摘要
生态修复是重金属污染河流治理的重要手段之一,以云南省文山州内跨境河流小白河生态修复区为研究对象,探析了不同形态砷在小白河生态修复区沉积物表层(0~10cm)、中层(10~20cm)和底层(20~30cm)的空间分布规律。结果表明:(1)表、中、底层中主要以残余态砷存在;残余态砷随沉积物深度的增加占比逐渐增大。表层中可氧化态砷>弱酸可提取态砷>可还原态砷;中层中可氧化态砷>弱酸可提取态砷>可还原态砷;底层中可氧化态砷>可还原态砷>弱酸可提取态砷。(2)小白河表层沉积物中砷全量总体呈B断面>D断面>C断面。(3)有机质与可还原态、可氧化态砷的结合趋势较大。(4)随着采样深度的增加,可提取态砷明显减少。故在利用该生态修复区进行环境治理时,应该重点针对表层沉积物进行定期清淤,减少该层沉积物的环境风险。
Ecological restoration is one of the most important methods for treating the heavy metal pollution in river. The ecological restoration area of Xiaobaihe, which was across the border between China and Vietnam and main- ly located in Wenshan autonomous prefecture of Yunnan province,was selected as the research object. The sediments in the research area were divided into 3 layers as follows：0-10 cm as the surface layer,10-20 cm as the middle layer and 20-30 cm as the bottom layer. Spatial distribution of different species arsenic from sediments of each layer in Xi- aobaihe ecological restoration area was explored and analyzed. The results showed that：（1） the speciation of arsenic in the surface,middle and bottom layer was mainly the residual state,and the proportion of residual state was gradually increasing with the increase of soil depth. The order of the contents of extractable arsenic in the surface layer follows： oxidation state.weak acid extractable state.reduction state;in the middle layer was：the oxidation state.weak acid extractable state.reduction state; and in the bottom layer was：oxidation state.the reduction state.weak acid ex- tractable state. （2） The total arsenic content in the surface sediments of the Xiaobaihe was section B^sectiona D~ section C. （3） In the ecological restoration area, the organic matter combination with the reduction state and the oxidation state of the trend was relatively large,and there was a extremely significant correlation. （4） With the increase of sampling depth, the spatial distribution characteristics of extractable arsenic was obviously decreasing. Therefore, in the use of the ecological restoration area for environmental management, it should focused on the regular dredging of surface sediments to reduce the environmental risks of the sediments.
作者
张慧娟
刘云根
王妍
侯磊
詹乃才
王书锦
ZHANG Hul- juan LIU Yungen WANG Yan HOU Lei ZHAN Naicai WANG Shujin(College of Environmental Science and Engineering, Southwest Forestry University, Kunming Yunnan 650224 Research Institute of Rural Sewage Treatment ,Southwest Forestry University ,Kunming Yunnan 650224)
出处
《环境污染与防治》
CAS
CSCD
北大核心
2017年第4期392-397,412,共7页
Environmental Pollution & Control
基金
国家自然科学基金资助项目(No.51469030)
云南省应用基础面上项目(No.2009ZC083M)
云南省高校优势特色重点学科(生态学)建设项目
关键词
生态修复区
沉积物
砷
形态
时空分布
ecological restoration area
sediment
arsenic
forms
time and space distribution
