博斯腾湖表层沉积物元素地球化学特征及重金属污染评价  

Geochemical characteristics of major and trace elements and heavy metal pollution status in surface sediment of Bosten Lake

作　　者：刘文[1,2] 吉力力.阿不都外力[1,2] 马龙 LIU Wen;Jilili·Abuduwaili;MA Long(State Key Laboratory of Desert and Oasis Ecology,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China;CAS Research Center for Ecology and Environment of Central Asia,Urumqi 830011,China)

机构地区：[1]中国科学院新疆生态与地理研究所荒漠与绿洲生态国家重点实验室,乌鲁木齐830011 [2]中国科学院中亚生态与环境研究中心,乌鲁木齐830011

出　　处：《地球环境学报》2019年第2期128-140,共13页Journal of Earth Environment

基　　金：中国科学院西部之光(2015-XBQN-B-18);国家自然科学基金项目(41501221);新疆维吾尔自治区2015年高层次人才引进项目~~

摘　　要：重金属是沉积物中一类非常典型的污染物,开展湖泊沉积物元素地球化学的研究具有重要的现实意义。本文对新疆博斯腾湖表层沉积物(0—5 cm)中24种元素含量、粒度、有机碳含量(TOC)等进行了系统分析。受干旱区强蒸发作用的影响,博斯腾湖沉积物Ca、Sr、Mg含量高于新疆土壤元素背景值,Al、Fe、Mn及重金属元素等低于新疆土壤元素背景值。Al、K、Fe及重金属等元素主要受陆源细颗粒物质影响(<4μm、4—16μm),Ba、Na受粗颗粒含量(>63μm)影响,Ca、Sr、Mo、TOC主要来源于湖泊内生作用,与16—63μm颗粒组分相关。Q型聚类将采样点分为3个区域,第Ⅰ区为包括河口区、湖心区及东部湖区的大部分湖区,第Ⅱ区为湖区西侧黄水沟区,第Ⅲ区为湖区东南角。在空间上,重金属元素与细颗粒组分分布基本一致,而第Ⅱ区部分地区沉积物重金属已受到流域农田排水的影响。总体来说博斯腾湖沉积物重金属元素基本不构成污染。本研究可为湖泊沉积物元素地球化学研究提供参考,对博斯腾湖流域环境管理与规划也有重要价值。Background, aim, and scope Heavy metals are a serious type of contaminant in lake sediments due to their toxicity, durability, non-degradability and bioaccumulation. Therefore, the study about geochemical characteristics, source analysis and pollution status of heavy metals in lake sediments are of great practical significance. Materials and methods Bosten Lake is the biggest freshwater lake in arid region of northwest China. In June 2016, 22 surface sediment samples (0 - 5 cm) were collected in the major district of the lake, and a sediment core with 41 cm-in-length was drilled near the entrance of Kaidu River. Surface sediment samples from Bosten Lake were analyzed for the 24 elements’ concentration, grain size distribution and organic matter content (TOC). Samples of the sediment core were analyzed for 210Pb chronology and geochemical elements. The PIRLA method was used to the elements’ contents before 1950s for obtaining the background values of geochemical elements. R-cluster analysis combined with Pearson correlation analysis were used to acquire the influencing factors of geochemical elements. Q-cluster analysis was used to partition the samples, and the results was tested by one-way analysis of variance. At last, by the use of the background values of geochemical elements, enrichment factors and geoaccumulation index were calculated to evaluate the pollution degree of heavy metals. Results The concentrations of Ca, Sr, Mg were obviously higher and the concentrations of Al, Fe, Mn, Ti, V and heavy metals were lower than Xinjiang Soil background values. R-cluster analysis indicated that, Al, K, Be, Tl, Pb, Co, Zn, Ni, Fe, Cr, V, Ti, Cd, Sb, As, Mg, Cu, Mn, P, Hg and terrestrial fine particulate matter (<4 μm, 4 - 16 μm) were divided into one group, Ba, Na and coarse grain size content (>63 μm) were divided into the second group, and Ca, Sr, Mo, TOC, medium-sized content (16 - 63 μm) formed the third group. Through Q-cluster analysis, the sampling points can be divided into three regions. RegionⅠwa

关 键 词：博斯腾湖 沉积物 元素 重金属 聚类分析 污染评价 

分 类 号：X142[环境科学与工程—环境科学] X824