西辽河不同粒级沉积物对磷的吸附特征

采用平衡吸附法研究了西辽河不同粒级沉积物对磷的吸附特征.结果表明,不同粒级沉积物对磷的吸附特征圴符合Langmuir吸附等温式和Freundlich吸附等温式;黏粒级和粉粒级的磷饱和吸附量较大,分别为3791.12,2323.33mg/kg,分别相当于粗砂的6.68和4.09倍;黏粒级和粉粒级沉积物吸附的磷是磷素循环的重要组成部分,西辽河冲泻质泥沙黏粒和粉粒所携载的吸附态磷的理论入海通量分别为3791.12,2323.33mg/kg冲泻质泥沙.占沉积物磷吸附总量的28.30%.沉积物对磷的比表面积标化吸附分配系数与松结态腐殖质相关性最大,比表面积标化饱和吸附量与稳结态腐殖质相关性最大,在稳结态和紧结态腐殖质所形成的团聚体结构沉积物中存在孔隙填充方式的磷吸附.

Adorption characteristics of phosphorus from different grain sizes sediment in western liao river

Batch experiments of equilibrium adsorption were carried out to investigate the characteristics of phosphorus from different grain sizes sediment in Western Liao River.The results indicated that phosphorus sorption characteristics of different grain size sediment conformed with the Freundlich and Langmuir isotherm.Clay and silt adorption capacity had greater numbers relatively,and values were 3791.12mg/kg and 2323.33mg/kg respectively,which were equivalent to 6.68 and 4.09 times of coarse sand.Besides,phosphorus from clay and silt adsorption was an important part of the sediment phosphorus cycling,entrance flux were 3791.12mg/kg and 2323.33mg/kg adsorbed phosphorus per kilogram suspend silt respectively,which carried by wash load from Western Liao River to the sea.Furthermore,the proportion of wash load sediment in total phosphorus adsorption was 28.30%.In addition,the study results indicated there was a high correlation between normalized partition coefficient and loosely combined humus.Otherwise,phosphorus sorption capacity had a high correlation with stably combined humus.There might be micro-hole filling sorption mechanism on aggregate structure formed by stably and tightly combined humus.