欢迎访问《应用生态学报》官方网站,今天是 分享到:

应用生态学报

• 研究报告 • 上一篇    下一篇

四种北方阔叶树种苗木对土壤镉胁迫的生长反应与抗性比较

李亚藏;王庆成;马树华   

  1. 东北林业大学林学院,哈尔滨 150040
  • 收稿日期:2004-05-13 修回日期:2003-10-02 出版日期:2005-04-18

Growth responses of four northern broadleaved tree species to soil Cd stress

LI Yacang,WANG Qingcheng,MA Shuhua   

  1. College of Forestry,Northeast Forestry University,Harbin 150040,China
  • Received:2004-05-13 Revised:2003-10-02 Online:2005-04-18

摘要: 采用盆栽方法,研究4种北方阔叶树种茶条槭、山梨、五角槭和山荆子一年生苗木对土壤镉胁迫的生长反应和抗性.采用土壤和风化砂混合物作为栽培基质,设计5种土壤镉浓度梯度处理(对照、10、50、100、200 mg ·kg-1).结果表明,低浓度处理(≤50 mg·kg-1)刺激各树种苗木的地径、树高生长,其中茶条槭在10 mg·kg-1处理下地径和苗高增加幅度最大,分别为对照的135.8%和146.0%;随着镉处理浓度的增加,地上部生长量下降,茶条槭在最高浓度处理下,生长量降低最大,地径和苗高仅分别为对照的24.1%和28.0%.叶片和新枝生物量变化存在较大种间差异,茶条槭和山梨在低浓度处理时总体上表现增加;山荆子新枝生物量增加,叶生物量减少;五角槭表现一致减少.最高浓度处理时,叶和新枝生物量受影响最大的是茶条槭,分别为对照的4.6%和7.3%;其次为五角槭,分别为对照的5.7%和7.9%;山梨和山荆子受影响的幅度相对较小.新根生物量除山梨外,其它3个树种苗木的生物量表现一致下降,其中下降幅度以茶条槭最大,最高浓度处理仅为对照的2.3%.山梨在低浓度处理下,新根生物量有所增加,分别为对照的125.5%和117.1%.茶条槭和山梨的苗木在低浓度处理下,总生物量增加幅度提高;高浓度处理时,所有树种苗木的生物量增加幅度均显著降低.最高浓度处理时,茶条槭、山荆子、五角槭和山梨苗木生物量增加幅度分别为对照的13.7%、27.2%、36.4和40.1%.采用隶属函数对上述指标进行综合分析, 得出4个树种对土壤镉污染的抗性顺序为山荆子>茶条槭>山梨>五角槭.最高浓度处理下,山 梨对土壤中的镉具有最强的富集能力,其根茎叶部镉的富集系数明显高于其它3个树种,山 荆子根、茎部位富集系数也较高.

关键词: 铜, 黑土, 棕壤, 吸附作用, 热力学, 化学动力学

Abstract: In this paper,the gradient (0,10,50,100,200 mg·kg-1) of soil Cd concentrations was established by mixing CdCl2 with soil and sand,and the growth responses of four northern broadleaved tree species Acer ginnala Pyrus ussuriensis,Acer mono and Malus baccatato soil Cd contamination were studied by growing their seedlings in pots in greenhouse. The results revealed that the seedling growth of all test species was enhanced under lower soil Cd concentrations (≤50 mg·kg-1),and Acer ginnala had the strongest response under 10 mg·kg-1 treatment,with 135.8% and 146.0% increment of collar and height growth,respectively,in comparing with the control.But,the growth of aboveground part decreased with increasing soil Cd,and the collar and height growth of A.ginnala under the highest Cd concentration was only 24.1% and 28.0% of the control,respectively.Under lower Cd concentrations,an increase of foliage and new shoot growth was found in A.ginnala and P.ussuriensis,the biomass of new shoots increased but that of foliage decreased in M.baccata,and both foliage and new shoot decreased in A.mono.Under the highest Cd concentration,A.ginnala had the greatest decrease of foliage and new shoot biomass,being 4.6% and 7.3% of the control,respectively,while P.ussuriensis and M.baccata had a relatively less decrease.The biomass increase of new roots declined with increasing Cd concentration for all tree species except P.ussuriensis,and the least increase was A.ginnala,only 2.3% of the control.The new root biomass of P.ussuriensis was 125.5% and 117.1% of the control at 10 mg and 20 mg·kg-1,respectively.The total biomass increment of A.ginnala and P.ussuriensis seedlings was greater than that of the control under lower Cd concentrations,while an obvious decrease was found for all tree species under higher Cd concentrations.Under the highest Cd concentration,the total biomass of A.ginnala,M.baccata,A.mono and P.ussuriensis was 13.7%,27.2%,36.4 and 40.1% of the control,respectively.Subordinate function analysis suggested that the tolerance of test tree species to soil Cd contamination was in order of M.baccata > A.ginnala > P.ussuriensis > A.mono.Analysis of Cd concentration in plant tissues demonstrated that P.ussuriensis had the highest Cd enrichment coefficient for its root,shoot and foliage,and M.baccata also had a higher Cd enrichment in its root and shoot.

Key words: Cu, Phaeozem, Burozem, Adsorption, Thermodynamics, Chemical kinetics