广西阳朔铅锌矿周边土壤和白菜汞含量及污染评价  

Mercury Content and Pollution Assessment of Soil and Cabbage Surrounding Yangshuo Pb-Zn Mining District in Guangxi

作　　者：莫福金 钱建平[1,2] 王远炜 张藜[1,2] 

机构地区：[1]桂林理工大学广西冶金与环境实验中心,广西桂林541004 [2]桂林理工大学地球科学学院,广西桂林541004

出　　处：《生态环境学报》2016年第1期156-161,共6页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(45063001;41073089);中国科学院地球化学研究所环境地球化学国家重点实验室项目(SKLEG8009)

摘　　要：阳朔铅锌矿是广西境内一个较大型的铅锌老矿山。对阳朔铅锌周边耕作区、居民区土壤和白菜(Brassica rapa L.Chinensis Group)汞含量分布及污染进行调查和研究,可以为汞污染防治与修复提供科学依据。在铅锌矿下游耕作区、对照耕作区分别采集土壤样各66、38个,白菜样各35、20个;居民区采集土壤样17个。全部土壤和白菜样品采用MDS-2003F型压力自控密闭微波溶样系统进行消解,并用原子荧光测汞仪进行分析测定。结果表明,阳朔铅锌矿下游耕作区土壤汞质量分数为(0.567 4±0.268 3)mg·kg-1,对照耕作区土壤汞质量分数为(0.147 1±0.039 5)mg·kg-1,居民区土壤汞质量分数为(0.188 0±0.097 2)mg·kg-1,分别为中国一些地区土壤汞的自然含量(0.071 mg·kg-1)的7.99、2.07、2.65倍。在铅锌矿下游耕作区土壤汞含量随着远离矿区方向依次降低。阳朔铅锌矿下游耕作区白菜根汞平均质量分数为27 600 ng·kg-1,茎汞平均质量分数为7 100 ng·kg-1,叶汞平均质量分数为19 300 ng·kg-1;对照耕作区白菜根汞平均质量分数为12 500 ng·kg-1,茎汞平均质量分数为4 800 ng·kg-1,叶汞平均质量分数为10 000 ng·kg-1,白菜汞含量分布特征与土壤汞含量分布相似。白菜植株各部位汞含量与土壤有效态(水溶态、交换态)汞含量显著相关,且根汞与之相关性最为显著,白菜植株不同部位汞含量表现为:根>叶>茎,上述特点表明土壤汞是白菜汞的主要来源。所采土样中有61.2%的土壤样汞含量超过了中国《土壤环境质量标准(GB 15618─2008)》二级标准的最低限值(0.2 mg·kg-1)。铅锌矿下游耕作区土壤汞污染最为严重,中等-严重污染以上占53.0%,中等污染占36.4%;居民区次之,中等污染占35.3%;对照耕作区污染最轻,均在中等污染以下。阳朔铅锌矿耕作区白菜植株各部位汞平均含量均未超过国家相关标准,这表明尽管耕作区土壤总汞严重超标,但由于土壤�Yangshuo Pb-Zn mine is a relatively large mine in Guangxi. The article tries to understand the mercury pollution in soil and cabbage, as well as the transition and transform rule of mercury in soil-vegetables system. Investigation and research about the mercury content distribution and mercury pollution of soil and cabbage in the sourrouding farming area and residential area of Yangshuo Pb-Zn mine was done, in order to provide a scientific basis for mercury pollution prevention and remediation. In the research, 66 soil samples and 35 cabbage samples were collected in farming area of the downstream of Pb-Zn mine, 38 soil samples and 20 cabbage samples were collected in control farming area; 17 soil samples were collected in residential area. All soil and plant samples were digested by MDS-2003F-type pressure-controlled microwave digestion system and were analyzed with atomic fluorescence mercury analyzer. The result showed that the mercury concentration in the downstream arming area of Pb-Zn mine was (0.5674±0.2683) mg·kg-1, the mercury concentration in control farming area was (0.1471±0.0395) mg·kg-1, the mercury concentration in residential area was (0.1880±0.0972) mg·kg-1, which is 7.99, 2.07, 2.65 times higher compared with the natural content (0.071 mg·kg-1) of soil Mercury in some areas. In the downstream farming area of Pb-Zn mine, the soil mercury levels is decreasing when the distance from the mine is increasing. In the downstream farming area of Pb-Zn mine, the average mercury concentration at cabbage root was 27600 ng·kg-1, the average mercury concentration at Cabbage stem was 7100 ng·kg-1, the average mercury concentration at Cabbage leaf was 19300 ng·kg-1; in the control farming area, the average mercury concentration at cabbage root was 12500 ng·kg-1, the average mercury concentration at Cabbage stem was 4800 ng·kg-1, the average mercury concentration at Cabbage leaf was 10000 ng·kg-1. Cabbage mercury distribution characteristics is similar to soil mercury content distribution. The mercu

关 键 词：阳朔铅锌矿 土壤 白菜 汞含量 污染评价 

分 类 号：X53[环境科学与工程—环境工程]