通过盆栽试验研究了不同镉浓度处理下旱莲草的镉富集特性。结果表明：随土壤镉浓度的增加，旱莲草生物量、株高、根长、叶绿素SPAD值、抗性系数都呈下降趋势，而根系和地上部镉含量呈增加的趋势。在土壤镉浓度为大于50 mg/kg时，旱莲草地上部分镉含量均大于镉超富集植物临界值(100 mg/kg)。在不同的土壤镉浓度处理下，旱莲草根系和地上部分镉富集系数(BCF)大于1，但转运系数(TF)小于1。旱莲草地上部分镉积累量最大值为38.06 μg/株(土壤镉浓度为25 mg/kg)。小区试验研究表明，在土壤镉浓度为2.04~2.89 mg/kg时，旱莲草地上部分镉积累量为0.393~0.435 mg/m2。因此，旱莲草是一种镉富集植物，具有较好的镉富集能力，可用于农田镉污染土壤修复。
In this study, we grew this plant in soil containing various concentrations of cadmium to further evaluate its cadmium accumulation characteristics.The results showed that the biomass, height, root length, chlorophyll SPAD value and the resistance coefficient decreased with the increase of cadmium concentration in soil, while the cadmium contents in root and shoot of E.prostrata increased.The cadmium contents in shoot and root of E.prostrata exceeded 100 mg/kg when the dose of cadmium was more than 50 mg/kg in soil, and the BCFs of root and shoot were greater than 1 and the TF was less than 1.The maximum of cadmium accumulation in shoot of E.prostrata was 38.06 μg/plant (The dose of cadmium was 25 mg/kg in soil). In the plot experiment, when cadmium concentrations of soil were 2.04-2.89 mg/kg, the cadmium accumulations in shoot of E.prostrata were 0.393-0.435 mg/m2.Therefore, Eclipta prostrata L.is a Cd-accumulator plant with better capability and could be used to remediate Cd-contaminated farmland.
[1] 赵修华,任之光,祖元刚,等.入侵植物假苍耳对镉的富集特征[J].森林工程,2010,26(4):39-43.
[2] 李玉浸.集约化农业的环境问题与对策[M].北京:中国农业科技出版社,2001.
[3] 韦朝阳,陈同斌.重金属超富集植物及植物修复技术研究进展[J].生态学报,2001,21(7):1196-1203.
[4] 何启贤.镉超富集植物筛选研究进展[J].环境保护与循环经济,2013,33(1):46-49.
[5] 孙铁珩,李培军,周启星.土壤污染形成机理与修复技术[M].北京:科学出版社,2005.
[6] Datta R,Sarkar D.Effective integration of soil chemistry and plant molecular biology in phytoremediation of metals [J].Environmental Geosciences,2004,11(2):53-63.
[7] 鲍 桐,廉梅花,孙丽娜,等.重金属污染土壤植物修复研究进展[J].生态环境,2008,17(2):858-865.
[8] 郭水良,李扬汉.杂草的基本特点及其在丰富栽培地生物多样性中的作用[J].自然资源,1996(3):48-53.
[9] 陈 欣,唐建军,赵惠明.农业生态系统中杂草资源的可持续利用[J].自然资源学报,2003,18(3):340-346.
[10] Wei S H,Zhou Q X,Wang X,et al.A newly-discovered Cd-hyperaccumulator Solanum nigrum L.[J].Chinese Science Bulletin,2005,50(1):33-38.
[11] 聂发辉.镉超富集植物商陆及其富集效应[J].生态环境,2006,15(2):303-306.
[12] 李玉双,孙丽娜,孙铁珩,等.超富集植物叶用红菾菜(Beta vulgaris var.cicla L.)及其对Cd的富集特征[J].农业环境科学学报,2007,26(4):1386-1389.
[13] 杨 勇,江荣风,李花粉,等.土壤容重改变对锌/镉超累积植物遏兰菜根系特征及吸镉的影响[J].环境科学,2010,31 (12):3043-3049.
[14] 孙约兵,周启星,任丽萍.镉超富集植物球果蔊菜对镉-砷复合污染的反应及其吸收积累特征[J].环境科学,2007,28(6):1355-1360.
[15] Wei S,Clark G,Doronila A I, et al. Cd hyperaccumulative characteristics of Australia ecotype Solanum nigrum L.and its implication in screening hyperaccumulator [J].International Journal of Phytoremediation,2013,15(3):199-205.
[16] 俞慧娜,刘闻川,张晓燕,等.9种杂草植物相对铝耐性的特征分析[J].草业科学,2009,26(11):130-137.
[17] 周 楠,刘 鹏,徐根娣,等.四种常见杂草根系及根边缘细胞对铝胁迫的响应[J].生态学报,2009,29(12):6512-6518.
[18] 鲍士旦.土壤农化分析[M].3版.北京:中国农业出版社,2000.
[19] 赵杨迪,潘远智,刘碧英,等.Cd、Pb单一及复合污染对花叶冷水花生长的影响及其积累特性研究 [J].农业环境科学学报,2012,31(1):48-53.
[20] Zhang X F,Xia H P,Li Z A, et al. Identification of a new potential Cd-hyperaccumulator Solanum photeinocarpum by soil seed bank-metal concentration gradient method [J].Journal of Hazardous Materials,2011,189(1-2):414-419.
[21] Rastmanesh F,Moore F,Keshavarzi B.Speciation and phytoavailability of heavy metals in contaminated soils in Sarcheshmeh area,Kerman Province,Iran [J].Bulletin of Environmental Contamination and Toxicology,2010,85(5):515-519.
[22] Zhang S,Lin H,Deng L, et al. Camium tolerance and accumulation characteristics of Siegesbeckia orentalis L.[J].Ecological Engineering,2013,51:133-139.
[23] Brooks R R,Lee J,Reeves R D, et al. Detection of nickeliferous rocks by analysis of herbarium specimens of indicator plants [J].Journal of Geochemical Exploration,1977,7:49-57.
[24] Brooks R R.Plants that hyperaccumulate heavy metals:Their role in phytoremediation,microbiology,archaeology,mineral exploration and phytomining [M].Oxford,UK:CAB International,1998.
[25] 侯伶龙,黄 荣,周丽蓉,等.鱼腥草对土壤中镉的富集及根系微生物的促进作用[J].生态环境学报,2010,19(4):817-821.
[26] Clabeaux B L,Navarro D A G,Aga D S, et al. Cd Tolerance and accumulation in the aquatic macrophyte, Chara australis :potential use for charophytes in phytoremediation [J].Environmental Science & Technology,2011,45(12),5332-5338.
