| Fluorine is a microelement which is indispensable to the human health, and the body absorbs fluorine inadequate or excessive both harm to the health. The distribution of human fluorosis in China is a wide range. Besides Shanghai, other provinces, municipalities and autonomous regions have different levels of fluorosis. In China there is more than 38 million people suffered fluorosis and about 110 million people threatened by it. Along with the development of technology, people give more and more attention to the fluorosis, and study the distribution, existing forms, transference and enrichment of fluorine in water, soil and atmosphere by micro and macro angles.This paper took Cangzhou for example, and studied the distribution of fluorine in the soil and the fluoride environmental quality of the soil. At last we studied the relationship between fluorine and golden silk jujube quality. Main results of the experiments were summarized as follows:1. The statistic characteristics of surface soil total fluorine showed that the data of the total fluorine accord with logarithm normal distribution approximately. Fluorine in three counties belonged to intermediate variability degree which reflected the influence factors are quite simple. The contents of all total fluorine in Botou County are higher than the soil (A level) fluorine background value (478mg/kg).2. The fitting results of semi-variance function model showed that the total fluorine from Xianxian and Botou were fitted by exponential model, and it was fitted by spherical mode in Cangxian. Their spatial correlation distances were 52643.1m, 54539.1m, 39355.2m respectively. The total fluoride had a strong spatial correlation in Xianxian whereas they had the moderate spatial correlation in others. The Kriging method was applied to estimate the unobserved points, and we could find that the spatial distribution of soil total fluoride were mainly affected by local hydrological effects in this area, however some areas due to the impact of human activity also showed a partial abnormality.3. The contents of surface soil total fluorine in three counties were much higher. In the 931 sampling sites, there were only 41 sites were lower than average fluorine content. However, the contents of water soluble fluorine and shallow groundwater fluoride were relatively lower. All of the water-soluble fluorine contents were not lower than 0.5mg/kg in the 52 sampling sites, and it did not cause the dental caries disease. There were only eight sites higher than 2.50 mg/kg, accounted for 15.4% of total number of samples.4. There were rich in calcium in the research region. F-and Ca2 + combine to calcium fluoride in the soil which was difficult to dissolve in water and could not harm to soil. That was why the contents total fluorine was higher, whereas water-soluble fluorine and shallow groundwater fluoride were relative lower. But the large number of fluorine brought from the depth to the surface participated in material cycle, which would change soil physical and chemical properties. Long-term irrigating fluoride groundwater would aggravated soil salinization, lead to deterioration of soil permeability, and affect crop growth. Besides, it would decrease soil adsorption capacity, and result in the groundwater pollution.5. In the 38 orchards, we found that the contents of fluorine in golden silk jujube ranged from 0.33mg/kg to 0.50mg/kg, and it did not exceed the national permissible levels of fluoride standards (0.50mg/kg).6. This paper analysed the relationship of fluorine and golden silk jujube quality. The fluorine indicators included total fluorine, water soluble fluorine and shallow groundwater fluoride. The indicators of golden silk jujube quality included single fruit weight, total soluble sugar, titratable acid and vitamin C. The results showed that, only water soluble fluorine (20～40cm) was negative correlation with total soluble sugar. The various forms of fluoride in other soil layers were not significant relationship with golden silk jujube quality.
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