【摘要】 采用2. 0 mol/dm³Na₂CO₃溶液5h单点化学提取-硅钼蓝连续分光光度分析法分别测定了大亚湾西部海域13个表层沉积物和1个沉积物岩芯中生物硅的含量.表层沉积物和沉积物岩芯中生物硅含量占比分别为0. 69%～2. 02%和1. 24%～2. 05%,平均值分别为1. 42%和1. 60%.结果证实西大亚湾沉积物中生物硅含量水平与我国南海近岸海域基本一致.在210Pbex测年的基础上,通过分析沉积物岩芯中生物硅、有机物、无机碳等多指标,揭示近百年来大亚湾周边环境变化对海洋环境的影响,证实了上世纪80年代以来西大亚湾周边农业、海水养殖业和工业发展等人类活动加剧了该海域生态环境变化,尤其90年代核电站运行对海洋生态变化造成一定的影响.更多还原

【Abstract】 Thirteen surface sediments and one sediment core were collected from the west Daya Bay( WDB). Biogenic silica( BSi) contents( SiO2%) in the sediments were measured using a single time digestion technique with2. 0 mol/dm3 Na2 CO3 solution and the flow-injection molybdate-blue spectrophotometric method. BSi contents in surface and the core sediments were in the range of 0. 69%-2. 02% and 1. 24%-2. 05%,with mean values of1. 42% and 1. 60%,respectively. As results,BSi contents in the WDB were basically at the similar level as those of other coastal areas of the South China Sea. The profiles of BSi contents,loss on ignition,total organic carbon( TOC) and other factors in the sediment core dated with210 Pbexmethod,were analyzed to reveal the impacts of marine environmental change of the WDB in recent 100 years. The marine environment change in WDB was aggravated due to the aquaculture,agricultural and industrial development and the other human activities since 1980 s,especially the commercial operation of Daya Bay Nuclear Power Plant in 1990 s.更多还原