我国南方水源低氟成因探讨

本文比较了我国东部花岗岩上各类地带性土壤中的总氟、水萃取态氟含量及各类土壤对氟离子的吸附能力。总氟含量有自北向南递减的趋势。赤红壤与砖红壤氟含量最低。水萃取态氟含量亦以赤红壤与砖红壤为最低。吸附实验表明,东部土壤对氟离子的吸附能力依次为棕壤<黄壤<红壤<砖红壤。从地球化学角度考虑,我国华南地区水源低氟的原因:①氟在风化-成土过程中已达较强烈淋溶;②氟矿物溶解度低;③土壤对水溶液中氟离子的吸附能力较强。

A Study on the Reason of the Low Flourine Content in Groundwater in Southeast China

Total flourine content and water extractable flourine content in zonal soils developed on granite from northeast China, north China, middle China and south-east China were compared, and the adsorption capacity for flourine anion of these soils were studied. The total flourine content in soils decreases from north to south, with the lowest in lateritic soil and laterite, and the water extrac-table flourine content varies in the same way. Adsorption experiment results show that in the eastern part of China, adsorption capacity of soils for flourine anion increases successively from brown soil, yellow soil to red soil and laterite. Considering from the viewpoint of geochemistry, the reason for low flourine content in water resources in south-east China lies on: (1) the heavy leaching of flourine during the process of the, weathering of granite into soils. (2) the high hydroxyl content of the soils in southeast China resulting in high exchange capacities for flourine anion.