通过三峡水库香溪河库湾的3个采样点沉积物中磷的自然吸附实验和不同粒径下沉积物的胁迫吸附试验,研究了沉积物对磷的吸附特征。结果表明:上覆水中的磷浓度与沉积物中的总磷含量有很好的相关性,沉积物中的总磷含量对上覆水的水质有很大的影响;三点的临界平衡浓度为C1:0.188mg/L,C2:0.147mg/L,C3:0.188mg/L;各点增加的量即饱和吸附量不同(△Q1:268.16mg/kg,△Q2:57.96mg/kg,△Q3:267.27mg/kg),恰恰与三点的临界平衡浓度之间的关系一致;粒径对沉积物对磷的吸附量影响程度与沉积物理化参数也存在很大的关系;三个样点的吸附量,分别接近于1.5mg/g,0.8mg/g及1.4mg/g。结果还表明:最大吸附量大的地方,饱和吸附量不一定就大,二者之间不存在必然的关系;香溪河沉积物中的磷在现有条件下表现为“源”,不排除外在条件改变时转化为“汇”。如果最大吸附容量、饱和吸附容量及平衡浓度能够很好的与数学相结合,可为当地的环保部门管理香溪附近工厂提供科学依据。
Natural adsorption of phosphorus and the phosphorus force adsorption of different grain size on three samples of sediments taken form Xiangxi river Bay Three Gorges Reservoir were determined in laboratory. The results indicated that the total phosphorus (TP) concentration of overlying water was significantly correlated to the TP concentration of sediment, the TP concen- tration of sediment influenced the water quality of the overlying water greatly. The critical equilibrium concentration of three samples were C 1:0.188 mg/L, C2:0.147 nag/L and C3:0.188 mg,/L, respectively. And the saturated adsorption capacities were △Q1 : 268.16mg/kg, △Q2 : 57.96mg/kg, △Q3 : 267.27mg/kg; the two items were consistent. The influence of grain size on phosphorus adsorption was significantly related to the physico-chemical properties of sediment. The adsorption capacities of three unfiltered samples were 1.5mg/g,0.8mg/g and 1.4mg/g respectively. The result also indicated that the saturated adsorption capacities didn't change according to the largest adsorption capacities. The phosphorus in sediment of xiangxi river was a source to overlying water until the environment condition changed. If the saturated adsorption capacities, largest adsorption capacities and critical equilibrium concentration can be correlated mathematically, the Department of the Enviroment will have a scientific basis to administer industries near the Xiangxi River.