基于粒度的土壤团聚体中砷的形态分布特征  

Distribution Characteristics of Arsenic Fractions in Soil Aggregates Based on Particle Size

作　　者：赵然然[1,2] 张志国[1] 李晓军[2] 仝冬丽 李娜[2,3] 侯梅芳[1] 

机构地区：[1]上海应用技术学院生态技术与工程学院,上海201418 [2]中国科学院沈阳应用生态研究所,中国科学院污染生态与环境工程重点实验室,辽宁沈阳110016 [3]中国科学院研究生院,北京100049

出　　处：《生态环境学报》2016年第2期327-332,共6页Ecology and Environmental Sciences

基　　金：国家自然科学基金项目(41101295;41271336;41201310)

摘　　要：为明确土壤团聚体对砷分布和形态的影响,探讨污染农田中砷的可移动性及其环境风险,采集辽宁省某冶炼厂周边污染与非污染(对照)农田表土,采用湿筛法获得>2 mm、2~0.25 mm、0.25~0.053 mm和<0.053 mm 4个粒级的团聚体,分析明确了污染与对照土壤团聚体中全砷及污染土壤团聚体中各提取态砷的分布特征。结果表明,污染土壤<0.25 mm粒级团聚体含量(78.49%)以及其中砷的分配量(80.83%)均显著高于对照土壤(64.33%、67.8%),其中0.25~0.053 mm粒级团聚体中砷的分配量最高(43.13%)。>2 mm、0.25~0.053 mm以及<0.053 mm粒级团聚体中各形态砷分布规律一致:残渣态(20.21~99.10 mg·kg^(-1))>铁锰氧化物结合态(13.38~26.39 mg·kg^(-1))>专性吸附态(5.19~8.86 mg·kg^(-1))>非专性吸附态(1.13~2.94mg·kg^(-1))。而2~0.25 mm粒级团聚体中各形态砷为:残渣态(85.91 mg·kg^(-1))>专性吸附态(28.48 mg·kg^(-1))>铁锰氧化物结合态(25.63 mg·kg^(-1))>非专性吸附态(6.00 mg·kg^(-1))。非专性吸附态和专性吸附态砷在>0.25 mm粒级团聚体中的含量显著高于<0.25 mm粒级团聚体。Allocation and forms of arsenic in different soil aggregates were tested to better understand the mobility andenvironmental risk of arsenic. Water stable aggregates （〉2 mm, 2~0.25 mm, 0.25~0.053 mm, and 〈 0.053 mm） were separated fromthe polluted and non-polluted （as the control） brown soils collected from the farmlands around a smelter in Liaoning Province. Theresult indicated that, the 0.25~0.053 mm aggregates in the polluted soil contributed most to the total As content （43.13%）; both thecontent （78.49%） of aggregates and the allocation （80.83%） of arsenic in the 〈 0.25 mm aggregates from the polluted soil wassignificantly higher than that from the non-polluted soil （64.33% and 67.8%） （P〈0.05）. The distribution pattern of arsenic fractions inin 〉2 mm, 0.25~0.053 mm and 〈 0.053 mm aggregates was consistent and was with an order of residual arsenic （20.21~99.10mg·kg-1） 〉 Fe/Mn oxides co-precipitated arsenic （13.38~26.39 mg·kg-1） 〉 specially adsorbed arsenic （5.19~8.86 mg·kg-1） 〉non-specially adsorbed arsenic （1.13~2.95 mg·kg-1）. While the contents of arsenic fractions in 2~0.25 mm aggregates was in theorder： residual arsenic （85.91 mg·kg-1） 〉 specially adsorbed arsenic （28.48 mg·kg-1） 〉 Fe/Mn oxides co-precipitated arsenic （25.63mg·kg-1） 〉 non-specially adsorbed arsenic （6.00 mg·kg-1）. The contents of non-specially and specially adsorbed arsenic in the 〉 0.25mm were higher than that in the 〈 0.25 mm.

关 键 词：污染土壤 团聚体 砷 形态 

分 类 号：X131.3[环境科学与工程—环境科学]