基于双金属稳定同位素体系（Cu-Pb）的河流沉积物重金属污染源解析及不确定性研究

River sediment heavy metal source apportionment is using quantitative methods to accurately identify natural and anthropogenic sources and apportion their contributions, and is the forefront of heavy metal contamination diagnoses research at present. The results can be direct serviced for regional pollution control policy making. Isotope tracing technique is a general approach for source apportionment with advantages of clear, simple and reliable. However, due to the complexity of aquatic environment system, as well as the limitations of single isotope tracer technique, the adaptabilities, accuracies and uncertainties of multi-element isotope system tracing technique for source apportionment of heavy metals in aquatic environment are worthy of to further study. On this occasion, this study plan to select the sediment heavy metal of Dexing as the study object to carry out a research of source apportionment and uncertainty of heavy metals in the river sediments based on dual stable isotope system (Cu-Pb), aim at major ecological and environmental problems caused by heavy metal pollution in water bodies, and focused on the application value of non-traditional metal stable isotope in the field of pollution source analysis. The objectives of this study are to illuminate the mechanism in source apportionment of sediment heavy metal based on multi-element isotope combination, and reveal the key factor of source apportionment uncertainty in multi-element isotope combination approach. The study work will enrich theories on metal stable isotope environmental geochemistry, and will be provide important scientific basis for prevention and control measures of heavy metal pollution in watershed.

河流沉积物重金属污染源解析是对沉积物中重金属的来源进行定性识别和定量估算，其结果可以直接服务于水体污染防治决策的制定，是当前重金属污染成因诊断研究的前沿课题。同位素示踪技术是一类较为通用的源解析手段，具有机理明确、方法简单、结果可靠等优点。然而，鉴于沉积物重金属污染来源的复杂性，以及单一同位素示踪技术的局限性，多元素同位素体系示踪技术应用于水体重金属污染源解析的适宜性、可靠性及不确定性值得深入研究。基于此，针对水体重金属污染引发的重大生态与环境问题，以我国典型矿业城市水体沉积物为研究对象，突出非传统金属稳定同位素在污染源解析领域的应用价值，开展基于双金属稳定同位素体系（Cu-Pb）的河流沉积物重金属污染源解析及不确定性研究，旨在深刻认识不同稳定同位素联合示踪重金属污染源的机制，进一步丰富金属稳定同位素环境地球化学研究，为制定流域水污染综合治理方案提供科技支撑。

河流沉积物重金属污染源解析是对沉积物中重金属的来源进行定性识别和定量估算，其结果可以直接服务于水体污染防治决策的制定，是当前重金属污染成因诊断研究的前沿课题。同位素示踪技术是一类较为通用的源解析手段，具有机理明确、方法简单、结果可靠等优点。然而，鉴于沉积物重金属污染来源的复杂性，以及单一同位素示踪技术的局限性，多元素同位素体系示踪技术应用于水体重金属污染源解析的适宜性、可靠性及不确定性值得深入研究。基于此，针对水体重金属污染引发的重大生态与环境问题，以我国典型矿业城市德兴市水体沉积物为研究对象，突出非传统金属稳定同位素在污染源解析领域的应用价值，开展基于双金属稳定同位素体系（Cu-Pb）的河流沉积物重金属污染源解析及不确定性研究。本研究主要成果包括（1）构建了基于双金属稳定同位素体系（Cu-Pb）的源解析模型，拓展了双金属示踪体系在环境重金属溯源应用研究；（2）构建了德兴地区重金属污染源谱，为矿区周边土壤/沉积物重金属源解析提供重要的参考依据，为德兴铜矿周边环境修复提供基础数据；（3）提出受体源解析模型不确定性研究方法体系。本项目研究成果推动深刻认识不同稳定同位素联合示踪重金属污染源的机制，进一步丰富金属稳定同位素环境地球化学研究，为制定德兴市流域水污染综合治理方案提供科技支撑。