摘要
为了解三峡工程建成后长江流域颗粒物的风化状况及颗粒态重金属的变化规律和污染程度,于2009年8—10月对长江干流及主要南、北支流悬浮颗粒进行采样调查。本文采用电感耦合等离子体原子发射光谱法(ICP-AES)对颗粒态常量金属(Al、Ca、Fe、K、Na)及重金属(Cr、Zn、Cu、Ni、V)进行测定。利用化学风化指数(CIA)估算长江流域颗粒物的风化程度,结果表明:长江干流的化学风化指数在62~75之间,风化程度下游高于上游,气温、岩石类型及地势是主要的影响因素。长江流域南、北支流颗粒物CIA平均值分别为71和66,主要受岩石类型和南北气候影响,与三峡工程前相比CIA值无明显变化。利用富集因子(EF)估算长江流域颗粒态重金属污染程度,结果表明:总体长江干流及北岸支流污染较轻,仅Cu、Zn处于中等程度富集。南岸支流湘江、螳螂川颗粒态Cu、Zn显著污染,主要受采矿及人为排污的影响。采用因子分析对干流上、下游颗粒态金属的组成进行来源分析,提取了三个因子,结果表明主要受自然来源影响,同时也受到人类活动(大坝拦截、排污)及化学风化影响。
In order to understand the variations of chemical weathering intensities and heavy metal pollutions of the suspended particles in the Yangtze River Drainage Basin after the construction of Three Gorges Dam,suspended particulate samples were collected in the mainstream and the major southern and northern tributaries of Yangtze River in August─October 2009.The concentrations of the major metals(Al,Ca,Fe,K,Na)and the heavy metals(Cr,Zn,Cu,Ni,V)were determined by ICP-AES.Chemical index of alteration(CIA)values are used to assess the weathering intensities of particulate matter in the Yangtze River Drainage Basin.Results show that the CIA values ranges from 62 to 75 in the mainstream of Yangtze River,with strong weathering intensities in the downstream comparing to the upstream.Temperature,rock type and terrain are the main influencing factors on the chemical weathering intensities in the mainstream of the Yangtze River.The average CIA values of the southern and northern tributaries are 71 and 66,respectively,which are mainly influenced by the different rock type and climate.Enrichment factor(EF)is used to assess the degree of heavy metal pollution in the suspended particles.Results show that the heavy metal pollutions in the mainstream of the Yangtze River and the northern tributaries are relatively less important,except for Cu and Zn with middle enrichments.Cu and Zn are heavy polluted in the southern tributaries(e.g.,Xiangjiang and Tanglangchuan)due to the mining and sewage from human activities in the drainage basins.Compared with the dam been construction before,the Three Gorges Project affected the transportation of particulate metals,and there was no significant change in chemical weathering index and historical data.Three factors are extracted to explain the chemical composition of particular matter,which are chemical weathering,natural source and human activity(e.g.,dam construction and sewage).
作者
饶恩铭
任景玲
辛成林
张国玲
RAO En-Ming;REN Jing-Ling;XIN Cheng-Lin;ZHANG Guo-Ling(Key Laboratory of Marine Chemistry Theory and Technology,Ministry of Education,Ocean University of China,Qingdao 266100,China;Laboratory for Marine Ecology and Environmental Science,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266071,China)
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2019年第8期54-65,共12页
Periodical of Ocean University of China
基金
国家重点研究发展计划项目(2016YFA0600902)
国家自然科学基金项目(41676072)资助~~
关键词
颗粒态重金属
颗粒态常量金属
化学风化
分布特征
影响因素
长江流域
particulate heavy metal
particulate major metal
chemical weathering
distribution characteristics
influence factors
Yangtze River drainage basin
