摘要
研究了模拟酸雨对我国南方主要土壤类型盐基离子淋溶的影响，结果表明，ｐＨ低于３．０或３．５时，盐基离子淋溶总量明显增加，但ｐＨ高于３．５时，则影响不明显．相对于二价Ｃａ２＋、Ｍｇ２＋，Ｋ＋、Ｎａ＋淋溶释放受模拟酸雨影响不大．在不同模拟ｐＨ阶段，土壤可能由于不同的缓冲与反应机制而导致盐基释放．ｐＨ高于３．５时，以溶解淋溶为主，ｐＨ＝３．５时，以离子交换反应为主，ｐＨ低于３．５时，阴离子吸附、矿物风化及粘土的铝边缘和铝氧化物的溶解均可能对土壤离子释放造成影响．
Acidic deposition is considered an environmental problem that may affect the soil's cation exchange status.This study used column leaching experiments to examine the influences of simulated acid rain with different pH values on base cation leaching of main soil types collected from South China.The results showed that amounts of leaching base cations increased obviously when the pH value of simulated acidic rain was lower than 3.0 or 3.5,while the amounts almost did not differ when pH higher than 3 5. The leaching of Ca 2+ and Mg 2+ was affected evidently by the pH value of simulated acidic rain,compared with the leaching of K + and Na +.The H + buffering mechanisms which may vary in different simulated pH acidic rain are proposed for main soils studied.The dissolving reaction of salts was the dominant resources of leaching base cations and H + buffering when pH value higher than 3.5. The mechanisms of H + buffering treated with acid rain at pH 3.5 were the exchangeable cations and sulfate sorption. Dissolved aluminum on the broken edge of clay and aluminum oxides weathering of original and secondary minerals and sorption of sulfate played a grea role on the leaching of soil cations and H + buffering when the soils treated with acid rain of pH lower than 3.5.
出处
《环境科学》
EI
CAS
CSSCI
CSCD
北大核心
1997年第5期23-27,共5页
Environmental Science
基金
国家自然科学基金
关键词
酸雨
盐基离子
淋溶
土壤敏感性
simulated rain,base cations,leaching,soil sensitivity.
