南方土壤酸沉降敏感性研究 Ⅴ.模拟酸雨条件下土壤矿物风化特征

Study of Sensitivity of Soil to Acid Deposition in South ChinaⅤ.Weathering Characteristics of Soil Minerals under Simulated Acid Rain

研究了模拟酸雨条件下土壤及粘土矿物与砂矿物的风化特征．结果表明，在本实验时间范围内，ｐＨ＜３．５的模拟酸雨可引起土壤矿物风化速率的明显增大，土壤矿物风化速率的变化特点是先快后慢．不同土壤类型的风化速率取决于发育程度和易风化矿物的质量分数．发育程度较低的土壤，盐基离子的释放主要来源于砂矿物组，而发育程度较高的土壤，盐基离子则主要来源于粘土矿物组．

The weathering characteristics of soil clay minerals and soil sand minerals under simulated acid rain are studied in this paper. The results show that the weathering rates increase evidently only when the pH value of simulated acid rain is below 35 during the experimental time. The weathering rates,which decrease with time, depend not only on the genetical degree of soils but on the contents of easily weatherable minerals. The base cations are mainly from sand minerals in soils with low genetical degree while from clay minerals in soils with high genetical degree. 