模拟酸雨对三峡库区灰棕紫泥酸化的影响

Influences of Simulated Acid Rain on the Acidification of Grey-brown Purplish Soil from the Three Gorges Reservoir Region

采用模拟酸雨淋溶实验,研究了不同pH值条件下模拟酸雨对三峡库区灰棕紫泥酸化的影响。结果表明,酸雨pH值越低对土壤酸化影响越严重;不同酸雨淋溶经不同层次土体的收集淋出液的电导都呈现先升后降的趋势,而淋出液的pH值却显示出先降后升的变化趋势;土壤pH值和CEC含量越高,淋滤液的电导率越大;土壤盐基离子的淋失量随模拟酸雨pH值的降低而增加,而土壤铝的淋溶量随酸雨pH值下降而上升。经不同的酸雨淋洗后,对不同层次土体进行理化性质分析,均出现了不同程度的变化。

Column leaching tests were performed to probe the effect of simulated acid rain at different pH values on the acidification of grey-brown purplish soil from the Three Gorges Reservoir Region. The results indicated that the lower the acid rain pH value the more serious the acidification of the soil; the electric conductance of the solution leaching through different soil layers increased at first, then decreased, while the pH value of leachate changed reversely. In general, the higher the pH value and CEC content of the soil were, the greater the electric conductivity of the leachate was. The releasing amount of base ions in four types of typical soils increased with increasing rain acidity, while the leaching amount of aluminium in four types of typical soils increased with the decline of acid rain pH. Changes in the physical and chemical properties of respective soil layers to different degrees were detected after the addition of simulated acid rain of different pH values.