生态环境学报
生態環境學報
생태배경학보
ECOLOGY AND ENVIRONMENT
2014年
4期
673-678
,共6页
林立金%宁博%廖明安%蓝焕杰%梁欢
林立金%寧博%廖明安%藍煥傑%樑歡
림립금%저박%료명안%람환걸%량환
繁缕(Stellaria media)%镉%积累特性%冬季农田杂草
繁縷(Stellaria media)%鎘%積纍特性%鼕季農田雜草
번루(Stellaria media)%력%적루특성%동계농전잡초
Stellaria media%Cd%characteristics of accumulation%winter farmland weed
为进一步筛选出更多的镉超富集植物作为植物修复的材料，本文以冬季农田杂草作为研究对象，采用土壤种子库-金属筛选法进行筛选，以期从冬季农田杂草中筛选出镉超富集植物，为镉污染农田土壤的冬季植物修复提供材料。通过土壤种子库-金属筛选法初步研究发现，冬季农田杂草繁缕（Stellaria media）地上部分镉含量接近超富集植物的临界值（100 mg·kg-1），但转运系数（TF）小于1，可能是镉富集植物。为此，采用盆栽试验进行了进一步的浓度梯度鉴定。结果表明，随土壤镉含量的增加，繁缕根系生物量、地上部分生物量、主枝长度、根系长度、抗性系数及耐性系数均随土壤镉含量的增加而下降，但繁缕根系及地上部分镉含量呈显著增加的趋势。与对照相比，在土壤镉质量分数为25、50、75、100和125 mg·kg-1时，繁缕总生物量分别下降了17.31%、34.87%、44.79%、52.12%和59.32%，但各个处理均没有表现出明显毒害症状。土壤镉含量为75~125 mg·kg-1时，繁缕地上部分镉含量均大于100 mg·kg-1，最大值为135.79 mg·kg-1，地上部分富集系数（BCF）大于1，但转运系数（TF）小于1。在土壤镉含量为100 mg·kg-1时，繁缕地上部分镉提取量达到最大值，为87.42μg·plant-1。这些结果表明繁缕是一种镉富集植物。虽然繁缕的单株镉提取率较低，但繁缕具有分蘖力强、繁殖力强、生长密度大、耐荫性强等特点，因此适用于冬季农田镉污染的修复。
為進一步篩選齣更多的鎘超富集植物作為植物脩複的材料，本文以鼕季農田雜草作為研究對象，採用土壤種子庫-金屬篩選法進行篩選，以期從鼕季農田雜草中篩選齣鎘超富集植物，為鎘汙染農田土壤的鼕季植物脩複提供材料。通過土壤種子庫-金屬篩選法初步研究髮現，鼕季農田雜草繁縷（Stellaria media）地上部分鎘含量接近超富集植物的臨界值（100 mg·kg-1），但轉運繫數（TF）小于1，可能是鎘富集植物。為此，採用盆栽試驗進行瞭進一步的濃度梯度鑒定。結果錶明，隨土壤鎘含量的增加，繁縷根繫生物量、地上部分生物量、主枝長度、根繫長度、抗性繫數及耐性繫數均隨土壤鎘含量的增加而下降，但繁縷根繫及地上部分鎘含量呈顯著增加的趨勢。與對照相比，在土壤鎘質量分數為25、50、75、100和125 mg·kg-1時，繁縷總生物量分彆下降瞭17.31%、34.87%、44.79%、52.12%和59.32%，但各箇處理均沒有錶現齣明顯毒害癥狀。土壤鎘含量為75~125 mg·kg-1時，繁縷地上部分鎘含量均大于100 mg·kg-1，最大值為135.79 mg·kg-1，地上部分富集繫數（BCF）大于1，但轉運繫數（TF）小于1。在土壤鎘含量為100 mg·kg-1時，繁縷地上部分鎘提取量達到最大值，為87.42μg·plant-1。這些結果錶明繁縷是一種鎘富集植物。雖然繁縷的單株鎘提取率較低，但繁縷具有分蘗力彊、繁殖力彊、生長密度大、耐蔭性彊等特點，因此適用于鼕季農田鎘汙染的脩複。
위진일보사선출경다적력초부집식물작위식물수복적재료，본문이동계농전잡초작위연구대상，채용토양충자고-금속사선법진행사선，이기종동계농전잡초중사선출력초부집식물，위력오염농전토양적동계식물수복제공재료。통과토양충자고-금속사선법초보연구발현，동계농전잡초번루（Stellaria media）지상부분력함량접근초부집식물적림계치（100 mg·kg-1），단전운계수（TF）소우1，가능시력부집식물。위차，채용분재시험진행료진일보적농도제도감정。결과표명，수토양력함량적증가，번루근계생물량、지상부분생물량、주지장도、근계장도、항성계수급내성계수균수토양력함량적증가이하강，단번루근계급지상부분력함량정현저증가적추세。여대조상비，재토양력질량분수위25、50、75、100화125 mg·kg-1시，번루총생물량분별하강료17.31%、34.87%、44.79%、52.12%화59.32%，단각개처리균몰유표현출명현독해증상。토양력함량위75~125 mg·kg-1시，번루지상부분력함량균대우100 mg·kg-1，최대치위135.79 mg·kg-1，지상부분부집계수（BCF）대우1，단전운계수（TF）소우1。재토양력함량위100 mg·kg-1시，번루지상부분력제취량체도최대치，위87.42μg·plant-1。저사결과표명번루시일충력부집식물。수연번루적단주력제취솔교저，단번루구유분얼력강、번식력강、생장밀도대、내음성강등특점，인차괄용우동계농전력오염적수복。
To screen out more cadmium hyperaccumulators as phytoremediation materials, the winter farmland weeds were as the research objects in this study, using the soil seed bank-metal hyperaccumulator screening method to find out cadmium hyperaccumulators from the winter farmland weeds. And, it could provide the materials to remediate Cd-contaminated soil of farmland in winter. In a preliminary study, the soil seed bank-metal hyperaccumulator screening method was used to screen for Cd-hyperaccumulator. It found that the cadmium content in shoots of the winter farmland weedStellaria media closed to the critical value of Cd-hyperaccumulator (100 mg·kg-1), but translocation factor (TF) was less than 1, indicating that this plant might be a Cd-accumulator. In this study, we grewS. media in soil containing various concentrations of cadmium to further evaluate its cadmium accumulation characteristics. The results showed that the cadmium contents in roots and shoots ofS. media increased with the increase of cadmium concentration in soil, while the root biomass, shoot biomass, main branch length, root length, resistance coefficient and tolerance index and decreased. Compared with the control, when the dose of cadmium in soil were 25, 50, 75, 100 and 125 mg·kg-1, the total biomass of S. media decreased by 17.31%, 34.87%, 44.79%, 52.12% and 59.32%, but there were no obvious toxic symptoms in each treatment. The cadmium content in shoots ofS. media exceeded 100 mg·kg-1 when the dose of cadmium was 75~125 mg·kg-1 in soil, up to the maximum of 135.79 mg·kg-1, and the bioconcentration factor (BCF) of shoot was greater than 1 and the TF was less than 1. The cadmium extraction in shoots ofS. media got the maximum of 87.42μg·plant-1 at the dose of 100 mg·kg-1 cadmium in soil. Therefore,S. media is a Cd-accumulator. Although the cadmium extraction rate of each plat was low, but S. media has the characteristics of strong tillering ability, strong reproductive ability, and can growth in highly density, shade environment. So, S. media could be used to remediate Cd-contaminated soil of farmland in winter.
