疏浚对大连湾生物可利用磷的水体浓度和沉积物-水界面交换通量的影响  

Effects of Dredging Activities on Concentration of Bio-available Phosphorus and Its Exchange Between Sediment and Seawater in Dalian Bay, China

作　　者：张志锋[1] 宗虎民[1] 王燕[1] 

机构地区：[1]国家海洋环境监测中心,大连116023

出　　处：《应用与环境生物学报》2012年第3期426-431,共6页Chinese Journal of Applied and Environmental Biology

基　　金：国家自然科学基金项目(No.40806046)资助~~

摘　　要：利用FeO/CAM复合膜对大连湾已疏浚区与疏浚影响区海水水体中生物可利用磷(Bio-available phosphorus,BAP)浓度和水质指标进行调查,并通过实验室培养法、间隙水浓度梯度估算法和薄膜扩散梯度技术(Diffusivegradients in thin films technique,DGT)法分别测定沉积物-水界面间BAP交换通量.结果表明,由于受到调查海区附近正在进行的疏浚工程的影响,疏浚影响区水体中浊度和悬浮物含量平均值高于已疏浚区,且疏浚影响区水体中BAP的平均浓度(22.2μg L-1)高于已疏浚水体(19.5μg L-1);而疏浚影响区叶绿素a和溶解氧的浓度明显低于已疏浚区.沉积物-水界面间BAP交换通量研究结果显示,BAP主要由沉积物向上覆水中扩散,沉积物是BAP交换的源;间隙水浓度梯度估算法和DGT法测定的BAP交换通量相似,但远低于实验室培养法测定值;BAP在已疏浚区沉积物-水界面间的交换通量小于疏浚影响区,说明在一定时间内疏浚可以减弱沉积物内源磷的释放.The concentrations of bio-available phosphorus（BAP） in the seawater of dredged and dredging affected areas in the Dalian Bay,China were investigated by using a homemade FeO/CAM membrane,and the water quality indexes were also studied.Furthermore,the exchange fluxes of BAP between sediment and seawater in the Dalian Bay were studied by the methods of laboratory incubation experiment,estimate for nutrient concentration gradient in the pore water and DGT.The results showed the concentrations of BAP,suspended substance and turbidity in the seawater of dredging affected areas（22.2 μg L-1） were higher than those in the dredged areas（19.5 μg L-1）,respectively,influenced by the dredging activities near the sampling station,but the concentrations of chlorophyll a and DO in the seawater of dredging affected areas were lower than those in the dredged areas,respectively.The results of the studies on the exchange fluxes of BAP between sediment and seawater showed that the BAP was released from sediment to seawater,and sediment was the source of BAP transfer.The exchange fluxes of laboratory incubation experiment were much higher than those of the other two methods,respectively.The exchange fluxes in the dredged areas were lower than those in the dredging affected areas,which demonstrated that the internal release of phosphate could be reduced by the dredging activities in a certain time.

关 键 词：疏浚 FeO/CAM膜 生物可利用磷 交换通量 大连湾 

分 类 号：X55[环境科学与工程—环境工程]