环境微界面对湖泊内源磷释放的影响研究  

The effect of environmental micro-interface on internal phosphorus release of the lake

作　　者：钱宝[1] 刘凌[1] 肖潇[2] 陈立尧[1] 

机构地区：[1]河海大学水文水资源与水利工程科学国家重点实验室,江苏南京210098 [2]南京水利科学研究院,江苏南京210029

出　　处：《水利学报》2013年第3期295-301,共7页Journal of Hydraulic Engineering

基　　金：国家自然科学基金资助项目(51279060);江苏省普通高校研究生科研创新计划(CXZZ11_0436)

摘　　要：为揭示湖泊内源污染物释放的发生机制,从环境微界面角度出发,研究湖泊水-沉积物界面三相结构模式中磷的界面反应过程。利用微电极系统获取微界面溶氧浓度剖面,并结合Profile模型进行分析计算。计算结果表明:该湖湖心区沉积柱含氧层厚度达5mm,而湖口区则不到3mm,湖心区微界面上氧气消耗主要以自由扩散为主,而湖口区受微界面上微生物活动影响较大。同时利用梯度扩散薄膜技术获取了水-沉积物界面上分辨率高达1mm的可溶性活性磷剖面浓度分布,结果表明,在湖口区沉积物表层2cm处有强烈磷释放现象,而在湖心区则未发现,这可能与含氧层厚度有着密切的联系,这一重要现象在常规尺度下可能被掩盖。In order to reveal the mechanism of the environmental micro-interface from the source of pollu tion in lakes , from the point of view of environmental micro-interface in lake , we study the interfacial pro cess of phosphorus in the three-phase structure model of the lake water-sediment interface. The oxygen mi cro-sensor and Diffusive Gradients in Thin-films （ DGT ） were employed to obtain the vertical distribution of the dissolved oxygen and the dissolved reactive phosphorus （ DRP ） in high resolution , respectively. The result combined with Profile model was analyzed and calculated. We find that the aerobic layer thickness of sediment cores in central of Xuan-wu Lake is up to 5mm , and that in the lakeshore is less than 3mm. Oxygen consumption of the micro-interface in the central lake is mainly in the form of diffusion , and in the lakeshore area that affected by the microbial activity in the micro-interface. From the vertical distribu tion in 1mm resolution of DRP in water-sediment interface by DGT device , the results show that at the depth of 2cm in the sediment core from the lakeshore area has a strong releasing phosphorus phenomenon , but that is not found in the central lake , this may be closed linked with the aerobic layer thickness. How ever , this important phenomenon is covered in the conventional scale.

关 键 词：环境微界面 湖泊 微电极 梯度扩散薄膜技术 磷 

分 类 号：X142[环境科学与工程—环境科学]