草业学报2017，Vol.26Issue(10)：237-244,8.DOI:10.11686/cyxb2016499
黔北轻污染耕地12种优势杂草重金属含量及富集特征
Heavy metal absorption and enrichment characteristics of dominant weed species naturally growing on farmland in Northern Guizhou
摘要
Abstract
The aim of this research was to provide reference data for the remediation of sites contaminated by heavy metals in Guizhou Province,a mountain-and-hill area.The heavy metal absorption and enrichment characteristics of 12 dominant weeds naturally growing in farmland in northern Guizhou and their root soils were analyzed.The weeds were sampled from the field,and the soils were analyzed to determine the background concentrations of heavy metals.The quality of the soil environment with reference to heavy metal pollution was judged against the Agricultural Environment Quality Evaluation Standards,and on the basis of the single factor pollution index and the Nemerow pollution index.The bioconcentration factor and transfer factor were calculated to evaluate the enrichment characteristics of the dominant weeds.The soil had single factor pollution indexes for Cu,Zn,Cd,and Pb ranging from 0.30 to 1.71 and a Nemerow comprehensive pollution index of 1.31.Therefore,the soil was judged as lightly polluted,and Cd was the main contributor.The dominant weeds in the study area were Acalypha australis,Solanum nigrum,Artemisia argyi,Lapsana apogonoides,Digitaria sanguinalis,Abelnoschus esculentus,Viola verecunda,Amaranthus spinosus,Gynura crepidioides,Youngia heterophylla,Clinopodium chinensis,and Allium fistulosun.The ranges of heavy metal contents in these weeds were as follows:Cu,42.15-110.27 mg/kg;Zn,35.89-157.87 mg/kg;Cd,0.29-6.08 mg/kg;and Pb,2.99-37.19 mg/kg.These values were within the normal range and were not indicative of hyperaccumulating plants.The bioconcentration factors and transfer factors were greater than 1 in A.australis,A.esculentus,and G.crepidioides for Cu,Zn,and Cd;in L.apogonoides for Cu and Zn,and in V.verecunda,A.spinosus,and Y.heterophylla for Cd.These species showed some characteristics of hyperaccumulation plants.The contents of heavy metals in lightly polluted farmland soil did not significantly affect the heavy metals contents in weeds.The absorption of Ph by the roots of weeds promoted Pb accumulation.In conclusion,the contents of heavy metals in the dominant weeds were in the normal range,but some dominant weeds possessed some important characteristics of hyperaccumulation plants,and have the potential to be hyperaccumulation plants.关键词
黔北耕地/优势杂草/重金属/富集特征Key words
farmland of Northern Guizhou/dominant weed plants/heavy metal/enrichment characteristics引用本文复制引用
严莲英,范成五,赵振宇,刘桂华,胡岗,秦松..黔北轻污染耕地12种优势杂草重金属含量及富集特征[J].草业学报,2017,26(10):237-244,8.基金项目
贵州省农业科学院项目“阿哈水库底泥农业资源化利用研究”(农科院创新专项[2015]01号),贵州省科研机构服务企业行动计划项目“贵州农产品产地重金属检测与控制技术研发平台建设”(黔科合服企[2015]400号)和贵州省科技厅科技计划项目“镉低积作物筛选及土壤镉污染控制技术研究与示范”(黔科合NY[2013]3077号)资助. （农科院创新专项[2015]01号）
