三峡库区地方性氟中毒病区与非病区土壤氟地球化学

巫山、奉节是三峡库区最典型的地方性氟中毒区（简称地氟病区）。利用多目标地球化学调查方法，通过野外实地调查，大面积系统采集土壤深层、表层土壤样品、分析测试、数理统计，探讨了三峡库区沿长江各区县土壤氟含量、典型地氟病区与非病区深层、表层土壤氟的含量特征与差异。发现三峡库区沿长江各区县深、表层土壤氟含量均表现为：巫山＞奉节＞涪陵＞丰都、万州、开县、云阳、忠县、长寿。巫山、奉节表层土壤氟含量分别为全国土壤氟含量均值的2.598倍、1.883倍，丰都等6区县深、表层土壤F含量与全国均值基本相当。各地区表层土壤明显继承了深层土壤氟的地球化学特征。地氟病最严重的巫山县表层土壤氟富集程度最高，而最轻的长寿县表层土壤则表现出明显的氟淋失。地氟病区深层、表层土壤F含量均远高于非病区，土壤F含量与地氟病发病率间具极显著正相关，土壤F含量对发病率具有明显的影响。土壤F与土壤中造岩元素具显著正相关，主要来自于成土母质。

CHARACTERISTICS OF FLUORIDE IN SOILS FROM FLUOROSIS AND NON-FLUOROSIS AREAS IN THE THREE GORGES RESERVOIR DISTRICT

Wushan and Fengjie counties are typical fluorosis areas in the three Gorges Reservoir District.In this article,the authors adopted the means of multi-object geochemistry surveying to analyze the Fluoride content in soils of each county along the Yangtze River in Three Gorges Reservoir District,and to analyze their characteristics and distinction of Fluoride in different depths of soils through comparing the fluorosis areas with normal areas.It can be concluded that the value of Fluoride content in soils of Wushan county is the highest among all the counties investigated,Fengjie county is the second,Fulin county the third,and other counties the fourth,such as Fengdu,Wanzhou,Kaixian,Yuyan,Zhongxiang and Changshou,which are similar in either top soils or deep soils.Fluoride content in soils of Wushan county is 2.598 times higher than the average of Fluoride content in the whole country of China,while the value of Fengjie county is 1.883 times higher;the others have a similar value in comparison with the national average level.The top-soil in every place has the geochemistry characteristics of fluorine observed in deep soil.Fluoride in top soil of Wushan county enriches mostly in hypergenesis,where fluorine disease is most serious.Fluoride in Changshou county is lost,where fluorine disease is unfrequent.The value of Fluoride content from different deep soils in fluorosis areas is higher than in non-fluorosis areas.The incidence of fluorosis is correlative with the content of Fluoride,which comes from mother-rock and is related to petrogenic element in soil.