香溪河库湾沉积物及库岸土壤对磷的吸附特征  

Dynamics of Phosphorus Adsorption in the Sediments and Soils in Xiangxi Bay

作　　者：罗玉红[1,2,3] 聂小倩[2,3] 胥焘[2,3] 王林泉[1,2,3] 黄应平[1,2,3] 

机构地区：[1]三峡大学水利与环境学院,湖北宜昌443002 [2]三峡大学三峡地区地质灾害与生态环境湖北省协同创新中心,湖北宜昌443002 [3]三峡大学三峡库区生态环境教育部工程研究中心,湖北宜昌443002

出　　处：《三峡大学学报（自然科学版）》2017年第6期98-103,共6页Journal of China Three Gorges University：Natural Sciences

基　　金：国家水体污染控制与治理科技重大专项(2012ZX07104-003-04);湖北省科技惠民计划项目(S2013GMD100042);湖北省自然科学基金创新群体项目(2015CFA021)

摘　　要：采集香溪河沉积物及库岸土壤,进行磷的吸附动力学实验和等温吸附实验,研究吸附特性.结果表明准二级动力学模型为描述香溪河土壤磷吸附的最优方程(R2:0.997 9~0.999 8);垂直方向上,沉积物对磷的吸附能力较库岸土壤更强;时间上,夏季沉积物对磷的最大吸附量为273.16mg/kg,秋季最大吸附量为415.31mg/kg,夏季沉积物对磷的吸附能力较秋季弱.根据Langmuir模型对等温吸附线性拟合得到的最大吸附量(Q_(max))、平衡吸附系数(KL)和最大缓冲容量(MBC)空间差异较大,Q_(max)所得规律与等温吸附线实际规律一致;Q_(max)、KL和MBC均表现为秋季吸附量大于夏季吸附量.沉积物的本底吸附态磷NAP和沉积物对磷的吸附解吸平衡浓度EPC0高于消落带及上缘土壤,其磷释放风险更大;沉积物EPC0浓度高于上覆水P浓度,香溪河沉积物表现为"源".The adsorption experiment for the sediments and reservoir bank soil in Xiangxi Bay was implemen- ted to explore the adsorption performances by calculating the adsorption parameters. The results indicate that a quasi-second order kinetic model was the most suitable model describing the phosphorus adsorption （R2 .0. 9979~0.9998）. The adsorption capacity of sediment for phosphorus was stronger vertically than that of reser- voir bank soil. The maximum adsorption of phosphorus for sediment was 273.16 and 415.31 mg/kg in the summer and autumn, respectively. The special differences of maximum adsorption capacity （Qmax）, equilibri- um sorption coefficient （KL） and maximum buffer capacity （MBC）, acquired by fitting the Langmuir iso- therm model, were significant. The Q fitted value was in accordance with actual value, and the Q KL, and MBC in autumn were bigger than those in summer. Native adsorbed phosphorus （NAP） and equilibrium phosphate concentration （EPC0） in the sediment in Xiangxi Bay were larger than those in reservoir bank soil, indicating a larger releasing risk of phosphorus. The equilibrium phosphate concentration in the sediment was higher than the phosphorus concentration in the overlying water, manifesting the sediment in Xiangxi Bay as the pollution source.

关 键 词：香溪河 沉积物 库岸土壤 磷 迁移/转化 

分 类 号：X53[环境科学与工程—环境工程]