土壤pH对茶园土壤有效氟含量的影响

以茶园土壤为对象,通过室内模拟培养和田间改良试验,研究了茶园土壤pH对土壤中水溶态氟和交换态氟含量的影响.结果表明,在模拟培养下,当土壤pH由4.0降至3.5时,土壤水溶态氟含量迅速升高,当pH值在4.0~5.0之间时,水溶态氟含量较为稳定,之后随着土壤pH升高水溶态氟含量增加;交换态氟含量的变化趋势与之大致相反,且pH对20~40 cm土层土壤有效氟的影响比0~20 cm土层显著,对水溶态氟的影响比交换态显著,在强酸性土壤条件下对有效氟含量的影响比酸性条件下显著.田间试验结果与之基本一致,以pH 5.0为基点,随土壤pH值的上升或下降,两层土壤水溶态氟含量均增加,其中pH值降低对土壤水溶态氟的影响更大.

Influence of soil pH on available fluoride content of the soil in tea garden

Laboratory incubation tests and a field experiment were conducted to study the influence of soil pH on water soluble fluoride and exchangeable fluoride contents in tea garden soil. The results showed that the soil water soluble fluorine content increased obviously as soil pH value decreased from 4.0 to 3.5; it changed slightly at the ranging from pH 4.0 to pH 4.5, and then it increased with the raise of pH value. The change trend of soil exchangeable fluoride content was opposite. Soil pH had more influence on water soluble fluoride than on exchangeable fluoride, and the influence on available fluoride was more in 20-40 cm soil layer than in 0-20 cm soil layer, greater in strong acidic soil than in acidic soil. The field experiment also showed that pH 5.0 was the lowest point of soil water soluble fluoride content in the range of pH 4.5-6.0, and water soluble fluoride contents in two soil layers increased as soil pH value rose or fell from 5.0. Soil acidification could lead to water soluble fluoride content dramatic increasing.