蚯蚓对土壤中铜_镉生物有效性的影响_俞协治

After one mo nth , abov eg round ry eg r ass biomass wa s weig hed. Soil pH ( 2g soil in 10ml 0. 01 mo l / L CaCl2 ) w as tested using a Beckman pH m eter. Concentra tio ns o f Cu a nd Cd in r yeg rass w ere dete rmined by using a tomic absor ptio n spec tro pho tome tey ( A A S) af ter cinera tio n-dig estio n. Fractio ns o f the metal in soils w ere also tested using sequential ex traction procedures: ( 1) W ater -soluble Cu and Cd: ex tracted with deionized w ate r, with a wa ter: soil ra tio o f 10 1; ( 2) CaCl2-ex trac ta ble Cu and Cd: ex tracted with 0. 01mol / L Ca Cl2 , with a solutio n: soil ra tio of 10 1; ( 3) D T PA-ex tractable Cu a nd Cd: ex trac ted with D T P A, p H 7. 3, with a solutio n: so il ratio of 2 1. Cu and Cd br ough t into so lution w ere measured by A AS.
摘要: 以第 四纪红黏土 红壤和长江 冲积物形 成的高砂土 为供试土 壤 ,分别加入 3个浓度的 Cu2+ ( 100, 200, 400 mg /kg )或 Cd2+ ( 5, 10, 20 mg /kg ) 模拟 土壤 污染 ,设置 接种 蚯蚓 ( Pheretima sp. )处理 与不 加蚯蚓 对 照 ,并种植黑麦草 ( Lolium multif lorum ) ,研究蚯蚓活动对土壤中 Cu、 Cd生物有效性的影 响 ,以揭示 蚯蚓在 植物修复重金属污染土壤中的作用。结果表明: 蚯 蚓活动显著增加红壤中 D T PA 提取态 Cu的含量 ,只有在 浓度低于 200 mg /kg Cu的处理中 ,才 能增加 Ca Cl2提取态 Cu的含量 ,对 H2 O 提取态 Cu 影响甚微 ; 而对高 砂土上 Cu、 Cd 的各种形 态影响均不 显著 ; 除红壤中浓 度高于 400 mg /kg Cu 和 10 mg /kg Cd处 理外 ,蚯蚓 活动显著提高了两种土壤上黑麦草地上 部的生物量 ;接种蚯蚓后各种重金属处 理中黑麦草对 Cu的 吸收量 也显著增 加 ,而 Cd的吸收 量变化不大。蚯蚓可能通过提 高重金属的 生物有效性 而间接影响 植物对重 金属 的修复效率。 关键词: 蚯蚓 ;土壤 Cu、 Cd污染 ; 重金属生物有效性 ;植物修复
5期
ຫໍສະໝຸດ Baidu
俞协治等: 蚯蚓对土壤中铜、镉生物有效性的影响
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pot ex periment. Each soil wa s divided into sev en equal par ts of 6. 0 kg each and a mended r espectiv ely to contain 0, 100, 200, 400 mg Cu /kg and 5, 10 and 20 mg Cd /kg by adding a ppro pria te concentra tio ns o f CuSO4 and CdCl2. After tw o -mo nth incubation, metal-t reated soil sa mples w ere div ided into tw o g ro ups with 3 po ts fo r each gr oup as r eplicates ( 1 kg soil /po t ) . One g ro up receiv ed six ear thw o rms ( Pheretima sp. ) for each po t, the o th er g ro up did no t co ntain a ny ear th wo rms. All ear thwo r ms we re co llected fro m an unco nta minated soil in Na njing Ag ricultura l Univ ersity and had a mean fresh weig ht o f 0. 6g. Each po t w as added to 0. 3333g K H2 PO4 a nd 0. 3477g U rea as miner al nutrients a nd receiv ed 15 pre-g er minated ryeg rass seeds ( Lolium multif lorum ) . The po ts w ere put in g reenhouse a nd w ere incuba ted fo r o ne month.
