矿区有机质调控铅镉重金属形态转化机制的光谱计量学研究

Heavy metal pollutants produced by mining and chemical engineering industries are highly toxic and stable in environment, posing a great threat to the ecosystem. Widespread dissolved organic matter (DOM) contains numerous chemical groups, and can react with heavy metals to form organometallic complexes, which affect the morphology, transformation, and bioavailibility of heavy metals. However, current researches on environmental interactions lack effective analytical tools with temporal and spatial resolution, molecular insight into the regulation mechanism of DOM to the form transformation of heavy metals is still unclear. In this project, regions polluted by heavy metal mining in Hunan Province are studied as the research area. By developing chemometric analytical methods such as PARAFAC analysis and two-dimensional correlation analysis for environmental spectroscopy and combining with micro-spectroscopic imaging analysis, we aim to establish a spectroscopic monitoring-chemometric analysis platform, so as to clarify the interaction mechanism between DOM and heavy metals, and further explore corresponding environmental factors that make contributions. Insights into the regulation mechanism of DOM to heavy metals can provide valid prediction for environmental behavior of heavy metal pollutants in mining, and theoretical basis for environmental remediation of heavy metal pollution.

矿山开采及化工废水排放产生的重金属污染物毒性较强，在环境中稳定存在，对生态系统构成极大威胁。广泛存在于环境中的溶解性有机质含有大量的化学基团，可与重金属离子形成有机金属复合体，进而影响后者的形态、迁移转化、生物适应性等环境行为。由于目前关于环境相互作用的研究仍缺乏有效的时空分辨分析方法，对于溶解性有机质调控重金属污染物的形态转化的分子机制仍不明朗。本项目拟以湖南省典型重金属受污矿区为研究区域，通过改进平行因子、二维相关分析等环境光谱计量分析方法，并与光谱显微成像分析创造性耦合，探索矿区溶解性有机质对Pb、Cd等重金属污染物形态转化的调控机制，并考察多种环境因子的影响。研究旨在构建光谱监测-计量分析平台，阐明矿区有机质-重金属离子的作用机理及主导影响因素，为矿区重金属污染物的环境行为提供有效预测，为重金属污染区域环境修复方案的制定提供理论依据。

矿区土壤中的有机质含有大量的化学基团，可与矿区残留的重金属污染物形成有机金属复合体，进而影响后者的形态、迁移转化、生物适应性等环境行为。目前关于矿区土壤有机质调控重金属污染物的形态转化的分子机制仍不明朗。本项目基于矿区土壤有机质特性，发展了光谱斜率DSlope240-280等紫外可见光谱新参数，结合三维荧光-平行因子分析及二维相关光谱，建立了研究土壤有机质结构及其环境行为的分子光谱计量学分析方法；通过环境光谱计量分析，确定了土壤有机质中参与重金属结合的主要官能结构及结合次序，解析了土壤有机质-重金属污染物相互作用规律；研究了pH、土壤有机质来源等因素对土壤有机质-重金属结合的影响，辨析了介导土壤有机质调控铅镉重金属污染物环境行为的关键因子。此外，基于有机质对重金属环境行为的影响，初步探索了处理含镉重金属废水的铁氧体吸附技术及处理矿山冶炼废渣的资源化-土壤化方法。项目通过构建光谱监测-计量分析平台，阐明了矿区有机质-重金属离子的作用机理及主导影响因素，成果为矿区重金属污染物的环境行为提供了有效预测，为重金属污染区域环境修复方案的制定提供了理论依据。