Efects of physical and chemical characteristics of surface sediments in the formation of shallow lake algae-induced black bloom  

作　　者：Qiushi Shen Cheng Liu Qilin Zhou Jingge Shang Lei Zhang ChengXin Fan 

机构地区：[1]University of Chinese Academy of Sciences [2]State Key Laboratory of Lake Science and Environment,Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences

出　　处：《Journal of Environmental Sciences》2013年第12期2353-2360,共8页环境科学学报（英文版）

基　　金：supported by the Major National Science and Technology Programs on Water Pollution Control and Treatment(No.2012X0713-005);the Natural Science Foundation of Jiangsu Province(No.BK20118790);the 135 Project of Nanjing Institute of Geography and Lim-nology;Chinese Academy of Sciences(No.Y213518090);the Industry-University-Research Prosepective Joint Research Projects of Jiangsu Province(No.BY2011165)

摘　　要：Surface sediments are closely related to lake black blooms. The dissolved oxygen （DO） distribution and its penetration depth in surface sediments as well as the migration and transformation of redox sensitive elements such as Fe and S at the sediment-water interface are important factors that could influence the formation of the black bloom. In this study, dredged and undredged sediment cores with different surface properties were used to simulate black blooms in the laboratory. The Micro Profiling System was employed to explore features of the DO and ∑H2S distribution at the sediment-water interface. Physical and chemical characteristics in sediments and pore waters were also analyzed. The results showed that sediment dredging effectively suppressed the black blooms. In the undredged treatment, DO penetration depth was only 50 μm. Fe^2＋ concentrations, ∑H2S concentrations, and ∑H2S production rates were remarkably higher in surface sediments and pore waters compared to control and dredged treatments. Furthermore, depletion of DO and accumulation of Fe^2＋ and ∑H2S in surface sediments and pore waters provided favorable redox environments and necessary material sources for the blooms. The study results proved that physical and chemical characteristics in surface sediments are important factors in the formation of the black bloom, and could provide scientific guidance for emergency treatment and long-term pre-control of black blooms.Surface sediments are closely related to lake black blooms. The dissolved oxygen （DO） distribution and its penetration depth in surface sediments as well as the migration and transformation of redox sensitive elements such as Fe and S at the sediment-water interface are important factors that could influence the formation of the black bloom. In this study, dredged and undredged sediment cores with different surface properties were used to simulate black blooms in the laboratory. The Micro Profiling System was employed to explore features of the DO and ∑H2S distribution at the sediment-water interface. Physical and chemical characteristics in sediments and pore waters were also analyzed. The results showed that sediment dredging effectively suppressed the black blooms. In the undredged treatment, DO penetration depth was only 50 μm. Fe^2＋ concentrations, ∑H2S concentrations, and ∑H2S production rates were remarkably higher in surface sediments and pore waters compared to control and dredged treatments. Furthermore, depletion of DO and accumulation of Fe^2＋ and ∑H2S in surface sediments and pore waters provided favorable redox environments and necessary material sources for the blooms. The study results proved that physical and chemical characteristics in surface sediments are important factors in the formation of the black bloom, and could provide scientific guidance for emergency treatment and long-term pre-control of black blooms.

关 键 词：black bloom sediment-water interface DREDGING sediment micro interface lake 

分 类 号：X13[环境科学与工程—环境科学]