南方酸性森林土壤中铝活化过程参数化模型的建立与验证  

A PARAMETERIZED MODEL FOR ALUMINUM MOBILIZATION IN ACIDIC FOREST SOILS OF SOUTHERN CHINA

作　　者：钱诚[1] 张逸[2] 任继鹏[1] 相秀娟[1] 何骞[1] 郭景恒[1] 

机构地区：[1]中国农业大学资源与环境学院,北京100193 [2]中国科学院生态环境研究中心,北京100085

出　　处：《环境化学》2011年第6期1136-1139,共4页Environmental Chemistry

基　　金：国家重点基础研究计划(973)项目(2005CB422206);国家自然科学基金项目(40773049)资助

摘　　要：基于模拟实验和原位观测,建立了适合我国南方酸性土壤的铝活化参数化模型.模拟实验发现,尽管Al3+的活度随着浸提液pH值(pHw)的下降而显著增加(pAl=1.20pHw-0.30),但同时受到土壤pH值(pHs)的显著影响(p<0.01).为反映土壤酸化程度(pHs)对铝活化过程的影响,假设三水铝石的pKsp随土壤pH值的降低而升高,并在此基础上将土壤pH值(pHs)引入传统三水铝石溶解模型(pAl=3pHw+pKsp),建立土壤铝活化过程的参数化模型.模拟实验中三水铝石pKsp偏离无定型三水铝石pKsp(=-10.80)的程度(即pKsp偏离度Y)与土壤pH值的关系为:Y=-1.92pHs+10.80.由此推导出铝活化参数化模型为:pAl=3pHw-1.92pHs.利用原位观测结果验证后发现,参数化模型计算结果与原位观测结果吻合良好,说明该模型可以在南方其它酸性土壤中应用.A parameterized model was developed to interpret soil aluminium mobilization in acidic forest soils,using laboratory experiment and field monitoring data.Experiment data showed that empirical fit between pAl and pHw in soil extracts was pAl=1.20pHw-0.30,and Al3＋activities were significantly influenced by soil pH（pHs）.To consider the influence of soil acidity on aluminum mobilization,pHs was incorporated into the commonly used gibbsite model based on the assumption that solubility product constant（pKsp） of gibbsite minerals decreased with soil pHs.In experimental extracts,pKsp deviation（Y） decreased with pHs following the equation of Y=-1.92pHs＋10.80.From such relationship,we deduced the parameterized aluminum mobilization model as pAl=3pHw-1.92pHs.To evaluate its regional applicability,the parameterized model was used for 6 forest catchments where long term field monitoring was conducted.Satisfactory agreement between modeled and monitored Al was found,which indicated the regional applicability of the parameterized model.

关 键 词：参数化模型 土壤铝活化 土壤酸化 酸沉降 

分 类 号：X131.3[环境科学与工程—环境科学]