陕西省大荔县地下水中氟的含量特征及其影响因素分析

大荔县为地方性氟中毒病高发区，主要因长期饮用氟含量高的地下水所致。通过分析大荔县269件地下水样品中氟含量，查明地下水氟含量为0．01～11．8mg／L，均值为1．91mg／L，氟含量高于1．0mg／L的水样样本达70．6％。调查分析发现，大荔县地下水氟含量在空间分布上具有北高南低的特征，富集最严重的区域出现在渭河二、三级阶地的东端，高氟地下水区域占到全区总面积的63％。大荔县丰富的氟源、特定的地形地貌、干燥的气候环境以及缓慢的地下水力更替过程是造成地下水中氟富集的主要因素。

Analysis of the Content of Fluorin and Its Effect Fators on Ground Water in Dali County,Shannxi Province

Dali county is the high incidence area of fluorin illness, mainly because of drinking ground water with high concentration of fluorin in a long time. The content range of fluorin in ground water is 0. 01- 11.8mg/L based on the analysis of ground water samples in Dali county. The distributing character of fluorin in ground water is higher at north than that at south. The most fluorin-enriched areas are distributed in east of second and third terraces in Wei river, with the high-fluorin area accounting for 63 % of the total area. The main factors for enrichment of fluorin are the abundant sources of fluorin, the specific landform and physiognomy, the dry climate, and the slow exchanging process of ground water.