【作者】 李亚藏；

【导师】 王庆成； 张彦东；

【作者基本信息】 东北林业大学 ， 森林培育， 2004， 硕士

【摘要】 本文采用温室盆栽的方法研究了茶条槭（Acer ginnala Maxim）、山梨（Pyrus ussuriensis Maxim）、五角槭（Acer mono Maxim）和山荆子（Malus bacata Borkh）一年生幼苗对土壤重金属（镉和铅）胁迫的生理生化和生长反应，分析了重金属在植物体内的分配和富集状况，并对四树种的重金属抗性进行了综合评定。每树种设置的浓度梯度，镉为10、50、100、200 mg．kg^-1(以Cd²⁺计)，铅为100、500、1000、2000 mg．kg^-1(以pb²⁺计)，同时设置对照（分别表示为CK、Cd10、Cd50、Cd100、Cd200、Pb100、Pb500、Pb1000、Pb2000）。研究结果如下： 1 镉铅污染对四树种苗木光合作用的影响。 随着土壤中镉铅浓度的增加，四树种叶片的叶绿素含量降低，最高浓度处理（Cd200、Pb2000）与对照相比均达显著水平（P＜0.05）。其中五角槭最为明显，Cd200和Pb2000处理分别比对照降低65.3％和49.2％，山梨（59.8％、31.7％）和茶条槭（54.9％、23.9％）居中，山荆子降幅最小（22.8％、12.0％）。叶绿素降低的同时，植物叶片的净光合速率也发生了变化。五角槭的光合速率随镉处理浓度的增加而降低，Cd200处理与对照相比降低81.1％；其它三树种先升后降，山荆子变化较大，其次为茶条槭，山梨变化最小；随铅浓度的增加，山梨的净光合速率持续下降，Pb2000处理与对照相比降低49.9％；其它三树种先升后降，其中五角槭最为敏感，Pb100处理时与对照相比高出124.0％，Pb2000处理略低于对照1.4％。镉铅胁迫下，多数树种的叶绿素荧光参数F_v／F_m、Φ_PSⅡ、qP和qNP有不同程度的下降，但变化幅度相对较小。 2 镉铅污染对四树种苗木叶片膜脂过氧化和保护酶活性的影响。 随土壤中重金属浓度的增加四树种叶片的相对电导率上升，且种间差异明显。镉胁迫下，五角槭最为敏感，Cd200处理比对照增加了5.9％，其次为山荆子（5.1％）、和山梨（4.9％），茶条槭受影响最小（4.6％）；Pb2000处理下，变化最大的仍为五角槭（5.7％），其次为山梨（5.2％）和茶条槭（3.8％），山荆子变化最小（3.3％）。四树种苗木叶片的SOD活性随镉铅浓度的增加先升后降，最高浓度镉处理（Cd200），山梨（26.2％）和五角槭（20.2％）的降幅大于山荆子（15.0％）和茶条槭（11.6％）；Pb2000处理下，山梨和五角槭分别略低于对照2.8％和3.1％，山荆子和茶条槭的SOD活性仍分别高于对照3.2％和5.3％。POD活性随土壤中镉铅浓度的增加持续上升。山梨变化最大，Cd200和Pb2000处理时分别高出对照177.8％和88.9％，五角槭（150.0％、75.0％）和茶条槭（122.2％、100％）居中，山荆子变化最小（53.9%、38.5%）。3锡铅污染对四树种苗木生长及生物量的影响。 从植物外观来看，重金属胁迫下叶片出现失绿症状，以含锡处理最为明显，树种中以茶条械和五角械最为突出。低浓度锡铅刺激多数树种地径、苗高、新枝和叶片的生长，随着锡铅浓度的增加，各指标下降，其中五角械受影响最大，其它三树种差异不明显。锡铅对地下部根系的毒害先于地上部分，茶条械和山荆子的新根生物量随土壤中锅铅浓度的增加而下降，最高浓度处理（CdZoo、Pb加oo）分别降为对照的2.3%、73.4%和18.7%、45.25%:其它两树种的新根生物量因重金属种类而不同，在锡胁迫下，山梨的新根生物量先升后降，五角械持续下降;在铅胁迫下，五角械的各处理均高于对照，山梨均低于对照。4锡铅在四树种苗木体内的分配和富集。 在Cd200处理下，山梨对锡迁移能力最强，能将根系所吸收福的巧.95%迁移到茎部，15.80%迁移到叶片，山荆子和五角械分别将15.94%和6.46%的锡迁移到地上部分，茶条械迁移能力最差，迁移到茎和叶的仅占1.94%和0.59%。四树种吸收的锡在各器官的累积量均为根>茎>叶。Pb2000处理下，山荆子相对迁移能力较强，根系吸收的铅10.22%迁移到茎部，8.34%迁移到叶部，其它三树种差异不明显。各器官铅累积量的排列顺序，除山梨的叶部铅含量大于茎外，其它三树种均为根>茎>叶。最高浓度（Cd200，PbZooo）处理下，山梨对锡铅的富集能力最强，各器官的富集系数均明显高于其它三者。比较各树种茎部对锡铅的富集系数为山梨>山荆子>五角械>茶条械。5四树种抗性的综合评定。 采用隶属函数法对四树种重金属抗性进行综合评定。结果显示，四树种对土壤锡的抗性为山荆子>茶条械>山梨>五角械;对铅的抗性为茶条械>山梨>山荆子>五角械。更多还原

