微生物参与下高氟区沉积物中氟的迁移行为

氟是自然界广泛分布的非金属元素，也是人体必须的微量元素之一。环境微生物作为自然界中物质迁移的主动力之一，积极地参与着多种元素的水文生物地球化学循环。研究微生物参与下沉积物中氟的释出行为，对深入理解环境氟迁移行为具有重要意义。以山西运城高氟区沉积物样品为代表，采用野外沉积物调查采集、室内环境地球化学分析和微宇宙培养实验等研究手段，从环境生物地球化学作用的角度探讨了微生物介导下沉积物中氟的迁移释出行为。研究证明，高氟区沉积物总氟质量分数介于206.2~781.0 mg/kg之间，主要含氟矿物为长石、云母、方解石、绿泥石、角闪石等。培养条件下，溶液中的氟质量浓度与微生物生长曲线呈现良好的一致性；在培养初期，溶液中的氟质量浓度迅速上升，而后逐渐缓和，14 d后呈下降趋势。其中，黏土类沉积物的释氟量较大，砂土类沉积物释氟量较小。有、无碳源对照培养说明，沉积物中一定量的碳源可被微生物代谢利用，但碳源不是影响微生物在此环境中作用的主要因素。研究证明，原生微生物代谢活动可以显著促进沉积物中氟的迁移释出，微生物作用下不同岩性沉积物中氟的释出特征也有显著的差异，本研究工作有助于进一步丰富环境氟循环的理论认识。 

Mobilization of fluoride in sediments at high fluoride area enhanced by microorganisms

As one of the most widely distributed element in nature, fluorineis essential for human body health. Microbes play a key role in the biogeochemical cycle of various elements in natural environment. This study focus on the mobilization of fluorine from sediment mediated by microorganism activities, using samples from Yuncheng Basin, Shanxi Province, an area with high fluorine-content groundwater. Our study suggest that fluoride content in sediments range between 206.2-781.0 mg/kg with feldspar, mica, calcite, chlorite and amphibole as the major fluoride bearing minerals. The fluorine concentration in the culturesolution showed a good consistency with the growth curve of microorganisms.The fluorine concentration increased rapidly at the early stage of culture, then gradually eased, and showed a downward trend after 14 days.Among them, clay type sediments release more fluoride than sand type sediments.These results indicate that the metabolic activities of the native microorganisms can significantly promote the release of fluorine from sediments. It is also observed that the release characteristics of fluorine is lithology dependent.The research of this paper will be helpful for the full understand of the cycle of fluorine in natural environment.