贵州西部燃煤电厂周边土壤和玉米中砷含量的空间变化特征

摘要

通过对贵州西部某燃煤电厂周边的土壤及玉米植株进行采样调查，分析探讨电厂周边土壤及玉米砷污染的空间变化特征。结果表明，该燃煤电厂周边土壤中砷的含量范围为13．49～33．06 mg/kg，平均值为21．35 mg/kg，土壤砷含量出现一定程度的富集。电厂周边玉米植株根、茎叶、粒中砷的浓度范围分别达1．23～4．04 mg/kg、0．26～1．77 mg/kg和0．03～0．45 mg/kg，平均值分别为2．83 mg/kg、0．81 mg/kg和0．15 mg/kg；玉米粒样品中有22．20％超过《食品中污染物限量》（GB2762-2005）标准规定的砷含量限值0．20 mg/kg。玉米的As含量在距离中心点（电厂烟囱）1．0 km达到最高值。玉米各部分的As含量与土壤的As含量均呈正相关。%Based on the study of soils sampling and corn plants sampling around a coal-fired power plant in Guizhou,spatial variation characteristics of arsenic pollution in those soils and corns around the coal-fired power plant were?analyzed.Results:Arsenic content of soils around the coal-fired power plant were in the range of 13.49 ~ 26.45 mg/kg,with an average of 21.35 mg/kg.It showed that the soil enriched arsenic in a certain degree.Arsenic content of corn plant roots,stems and leaves,niblets around the coal-fired power plant were in the range of 1.23 ~ 4.04 mg/kg,0.26 ~ 1.77 mg/kg,0.03 ~ 0.45 mg/kg respectively,with their average of 2.83 mg/kg,0.81 mg/kg,0.15 mg/kg.Arsenic content of 22.2%corn niblets sampling were more than the limited value 0.2 mg/kg of Contaminants in Food (GB2762-2005)standard.Arsenic content of corn at the 1.0 km distance from the center (power plant chimney)was the largest.Arsenic content of various parts of corn plants were significantly positively related to arsenic content of soils.