研究论文
廖敏,黄昌勇,谢正苗.pH对镉在土水系统中的迁移和形态的影响[J].环境科学学报,1999,19(1):81-86
pH对镉在土水系统中的迁移和形态的影响
- Effect of pH on transport and transformation of cadmium in soil water system
- 基金项目：国家自然科学基金
- 作者
- 单位
- 廖敏
- 浙江农业大学环境资源学院土化系,杭州 310029
- 黄昌勇
- 浙江农业大学环境资源学院土化系,杭州 310029
- 谢正苗
- 浙江农业大学环境资源学院土化系,杭州 310029
- 摘要：研究了4种红壤和水体系中pH对镉的迁移影响。结果表明:镉在土水体系中的迁移是一快反应过程,4种土壤对镉的吸附量随土水系统中pH的变化,可分为3个区域,即低吸附量区、中等吸附区,以及强吸附和沉淀区,在中等吸附区镉吸附量与pH呈正相关;pH6以下被吸附的镉中生物有效态镉量随pH的升高而增加,pH6以上被吸附的镉中生物有效态镉量随pH升高而降低。石灰导致镉毒性降低的主要原因是pH>7.5时镉主要以粘土矿物和氧化物结合态及残留态形式存在。
- Abstract：Effects of pH on transport and transformation of cadmium in soil water systems were studied. The results showed that the transport of cadmium in the soil water systems was a fast process.The variation in absorption capacity for cadmium with pH showed three distinct stages,i.e.,low adsorption stage at pH<ZPC,stable adsorption stage at ZPC<pH<6.0 and strong adsorption and precipitation stage at pH>6.0.Adsorption capacity for cadmium was positively correlated with pH at the stable adsorption stage.The bioavailability of adsorbed cadmium increased with pH when pH<6 while decreased with pH when pH>6. At pH value of 7.5,large perceentages of cadmium were bound to clays and oxides,reducing its toxicity.
摘要点击次数： 5295 全文下载次数： 4987
