【作者】 李腊梅；

【导师】 商宏利；

【作者基本信息】 四川师范大学 ， 环境科学， 2010， 硕士

【摘要】 本研究以吊兰为材料,利用水培和土培法研究了重金属Pb²⁺、Cd²⁺及其复合胁迫对吊兰幼苗生长及生理的影响,探讨吊兰对重金属Pb²⁺、Cd²⁺的耐性以及Pb²⁺、Cd²⁺之间的交互作用,为将该植物应用于Pb²⁺、Cd²⁺污染土壤的修复提供科学理论依据。主要实验结果如下:1、土培条件下,Pb²⁺不大于1000mg·kg^-1和0.3 mgkg^-1 Cd²⁺胁迫可以轻微促进吊兰的生长,总生物量、地上生物量、株高、叶片数、叶长都要比对照有所升高,且差异显著。随着Pb²⁺、Cd²⁺及复合浓度的升高,吊兰生长受到严重抑制。Pb²⁺、Cd²⁺及其复合胁迫对吊兰地下生物量、叶宽、根长影响不显著,复合胁迫对吊兰的幼苗生长影响大于Pb²⁺、Cd²⁺单一胁迫。水培条件下对吊兰生长表现出抑制作用的浓度,土培条件下则表现出明显的刺激作用,表明土壤对Pb²⁺、Cd²⁺污染有很强的缓冲作用。且Pb²⁺、Cd²⁺之间能够表现出拮抗和协同作用。2、水培条件下,Pb²⁺的的处理浓度不大于800mgL-1且镉的浓度为0.3mgL-1时可以促进吊兰生长,总生物量、地上生物量、株高、叶片数、叶长都要大于对照。当Pb²⁺、Cd²⁺及复合浓度增大时,生长受到抑制。与土培相同,Pb²⁺、Cd²⁺及其复合胁迫对吊兰地下生物量、叶宽、影响不显著,但对根长影响显著。复合胁迫对吊兰的幼苗生长影响大于Pb²⁺、Cd²⁺单一胁迫。Pb²⁺、Cd²⁺之间能够表现出拮抗和协同作用。但不论土培和水培,Pb²⁺、Cd²⁺之间相互作用是与多种因素有关,表现的极为复杂,不仅仅是单纯的加和、拮抗或协同作用。3、不论土培或水培条件下,Pb²⁺、Cd²⁺单一和复合处理叶绿素的含量都表现为先上升后下降的趋势,土培条件下300mg·kg^-1 Pb²⁺和5 mgkg^-1 Cd²⁺胁迫对吊兰叶绿素含量有促进作用,但水培条件下却变为100mg·kg^-1 Pb²⁺和0.3 mgkg^-1 Cd²⁺胁迫对叶绿素有促进作用。随着Pb²⁺、Cd²⁺及其复合浓度的升高,吊兰叶绿素含量呈逐渐下降趋势,复合胁迫对叶绿素含量影响较大。吊兰幼苗MDA含量会随着Pb²⁺、Cd²⁺单一和复合浓度的升高逐渐升高,与Pb²⁺、Cd²⁺浓度呈正相关性。更多还原

【Abstract】 ABSTRACT: This paper studied the growth and physiological effects of Chlorophytum comosum under different concentration of single Pb, Cd and Cd-Pb compounds by the methods of soil culture and water culture, investigated how Chlorophytum comosum bear the pollution of Pb and Cd and the interaction between Pb and Cd, which offered some evidence on alleviating the damage caused by Pb and Cd .The main conclusions are as follows:1.With soil culture experiment, low concentration of Pb²⁺ (≤1000mg·kg^-1) and Cd²⁺ (0.3 mg·kg^-1) can promot the growth of Chlorophytum comosum slightly. Total biomass,Overground biomass ,Plant height, Number of leaf and Length of leaf increased with the control ,and the difference was significant.With the increasing concentration of single Pb²⁺、Cd²⁺ and Pb²⁺-Cd²⁺ compounds ,the growth of Chlorophytum comosum has been inhibited severely.Single Pb²⁺ and Cd²⁺ and Pb²⁺-Cd²⁺compounds has not great effects on the underground biomass、Leaf width and length of root.The poisoning effect of Pb²⁺-Cd²⁺ on the growth of Chlorophytum comosum was stronger than single Pb²⁺ and Cd²⁺ stress.The concentration of Pb²⁺and Cd²⁺ would inhibite the growth of Chlorophytum comosum when cultivated via water culture,while promoted its growth when cultivated via soil culture,so we could conclude soil amortized the damage of Pb²⁺and Cd²⁺ . The interactive effect of Cd²⁺ and Pb²⁺ was antagonistic and synergistic. 2.With water culture experiment, under concentration of Pb²⁺ (≤800 mg·L^-1) and Cd²⁺ (0.3 mg·L^-1), the growth of Chlorophytum comosum was promoted slightly.Total biomass ,Overground biomass ,Plant height, Number of leaf and Length of leaf increased with the control .With the increasing concentration of single Pb²⁺,Cd²⁺ and Pb²⁺-Cd²⁺ compounds ,the growth of Chlorophytum comosum has been inhibited.Same as soil culture experiment, Pb²⁺ and Cd²⁺ and Pb²⁺-Cd²⁺compounds has not great effects on the underground biomass,leaf width ,but has great effects on length of root.The effect of Pb²⁺-Cd²⁺ compound on the growth of Chlorophytum comosum was stronger than single Pb²⁺and Cd²⁺ stress. The interactive effect of Cd²⁺ and Pb²⁺ was antagonistic and synergistic.But no matter cultivated in soil or in water, the interactive effect of Cd²⁺ and Pb²⁺ was complicated,not simply additive,antagonistic and synergistic ,but also related with many factors.3.No matter cultivated in soil or in water,under single Pb²⁺、Cd²⁺ and Pb²⁺-Cd²⁺ compounds treatment, the contents of chlorophyll rised and then declind. When cultivated in soil, under concentration of Pb²⁺ (300mg·kg^-1) and Cd²⁺ (5 mg·kg^-1),the contents of chlorophyll increased slifhtly. But cultivated in water , under concentration of Pb²⁺ （100 mg·L-1） and Cd²⁺ （0.3mg·L-1）,the contents of chlorophyll increased .With the increasing concentration of single Pb²⁺、Cd²⁺ and Pb²⁺-Cd²⁺ compounds ,the chlorophyll concent was gradually declined . Pb²⁺-Cd²⁺ compounds had stronger effect on chlorophyll content.MDA gradually increased with the increasing concentration of Pb²⁺,Cd²⁺ and Pb²⁺-Cd²⁺ compounds,and had positive correlation with Pb²⁺and Cd²⁺ concentration.更多还原