Simulated control of water-soluble fluoride content in tea garden soils
茶园土壤水溶性氟含量的模拟调控

Calcium-containing materials including CaCO3, CaO, Ca3(PO4)2, CaCl2 and CaSO4 were used to regulate water-soluble fluoride in tea garden soils collected from Yingshan, Dawu, Zhushan, and Chibi of Hubei province and Hangzhou of Zhejiang province. The results indicated that the content of water-soluble fluoride in soils of Yingshan, Dawu and Zhushan decreased after application of CaCl2 and CaSO4, and the effect of applying CaCl2 was better than that of CaSO4. The appropriate amount was 1~2 g · kg-1 of CaCl2 or CaSO4 in soils of Yingshan and Dawu, and 3~5 g · kg-1 of CaCl2 or CaSO4 in the soil of Zhushan. The content of water-soluble fluoride in soils of Chibi and Hangzhou decreased by applying CaCO3, CaO or Ca3(PO4)2, and the appropriate amount for the soil of Chibi was 1.5~2 g · kg-1 of CaCO3 or CaO or 3~4 g · kg-1 of Ca3(PO4)2, while for the soil of Hangzhou was 4~5 g · kg-1 of CaCO3, CaO or Ca3(PO4)2. The effect of applying CaCO3 was better than that of CaO and Ca3(PO4)2 on the soils of Chibi and Hangzhou, however, the content of water-soluble fluoride in these two soils increased after applying CaCl2 or CaSO4.