Ma Long, Abuduwaili Jilili, Liu Wen
State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China.
Research Center for Ecology and Environment of Central Asia, Chinese Academy of Sciences, Urumqi 830011, China.
Toxics. 2020 Sep 22;8(3):77. doi: 10.3390/toxics8030077.
Aiming at the pollution and ecological hazards of the lake sediments of Bosten Lake, once China's largest inland lake, the spatial distribution and influencing factors of the potentially-toxic elements in its surface sediments were studied with the methods of spatial autocorrelation, two-way cluster analysis, and redundancy analysis. Finally, based on the background value of potentially-toxic elements extracted from a sediment core, a comprehensive evaluation of the risk of these potentially-toxic elements was conducted with the potential-ecological-risk index and the pollution-load index. With data on the grain size, bulk-rock composition, and organic matter content, this comprehensive analysis suggested that with the enrichment of authigenic carbonate minerals, the content of potentially-toxic elements exhibited distinctive characteristics representative of arid regions with lower values than those in humid region. All potentially-toxic elements revealed a significant spatial autocorrelation, and high-value areas mainly occurred in the middle and southwest. The content of potentially-toxic elements is related to AlO3, KO, FeO, TiO, MgO, and MnO, and the storage medium of potentially-toxic elements mainly consists of small particles with a grain size <16 μm. The pollution load index (PLI) for the whole lake due to the potentially-toxic elements was 1.31, and the surface area with a PLI higher than 1 and a moderate pollution level accounted for 87.2% of the total lake area. The research conclusions have an important scientific value for future lake ecological quality assessment and lake environment governance.
针对曾是中国最大内陆湖的博斯腾湖湖泊沉积物的污染及生态危害问题，采用空间自相关、双向聚类分析和冗余分析等方法，对其表层沉积物中潜在有毒元素的空间分布及影响因素进行了研究。最后，基于从沉积物岩芯中提取的潜在有毒元素背景值，利用潜在生态风险指数和污染负荷指数对这些潜在有毒元素的风险进行了综合评估。结合粒度、块状岩石成分和有机质含量数据，该综合分析表明，随着自生碳酸盐矿物的富集，潜在有毒元素含量呈现出干旱地区的独特特征，其值低于湿润地区。所有潜在有毒元素均表现出显著的空间自相关性，高值区域主要集中在中部和西南部。潜在有毒元素的含量与AlO3、KO、FeO、TiO、MgO和MnO有关，潜在有毒元素的储存介质主要由粒径<16μm的小颗粒组成。潜在有毒元素导致的全湖污染负荷指数（PLI）为1.31，PLI大于1且污染程度为中度的区域面积占全湖面积的87.2%。研究结论对未来湖泊生态质量评估和湖泊环境治理具有重要的科学价值。
