[Quality evaluation of soil fluorine on Hangjiahu Plain based on GIS]

Contents of fluorine in the plough layer (0-20 cm) of paddy soils from Hangjiahu Plain were investigated to evaluate quality of fluorine using total fluorine index method. Kriging method was applied to study the spatial variability of soil total fluorine in relation to their influential factors and their distribution maps were obtained based on GIS. The results showed that the range of total fluorine (TF) contents in the soils from central and eastern parts of Hangjiahu Plain was higher than that from the western part. The concentrations of TF in soil had a close relationship with parent material, pH value, organic matter, cation exchange capacity content and soil texture. The main range of TF was 200-300 mg/kg, while TF contents accounting for 23.7% of the area were less than 200 mg/kg in the studied area. In which TF contents in soil in Yuhang County were the lowest, less than 100 mg/kg.