南方土壤酸沉降敏感性研究Ⅲ.Si释放与缓冲作用  

Study on soil sensitivity to acid deposition in South China Ⅲ.releasing and buffering reaction of Si.

作　　者：吴箐[1] 仇荣亮[1] 杨平[1] 岑慧贤 

机构地区：[1]中山大学环境科学系

出　　处：《中国环境科学》1998年第4期302-305,共4页China Environmental Science

基　　金：国家自然科学基金;广东省自然科学基金

摘　　要：研究了模拟酸雨淋溶过程中南方主要土壤硅释放量与缓冲机理。结果表明，土壤中存在两个缓冲体系，ｐＨ值高于３．０时，土壤以初级缓冲体系为主；ｐＨ值低于３．０，尤其是离子淋溶量高于或接近ＣＥＣ值后，次级缓冲体系成为主要的质子缓冲源。淋溶液ｐＨ值的降低可加速矿物风化和Ｓｉ的释放，从而促进土壤中Ｓｉ的淋溶，但Ｓｉ的淋溶同时受到吸附、沉淀与转化过程及土壤初始条件的影响。This paper deals with the pH value of leaching solutions and the characteristics of Si releasing under the treatment of Simulated Acid Rain(SAR) in main soil types collected from South China. The results show that two proton buffering systems exist simutaneously in the soils. When the pH value of SAR is higher than 3.0, the main proton buffering reaction is attributed to the cation exchange induced by the preliminary buffering system in soils. While the pH value of SAR is lower than 3.0, especially the amounts of base cations leached from soils exceed the cation exchange capacity, the secondary buffering system plays a great role in the proton buffering reaction. The lower the pH value of SAR, the rapider the weathering of soil minerals and the more the amounts of Si leached from soils. This paper also confirms that the releasing of Si is decided not only by the weathering of soil minerals, but also by other processes, namely absorption reaction, precipitation and translocation reactions etc. which was affected by soil solid components and original conditions.

关 键 词：酸雨 土壤 敏感性 硅释放 土壤污染 土壤评价 

分 类 号：X530.2[环境科学与工程—环境工程] X825