天津市典型污灌区冬小麦各生育期的重金属分析  

HEAVY METAL ANALYSIS OF WINTER WHEAT AT EACH STAGE IN TYPICAL SEWAGE IRRIGATED AREA OF TIANJIN

作　　者：马传鑫[1] 汪志荣[1] 高琼[1] 金星龙[1] 何莎[1] 

机构地区：[1]天津理工大学环境科学与安全工程学院,天津300384

出　　处：《环境化学》2010年第1期44-47,共4页Environmental Chemistry

基　　金：天津市教委项目(20060520)资助

摘　　要：通过对天津市冬小麦生长的各个阶段的各个部位及土壤中重金属含量的分析,评价了污灌区农田土壤-植被系统的污染状况,运用转运系数和富集系数表征了重金属元素在作物中迁移和积累的能力.结果表明,冬小麦田土壤质量属2级尚清洁标准,土壤中Cd污染最严重,Hg污染次之.返青期、拔节期、抽穗期和成熟期,同一时期冬小麦不同部位的重金属含量整体呈现自下至上递减的趋势,即根>茎>叶>果实,而同一部位冬小麦的不同时期的重金属含量各有特点.从转运系数和富集系数上看,根富集重金属的能力要大于茎、叶和果实;重金属由土壤向根迁移的过程中,迁移能力顺序为:Pb>Cd>Hg>Cr>As,Pb迁移能力最强.冬小麦果实中As,Cd,Cr,Hg,Pb和Se含量均超过《食品中污染物限量》中规定的限值,说明研究区域目前已经不宜再种植冬小麦.Based on the analysis of heavy metal content of wheat and soil at different period,the contamination extent of soil-plant system is assessed,and transportation factor（TF）and bio-concentration（BCF）are used to describe heavy metal ability of transportation and deposition in winter wheat.From the results,soil quality of winter wheat field in xiqing district,Tianjin,belongs to levels 2,the highest pollutant is Cd,Hg is second.At different stages,including turn green,jointing,heading and ripeness,the content of heavy metals in different parts of winter wheat presents the declining trend from bottom to top,root〉stem〉leaf〉fruit,but in the whole process of growth,the trend of heavy metals in the same parts is different respectively.According to transportation factor（TF）and bio-concentration（BCF）,the ability of roots to absorb heavy metals is stronger than that of stems,leaves and fruits;the ability of heavy metals＇ transportation from soil to root is Pb〉Cd〉Hg〉Cr〉As.As,Cd,Cr,Hg,Pb and Se all exceed the limited values which are enacted by maximum levels of containment in food,so it is clear that planting winter wheat is inappropriate in this area at present.

关 键 词：冬小麦 污灌区 土壤-植物系统 生育期 重金属 

分 类 号：X53[环境科学与工程—环境工程] TP216[自动化与计算机技术—检测技术与自动化装置]