红壤中质子化及铝的溶解与质子缓冲之间的关系

 用平衡实验及动力学实验研究了我国南方4种红壤的表面质子化及铝的溶解与质子缓冲之间的关系.结果表明,由于游离氧化铁的含量、活性及对铝溶解反应位的掩盖程度等与质子化密切相关因素的不同影响,4种红壤的总H⁺消耗量和铝溶解量不同,宁海红壤和嵊县红壤的质子化程度及H⁺的总消耗量大于永春红壤和屯溪红壤;屯溪红壤铝的溶解量最大,宁海红壤铝的溶解量最小.尽管屯溪红壤铝的溶解量最大,但H⁺的总消耗量却最小.当红壤中氧化铁含量较高时,铝的溶解在H⁺消耗中只起次要作用,质子化过程是H⁺消耗的主要途径.

The relationship of protonation and dissolution of aluminum with proton buffering in red soils

Both batch and kinetics experiments were conducted to study the relationship of protonation and dissolution of Al with proton buffering in 4 red soils of south China. Results show that the main cause is various influence of factors such as the contents and activity of free Fe oxides, the extent of Al dissolution reaction sites coated by Fe oxides film, which are closely related to protonation. The total amounts of H+ consumption and Al dissolution are different. Both the extent of protonation and the amount of H+ consumption of Ninghai red soil and Shengxian red soil are higher than those of Yongchun red soil and Tunxi red soil. The amount of dissolved Al of Tunxi red soil is the highest; while that of Ninghai red soil is the lowest. However, the total amount of H+ consumption of Tunxi red soil is the lowest. Under the condition of relatively high content of Fe oxides in red soil, protonation may play an overwhelming role in H+ consumption, whereas Al dissolution may play only a minor role.