Spatial Distribution Characteristics and Impact Factors of Watersoluble Fluorine in Agricultural Soils——A Case Study of Jingzhou City,Hubei Province

Fluorine is one of the necessary elements to human being,while excessive uptake of the fluorine would have impact on human being health.In this study,177 typical agricultural soil samples from Jinzhou City,Hubei Province were analyzed to figure out the distribution characteristics of water-soluble fluorine content in agricultural soil in this area.Results showed that the water-soluble fluorine content varied from 0.22 mg/kg to 4.57 mg/kg among various districts,with average about 1.74 mg/kg with a variation coefficient of 50%.Water-soluble fluorine content is the highest in alluvial soil(1.86 mg/kg), followed by the paddy soi(l1.76 mg/kg),and brown-red soi(l0.55 mg/kg)water-soluble fluorine content is in the minimum. In addition,there was significantly positive correlation between water-soluble fluoride and soil pH when soil pH was less than 7.5.Water-soluble fluoride content increased significantly with organic matter for soils at uplands,while there was non-significant relationship between water-soluble fluoride content and soil pH,which indicated that high fluoride content in soil parent materials in the region with the parent from alluvial formation contributed primarily to the big vitiations in soil water-soluble fluoride content.