中文摘要：

以北京大兴南海子湖表层沉积物为研究对象,测试分析了粒径φ〈0.246mm、泥沙在含沙质量浓度为5、10、30、50g·L-1对磷的吸附过程,以及细砂（〉0.147～0.246 mm）、极细砂（〉0.074～0.147 mm）、粉粒（〉0.038 5～0.074 0mm）和粉粒粘粒混合物（≤0.038 5mm）4种粒径泥沙在不同pH值条件下对磷的吸附行为.研究结果表明：二级动力学方程能够比较理想地反映南海子泥沙对磷的吸附动力学过程（R2〉0.98）,吸附平衡时单位质量泥沙饱和吸附量由大到小排序为：粉粒黏粒混合物（0.107mg·g-1）、粉粒（0.096mg·g-1）、细砂（0.095mg·g-1）、极细砂（0.051mg·g-1）·pH值对极细砂、粉粒、粉粒黏粒混合物影响相似,pH值为4～10之间,吸附量变化不大,在pH〉10时,吸附量降低,pH〈4时,吸附量升高.在磷初始质量浓度ρ0〉1.2mg·L-1时,随着泥沙质量浓度增大水溶液中磷吸附的绝对量升高,从最大吸附容量（Xm）来看,单位质量泥沙吸附磷量降低,泥沙之间对磷的吸附存在竞争且与磷初始质量浓度有关.

英文摘要：

Surface sediments was collected from Nanhaizi Lake,Beijing.Phosphorus adsorption by sediments 0.246 mm showed that sediment mass concentration was 5、10、30 and 50 g·L-1.Effect of pH on phosphorus adsorption for four particle size sediments included fine sand（0.147-0.246 mm）,very fine sand（0.074-0.147 mm）,silt（0.0385-0.0740 mm）,mixture of silt and clay（≤0.0385 mm）.Data showed that the second order kinetics model could well describe the behaviors of phosphorus sorption with determination coefficients of R2（0.98）.The saturation adsorption capacity（Cse） of different size particles was in the following order： silt and clay（0.107 mg·g-1）,silt（0.096 mg·g-1）,fine sand（0.095 mg·g-1） and very fine sand（0.051 mg·g-1）.The impact of pH on the very fine sand,silt,silt and clay mixture was similar.When pH was between 4 and 10,the adsorption capacity remained unchanged.The adsorption decreased with pH10,and the adsorption capacity increased at pH4 for phosphorus initial mass concentrations 1.2 mg·L-1.With the increase of sediment mass concentration,the absolute phosphorus adsorption amount increased.However,the unit mass sorption decreased,and there was a competitive adsorption among sediments and related phosphorus initial mass concentrations.