Faculty of Sciences and Engineering, Water Resources Research Group, University of Boyacá, 150003 Tunja, Colombia.
Department of Geology and CEACTEMA, University of Jaén, Campus Las Lagunillas, 23071 Jaén, Spain.
Sci Total Environ. 2021 Mar 25;762:143113. doi: 10.1016/j.scitotenv.2020.143113. Epub 2020 Oct 20.
We studied the relationships between the trace element concentration in sediments from a saline lake at a tropical latitude (Sochagota Lake, Colombia) containing hydrothermal and anthropic inputs with the organic matter content, the mineral assemblage composition and the activity of the bacterial communities of the sediments. Organic matter-poor sediments (TOC < 0.7%) with quartz and kaolinite near the southern entrance of the lake were enriched in Zr (up to 603 mg/kg) and some major detrital elements (Na, Ti, Al and Si). Fine-sized clay-rich sediments deposited in the deep zones of the lake (central and northern segments) were characterized by substantial organic matter (up to 11.10%) and the crystallization of S-bearing minerals, clay mineral mixed layers and illite. These sediments were enriched in S, Fe, Zn, Mo, Rb, Co, K, Cr, Sb, Ni, As, Ba, Cu, Mn, Pb, P, Mg, and Sr. The presence of Fe sulfide nanoparticles enriched in heavy metals encrusting microbial cells and a dominant sulfate-reducing bacteria (SRB) community (Desulfatiglans, Desulfobacterales and Sva0485) suggested that the precipitation of the hydrothermal S and the accumulation of trace elements in the sediments was regulated by SRB activity. The crystallization of S°, barite and calcite and the good correlations between Ba, Sr and Ca indicated that previously precipitated sulfide can be oxidized by the activity of a relevant sulfur-oxidizing bacterial community (Thioalkalimicrobium, Sulfurovum, Arcobacter and Sulfurimonas), possibly facilitating the release of the metals.
我们研究了热带纬度（哥伦比亚 Sochagota 湖）盐水湖中沉积物的微量元素浓度与沉积物有机质含量、矿物组合成分和细菌群落活性之间的关系。湖泊南部入口附近富含有机质（TOC < 0.7%）且富含石英和高岭石的贫有机质沉积物富含 Zr（高达 603 mg/kg）和一些主要的碎屑元素（Na、Ti、Al 和 Si）。在湖泊深部（中部和北部）沉积的细粒富黏土沉积物的特点是有机质含量高（高达 11.10%），并且有 S -bearing 矿物、混合层黏土矿物和伊利石的结晶。这些沉积物富含 S、Fe、Zn、Mo、Rb、Co、K、Cr、Sb、Ni、As、Ba、Cu、Mn、Pb、P、Mg 和 Sr。富含重金属的 Fe 硫化物纳米颗粒包裹微生物细胞，以及优势硫酸盐还原菌（SRB）群落（脱硫杆菌目、脱硫杆菌目和 Sva0485）的存在表明，热液 S 的沉淀和痕量元素在沉积物中的积累受到 SRB 活性的调节。S°、重晶石和方解石的结晶以及 Ba、Sr 和 Ca 之间的良好相关性表明，先前沉淀的硫化物可能会被相关的硫氧化细菌群落（硫代盐单胞菌属、硫代硫杆菌属、弧菌属和硫磺单胞菌属）氧化，从而可能促进金属的释放。
