广西重金属高背景地区石漠化程度对土壤汞形态及迁移特征影响  

Effects of rocky desertification degree on mercury forms and migration characteristics in soils of high-heavy-metal background area in Guangxi

作　　者：叶丽丽[1] 熊林[1,2] 陈余道[2] 陈永山 宋波[1,2] 蒋金平[1,2] YE Li-li;XIONG Lin;CHEN Yu-dao;CHEN Yong-shan;SONG Bo;JIANG Jin-ping(Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology,Guilin University of Technology,Guilin 541006,China;Guangxi Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Area,Guilin University of Technology,Guilin 541006,China;School of Resources and Environmental Science,Quanzhou Normal University,Quanzhou 362000,China)

机构地区：[1]桂林理工大学广西环境污染控制理论与技术重点实验室,`广西桂林541006 [2]桂林理工大学广西岩溶地区水污染控制与用水安全保障协同创新中心,`广西桂林541006 [3]泉州师范学院资源与环境科学学院,福建泉州362000

出　　处：《桂林理工大学学报》2021年第4期877-883,共7页Journal of Guilin University of Technology

基　　金：国家自然科学基金项目(41661097);广西自然科学基金项目(2020GXNSFAA297124)。

摘　　要：广西石漠化分布较广且已成为严重的生态问题之一,部分石漠化地区的土壤汞(Hg)污染问题比较突出。为了深入了解石漠化程度对重金属汞形态及迁移态影响,采集环江县汞地质背景值较高的不同石漠化程度土壤(潜在石漠化、轻度石漠化、中等石漠化和重度石漠化),并采用美国环保署推荐的三步连续萃取法,对汞的形态(移动态、半移动态和不可移动态)进行了分析,探讨了土壤中不同组分汞含量与土壤性质之间的关系,以及不同石漠化等级土壤汞的移动性和转化规律。结果表明:汞高地质背景石漠化土壤中汞含量在0.3~4.5 mg/kg,平均约3.46 mg/kg;土壤汞形态以半移动态汞为主要形态,约69%~80%,平均为75.3%;土壤pH、阳离子交换量、土壤有机质与可移动态汞呈显著负相关(P<0.01),而土壤总铁、总锰、总铝、游离氧化铁、游离氧化锰与3种形态汞均呈显著正相关(P<0.01);石漠化程度的加剧促进了土壤中总汞浓度提高,也促进了土壤汞形态向可移动态汞转化,增加了土壤汞的移动性。Rocky resertification in Guangxi is widely distributed and becomes one of the serious ecological problems.The Hg pollution in some rocky desertification areas is more prominent.In order to understand the influence of rocky desertification degree on speciation and mobility of heavy metal mercury,different rocky desertification soils(potential rocky desertification,light rocky desertification,medium rocky desertification and severe rocky desertification)with high mercury background value were collected in Huanjiang of Guangxi.The mercury speciation was analyzed by three-step continuous extraction method recommended by Environmental Protection Agency(The mercury was divided into moving dynamic,semi-dynamic and non-moving dynamics).The relationship between mercury content and soil properties of different components in soil,and the mobility and transformation law of mercury in soils of different rocky desertification grades were discussed.The results showed that the content of mercury in high background rocky desertification soil ranged from 0.3 to 4.5 mg/kg,with an average of 3.46 mg/kg.The main form of mercury was half migration,accounting to 69%-80%of the total mercury content,with an average of 75.3%.The pH,cation exchange capacity,organic matter and mobile mercury were negatively correlated,while the total iron,total manganese,total aluminum,free iron oxide and free manganese oxide were positively correlated.The degree of rocky desertification promoted the increase of total mercury concentration,but also promoted the transformation of soil mercury form to mobile mercury,and the mobility of soil mercury.

关 键 词：石漠化 土壤污染 汞 形态分析 迁移特征 

分 类 号：X53[环境科学与工程—环境工程]