Effect of earthworm on bio-availability of Cu and Cd in soils
Y U Xi e-Zhi1 , CHEN G Jie-M i n1, 2 ( 1. Col lege of Resources an d Environmental Sciences, N an jin g Ag ricul tu r-
Beneficial roles o f ea rthw o rms o n soil fer tility , nutrient cycling and plant g ro wth hav e been commo nly o bserv ed. Ea rthw o rms can influence me ta l mobility in soil thr ough burr owing and casting ac tiv ity. T he questio n a rises w hether ear th wo rm activity can actually inc rease me ta l bioav ailability a nd hence pro mo te the uptake by plants, o r whe the r ear thw o rms hav e a positiv e effect on phy to remediatio n. The o bjective o f this study w as to inv estig ate the effect of ear th wo rm o n the bioav ailability of Cu a nd Cd in so ils th ro ug h a pot ex periment.
al Universi ty , N anj in g 210095, China; 2. Col lege of Pop ulat ion , Resources an d Environmental Sciences , Shandong N ormal Universi ty , Ji′nan 250014, Ch ina ) . Act a E col og ica Sinica , 2003, 23( 5): 922～ 928. Abstract: Phy to remediatio n of heav y metals in contamina ted soil ha s bee n w idely accepted a s a cost-effectiv e, envir onmental-friendly tech no lo gy. M etal-accum ulating pla nts a re usually planted to r emov e metals fr om soils by concentra ting th em in the ha rv esta ble par ts, w hile the efficiency depends on the a mount o f abov eg round biomass and the bio av ailabililty of metals. Tho ugh additio n o f ch elating ag ents has been show n to incr ease me ta l bioav ailabililty and phy to remediation efficiency, it costs too much and sho w s env iro nmenta l risk.
It was fo und tha t ear thw o rm ac tiv ity sig nifica ntly decr eased the pH fo r the Red soil, a key chemical facto r affecting bioav ailability o f nut rient elements and heav y metals in soil, but had little effec t o n p H for the O r thic a quisols. Abov eg r ound bio ma ss o f the r yeg ra ss increased dr amatically fro m 33% to 96% in the presence of ea rthw or ms except fo r the tr eatments with 400 mg Cu /kg soil and 10 mg Cd /kg soil. Ear thwo r m activity markedly inc reased concentra tio ns o f D T PA-ex tracta ble Cu and wa ter-so luble Cd fo r the red soil, ho w ev er , it did no t affect three fr actio ns of Cu or Cd for th e O r thic a quisols . To tal uptake of Cu by the r yeg rass wa s e nhanced by ea rthw o rm activ ity in the two soils, while no sig nifica nt diffe rence was o bserv ed in co ncentra tio n o f Cu o r Cd in pla nt tissue be tween tr eatments with and without ea rthw or m additio n.
第 23卷第 5期 2003年 5月
生 态 学 报 ACT A ECOLO GICA SINICA
V o l. 23, N o. 5 M ay , 2003
蚯蚓对土壤中铜、镉生物有效性的影响
俞协治 1 , 成杰民 1, 2*
( 1. 南京农业大学资源与环境科学学院 ,南京 210095; 2. 山东师范大学人口、资源与环境学院 ,济南 250014)
Tw o soils, r ed soil fr om Jiang x i Province a nd O r thic aquisols fr om Jiangsu Pr ovince , w er e used in the
基金项目: 国家自然科学基金资助项目 ( 40271068) 收稿日期: 2002-05-28; 修订日期: 2002-10-16 作者简介: 俞协治 ( 1977～ ) ,男 ,江苏无锡人 ,硕士生 ,主要从事环境化学污染治理研究。 * 通信作者 Aut hor fo r co rrespond ence, E-mail: jmchengcn@ yah oo. com. cn. Foundation i tem: N ational N atu ral Sci ence Foundati on of Ch ina ( Grant N o. 40271068) Received date: 2002-05-28; Accepted date: 2002-10-16 Biography: Y U X ie-Zhi , M as ter candi date, mai nly engaged in research abou t chemical poll uti on cont rol of envi ron men t.