【Abstract】 The reaction of the physiological and biochemical and growth of Acer ginnala Maxim, Pyrus ussuriensis, Acer mono Maxim and Malus bacata Borkh were studied under thestress of heavy metals (Cd2+ and Pb2+ ) in the soil by the seedlings in pots in greenhouse, the distribution and accumulation of heavy metals were analyzed in the four species and the resistance of the four species to heavy metals was evaluated. Every species was designed under different concentration gradient, Cd2+: 10 50 100 200mg kg-1(pure Cd2+), Pb2+ 100, 500 , 1000 2000 mg kg -1 (pure Pb2+), simultaneity CK was designed (showed CK Cd10 Cd50 Cd100 Cd200 Pb100 Pb500, Pb1000 Pb2000 in text). The results were as follows:1 The effects of Cd2+ and Pb2+ on photosynthesis of the seedlings With enhancing of the concentration of the Cd2+ and Pb2+, chlorophyll content in leaves of four tree species declined, It was achieved significant level in contrast with the hig -hest concentration treatment(Cd200, Pb2000) and CK ( P<0.05 ) . Acer mono Maxim was the most distinct, Pyrus ussuriensis Maxim and Acer ginnala Maxim were at second place, Malus bacata Borkh was the least. With the decline of chlorophyll, pure photosynthetic rate of plant leaves change. With Cd2+ concentration enhanced, photosynthetic rate of Acer mono Maxim decline, other three tree species first increase then descend, the variety of Malus bacata Borkh was the most, followed by Malus bac -ata Borkh, Pyrus ussuriensis Maxim was the least; pure photosynthetic rate of Pyrus ussuriensis Maxim continually decrease, with enhancing of the Pb2* concentration, that of other three tree species were first raised then decreased. Under the stress ofCd2* an -d Pb2+, chlorophyll fluorescence parameters Fv/Fm psII qP and qNP of most treespecies differently decreased, but variety was relative less.2 The effects of Cd2+ and Pb2+ on the cell membrane lipid peroxidation and theactivity of protectiase of the seedlingsRelative conductivity rate of four tree species leaves enhanced with increase of heavy metals and the difference among tree species was significant. Under the stress of Cd2+, Acer mono Maxim was the most sensitive, followed by Pyrus ussuriensis Maxim and Malus bacata Borkh, Acer ginnala Maxim was least; Under the stress of Pb2+, the variety of Acer mono Maxim was most, followed by Malus bacata Borkh and Acer gin -nala Maxim, the variety of Malus bacata Borkh was least. The activity of SOD offour tree species seedlings first enhanced then decreased with the enhancing of the concentration of Cd2+ and Pb2+, while under the highest concentration treatment (Cd200 Pb2000) , the decreasing degree was Pyrus ussuriensis Maxim and Acer mono Maxim >Acer ginnala Maxim and Malus bacata Bork. POD activity raised conti -nually with the increasing of Cd2* and Pb2"1" concentration. The variety of Pyrus ussuriensis Maxi -m was maximal, followed by Acer ginnala Maxim and Acer mono Maxim, the variety of Malus bacata Borkh was minimal.3 The effects of Cd2+ and Pb2+ pollution on growth and biomass of the seedlings From the appearances of plant, leaves appeared chlorosis symptom under the stress of heavy metals, Cd2+ treatment was the most obvious, the symptoms of Acer ginnala Ma -xim and Acer mono Maxim were the most outstanding among four tree species. The lo -wer concentration of Cd2+ and Pb2+ can stimulate the growth of base diameters, seedli -ng heights, new branches and leaves of most tree species. With the enhancing of Cd2+ and Pb2+ concentration, each indexes decreased, thereinto, the effect on Acer mono Ma -xim was maximal, while the effect on other three tree species were insignificant. The poison of Cd2+ and Pb2+ on underground roots was ahead of that on the overground, the new root growth quantity of Acer ginnala Maxim and Malus bacata Borkh decreased with the Cd2+ and Pb2+ concentration increased; the new root growth quantityof other t -wo tree species was different under different heavy metals treatments. Under the stress of Cd2+, the new root growth quantity of Pyrus ussuriensis Maxim fi更多还原