长江水下三角洲现代沉积速率厘定的新途径:季节性Bio-Si记录  

A New Method to Evaluating Sedimentary Rate on the Yangtze River Subaqueous Delta:Seasonal Sedimentary Record of Bio-Si

作　　者：范德江[1] 齐红艳[1] 孙晓霞[1] 郭志刚[1,2] 杨作升[1] 

机构地区：[1]中国海洋大学海洋地球科学学院海底科学与探测技术教育部重点实验室,山东青岛266100 [2]复旦大学环境科学和工程学院,上海200433

出　　处：《中国海洋大学学报（自然科学版）》2009年第5期1025-1028,共4页Periodical of Ocean University of China

基　　金：国家基础研究发展计划(2005CB422304);国家自然科学基金项目(40976020)资助

摘　　要：长江水下三角洲沉积层中高分辨生物硅(Bio-Si)曲线具有明显的波动规律,记录了该区硅藻生物量的季节性差异,据此对近14年来的沉积速率进行了估算。在1992～2005年里,该处沉积速率变化于1.2～3.4 cm/a之间,平均沉积速率2.1 cm/a,沉积速率与长江入海沙量具有较好的对应关系。研究结果表明长江水下三角洲Bio-Si沉积记录类似于季节性湖泊中的"年纹",可作为沉积速率估算的新指标。High resolution sedimentary record of biogenic silica on the Yangtze River subaqueous delta fluctuated regularly. The fluctuation reflected seasonal productivity of diatom in that area. Sedimentary rates from 1992 to 2005 were obtained based on the seasonal signal of biogenic silica. They varied from 1.2 to 3.4 cm/a with a mean sedimentary rate at 2.1 cm/a. There was positive correlation between sedimentary rate and sediment discharge from the Yangtze River. The result suggests that biogenic silica signal in the sediment of the Yangtze River subaqueous delta is like the ＇year layer＇ appearing in the seasonal lake, which could be a new indicator to evaluate sedimentary rate.

关 键 词：长江三角洲 沉积速率 季节性 生物硅 

分 类 号：X141[环境科学与工程—环境科学]