摘要
对铁岭地区农田土壤重金属Cd、Pb全量和DTPA可提取态量及其相应的玉米、水稻、蔬菜农作物中的重金属含量进行了分析。结果表明,铁岭地区蔬菜土受Cd污染最严重,超标率为40%,水稻土中Cd的超标率为6.67%,玉米土中Cd未有超标;该区3种作物农田土壤未受到环境Pb的影响,农田土壤Pb含量均低于自然背景值35 mg kg-1。该区农田土壤Cd的有效性强于Pb,表现为3种作物农田土壤重金属Cd的DTPA可提取态系数显著(P<0.05)高于Pb。Cd在该地区蔬菜中的污染较为严重,超标率为20%,玉米和大米中Cd均未有超标;Pb在玉米和大米粮食作物中的污染较为严重,超标率分别为26.7%和13.3%,蔬菜中Pb未有超标。玉米、大米、蔬菜对土壤有效态Pb的富集系数大多低于0.2,对土壤有效态Cd的富集系数高于0.2的样本分别占各样本总数的26%、46%6、0%,3类作物对Cd的富集能力要强于Pb,而蔬菜对Cd的富集能力要强于大米和玉米。
Ninety soil samples and corresponding maize,rice and vegetable samples were collected from Tieling Area of Liaoning Province,and total and DTPA-extractable concentrations of heavy metal Cd and Pb for the samples were measured.The results showed that vegetable-farming soils affected by Cd pollution were more serious than rice-farming soils.The Cd concentrations in 40% of vegetable-farming soils and 6.67% of rice-farming soils were higher than standard,respectively.While the Cd concentrations in maize-farming soils were lower than ＂Environmental quality standard for soils＂（GB15618-1995）.Farming soils were not affected by heavy metal Pb in the environment.The Pb concentrations in three type farming soils were lower than 35 mg kg-1.DTPA-extractable factors of heavy metal Cd in farming soils were significant（P 0.05）higher than heavy metal Pb.The Cd concentrations in 20% of vegetable samples were higher than ＂Pollution-Free vegetables standard＂（GB18406.1-2001）,the Pb concentrations of all vegetable samples were lower than the standard.However,the Cd concentrations in maize and rice samples did not exceed ＂Maximum levels of contaminants in foods＂（GB2762-2005）,the Pb concentrations in 26.7% of maize samples and 13.3% of rice samples were higher than levels.In studied area,the vegetables affected by Cd pollution were more serious than maize and rice,but the latter affected by Pb pollution were more serious than the former.Bioconcentration factors of available Pb in soils by maize,rice and vegetable were almost lower than 0.2,but the samples that bioconcentration factors of available Cd were higher than 0.2 accounted for 26%、46%、60% of each thirty samples.Accumulation of available Cd in soils by maize,rice and vegetable were stronger than Pb,accumulation of available Cd in soil by vegetables were stronger than maize and rice.
出处
《土壤通报》
CAS
CSCD
北大核心
2010年第5期1175-1179,共5页
Chinese Journal of Soil Science
基金
农业部国家公益性行业科研专项计划项目"绿色农业科学研究与示范"(2007-10)资助
关键词
铁岭
CD
PB
全量
DTPA可提取态
富集系数
Tieling
Cd
Pb
total concentrations
DTPA-extractable factors
accumulation
