SUN Rui-gang 1, 2, LI Lian-xiang 1, 2, SU Li-ming 3

1. China Institute of Water Resources and Hydropower Research, Beijing 100048, China
2. National center for Efficient Irrigation Engineering and Technology Research, Beijing 100048, China
3. Taierzhuang Water Conservancy Bureau, Shandong 277400, China

Abstract: Determining soil soluble fluoride content can control endemic fluorosis indirectly, as soil soluble fluoride is a main source of high fluoride groundwater. Pretreatment conditions play a vital role in determining soil soluble fluoride. The impact of soil water ration, soil extraction time, temperature and shaking speed, soil sieve particle size on determining soil soluble fluoride were studied in this paper. Soil samples were collected from Weinan city, Shanxi province. Results show that the soil water ration, soil extraction time, temperature and shaking speed, soil sieve particle size all have effect on the result of determining soil soluble fluoride. By comparing different treatments, the suitable pretreatment conditions for tested soil soluble fluoride in Weinan are as follows: soil water ratio is 1:10, extraction time is 50 min and can be longer for clay soil, temperature is 45℃, shaking speed is 180r/min, soil sieve particle size can be from 0.5mm to 2.5mm for sandy soil and 2.5mm for clay soil. Before soil extraction was tested, soil extraction should be filtered by 0.45μm filter paper and 0.22μm water system filter. For sandy soil, soil extraction can also be centrifuged at 8 500r/min speed and filtered by 0.22μm water system filter. This study served as a base of fluoride related research in Weinan, and played an important role in analyzing the soil fluorine pollution and assessing the surrounding areas fluorosis.

Key words: Soil soluble fluoride, high fluoride groundwater, pretreatment conditions, extraction

Published in: Journal of China Institute of Water Resources and Hydropower Research (Vol. 11 No. 1, 2013)