典型矿区河岸生态区重金属在“水—底质—植物”系统中的迁移富集效应  

Migration and enrichment of heavy metals in the “water-sediment-plant” system from typical riparian ecotope of mining area

作　　者：俞佳 黄颖 刘云根[1,2] 王妍 杨思林[1,2] 张慧娟 YU Jia;HUANG Ying;LIU Yungen;WANG Yan;YANG Silin;ZHANG Huijuan(College of Ecology and Environment,Southwest Forestry University,Kunming,Yunnan 650224,China;Key Laboratory of Ecological Environment Evolution and Pollution Control in Mountainous and Rural Areas of Yunnan Province,Kunming,Yunnan 650224,China)

机构地区：[1]西南林业大学生态与环境学院,云南昆明650224 [2]云南省山地农村生态环境演变与污染治理重点实验室,云南昆明650224

出　　处：《福建农林大学学报（自然科学版）》2021年第6期850-857,共8页Journal of Fujian Agriculture and Forestry University:Natural Science Edition

基　　金：国家自然科学基金项目(41761098、21767027);云南省科技计划项目(2019FB070)。

摘　　要：以云南省文山州内跨境河流小白河生态区为研究对象,研究矿区河岸生态区重金属在"水—底质—植物"中的迁移转化规律以及综合评估生态恢复的效果.分别于冬、夏两季进行野外采样,对水体、底质、植物中的重金属砷(As)、镉(Cd)、铬(Cr)和锌(Zn)的含量、形态及其转运富集特性进行测定和分析.结果表明:(1)生态区底质中As、Cd、Cr和Zn污染程度较严重,平均含量分别是云南省土壤背景值的150.17、52.21、1.33和9.11倍;水体环境中的重金属污染程度相对较低,As、Cr、Zn含量分别为0.03~0.18、0.05~0.06、0.01~0.16 mg·L^(-1),Cd含量低于检出限;香蒲中的Cd和Zn含量富集最多,芦苇和香蒲中As、Cd和Zn含量均表现为夏季高于冬季.(2)As、Cr和Zn在底质中的赋存形态以残渣态为主,约占所有形态的75%~95%,且残渣态含量在冬、夏季波动较大,河流水位和植物类型是影响底质中重金属形态变化的重要因素.(3)生态区不同植物对于重金属的富集和吸收主要与底质中重金属不同形态的含量占比以及季节变化有关.因此,应综合考虑污染区域的重金属种类和水位变化情况,选择适合的植物种类和栽种方式进行污染区域的治理和修复.To evaluate the outcome of ecological restoration in mining-contaminated area, the migration and transformation of heavy metals in "water-sediment-plant" system were investigated along the mining area of Xiaobaihe River, a cross-border river in Wenshan Prefecture of Yunnan Province. The contents, fractions and distributions of heavy metals, including arsenic(As), cadmium(Cd), chromium(Cr), and zinc(Zn), in water, sediments and plants were assessed in summer and winter, based on which the transport and enrichment characteristics were summarized. The results showed that:(1) the sediments of the ecological zone were relatively polluted by As, Cd, Cr, and Zn, which were150.17, 52.21, 1.33, and 9.11 times of the soil background values in Yunnan Province, respectively. However, the water body was less polluted, with As, Cr and Zn ranging between 0.03-0.18, 0.05-0.06 and 0.01-0.16 mg·L^(-1), respectively, and Cd being undetectable. Typha orientalis had the highest levels of Cd and Zn, and the accumulations of As, Cd and Zn in T.orientalis and Phragmites communis in summer exceeded those in winter.(2) Residual form was the dominant form of As, Cr and Zn in the sediments, accounting for approximately 75%-95% of all the metal fractions studied. The residual form content fluctuated greatly in winter and summer. Water level and plant type were the main influencing factors of metal faction in sediment.(3) The enrichment and absorption of heavy metals in plants were closely related to mass distribution ratios of different forms of heavy metals in the sediment and season. Therefore, comprehensive considerations should be made on the type of heavy metal targeted and water level as well as right plant species and cultivation mode during in the ecological restoration of heavy metal contaminated areas.

关 键 词：河岸生态区 重金属污染 富集效应 迁移转化 

分 类 号：X171[环境科学与工程—环境科学]