中文摘要：

西藏羊八井地热电厂产生的高氟废水直接排入了流经羊八井热田的藏布曲（河）。利用离子色谱仪（IC）测定了藏布曲水样的氟浓度；通过浸提实验提取了藏布曲河床沉积物中的总氟和各种存在形态的氟，并确定了其含量。藏布曲河水的氟浓度明显受到地热废水排放的影响，河床沉积物中水溶态氟和可交换态氟的分布也与地热电厂排污口的位置有明显的对应关系。然而，河床沉积物中的铁锰结合态氟、有机束缚态氟、残余态氟和总氟的分布与地热废水排放无显著联系，表明地热废水来源氟在进入藏布曲后主要向河床沉积物中的水溶态氟和可交换态氟转化。藏布曲河床沉积物是地热废水来源氟的一个汇。

英文摘要：

The high-fluoride wastewaters generated by the Yangbajing geothermal power plant in Tibet, Which were discharged directly into the Zangbo River that flows across the Yangbajing geothermal field. The fluoride concentrations of all water samples collected from the Zangbo River were determined using ion chromatograph （ IC）, and the total fluoride （Total-F）, water soluble fluoride, exchangeable fluoride, fluoride bound to Fe/Mn oxides, fluoride bound to organic matter and residual fluoride in all riverbed sediment samples were extracted with sequential chemical extraction procedure and then their concentrations were measured. The fluoride concentration in the Zangbo River water was evidently affected by the geothermal wastewater discharge. The distribution of water soluble fluoride and exchangeable fluoride in the riverbed sediments matches well with the locations of geothermal wastewater outlets. However, there is no obvious correspondence between the locations of the wastewater outlets and the concentrations of fluoride bound to Fe/Mn oxides, fluoride bound to organic matter, residual fluoride and total fluoride in riverbed sediments, indicating that the fluoride with geothermal wastewater source was mainly transformed into water soluble fluoride and exchangeable fluoride in sediments after it was discharged into the Zangbo River. The riverbed sediment is a sink of fluoride from geothermal wastewater.