---

作 者 ：衣艳君,李芳柏,刘家尧*

期 刊 ：生态学报 2008年 28卷 11期 页码：5437~5444

关键词：尖叶走灯藓；重金属；叶绿素荧光；叶绿素含量；

Keywords:Plagiomnium cuspidatum (Hedw.) T.Kop., heavy metal, chlorophyll fluorescence, content of chlorophyll,

摘 要 ：利用快速叶绿素荧光动力学技术研究了Cu2+、Zn2+、Cd2+、Pb2+四种重金属离子复合污染下尖叶走灯藓Plagiomnium cuspidatum (Hedw.) T.Kop. 叶绿素荧光动力学以及叶绿素含量的变化。结果显示，重金属胁迫导致尖叶走灯藓PSII反应中心的最大光化学效率(Fv/Fm)、光合机构电子传递的量子产额(ETo/ABS)、捕获的激子将电子传递到电子传递链中超过QA的其它电子受体的概率(ETo/TRo)、单位叶面积的反应中心的数量(RC/CSo)降低。重金属胁迫也显著降低尖叶走灯藓植物体叶绿素a、叶绿素b、总叶绿素含量以及Chla/b的值，降低的程度与重金属浓度和胁迫时间有关。尖叶走灯藓可以耐受10μmol/L浓度的复合重金属污染，在10μmol/L浓度范围内，尖叶走灯藓PSII最大光化学效率Fv/Fm、单位面积有活性反应中心的数目RC/CSO、捕获的激子将电子传递到超过QA的其它电子受体的概率ETO/TRO以及用于电子传递的量子产额ETO/ABS等与对照相比均无明显变化，表明在此浓度范围内，重金属不会对尖叶走灯藓的光合器官造成伤害。50μmol/L和100μmol/L浓度的重金属则造成光合系统的不可逆损伤。

Abstract:Chlorophyll-fluorescence were measured by a handy PEA fluorometer in moss Plagiomnium cuspidatum (Hedw.) T.Kop. in response to a mixture heavy metal cations of Cu2+，Zn2+, Cd2+ and Pb2+ at concentrations of 0, 1, 5, 10, 50 and 100μmol/L respectively. Exposure in a mixture heavy metal solution 10-day period resulted in a decline of chlorophyll fluorescence and content of chlorophyll. Heavy metals used within 10μmol/L，a little change of all the analyzed values of Fv/Fm、ETo/ABS、ETo/TRo and RC/CSo was observed compare with controls, but a dramatic decrease occurred when the metal concentration increased to 50 and 100μmol/L.The result indicated that the photosynthetic apparatus of the moss Plagiomnium cuspidatum was not badly damaged when the mixed-heavy metal solution became lower than 10μmol/L concentrations, but the damage was not reversible up to 50 or 100μmol/L.

---