中文摘要：

以附生西南树平藓（Homaliodendron montagneanum （C. Muell.） Fleisch）为供试材料，采用浸没培养法，研究Pb2＋、Zn2＋以及二者复合胁迫对西南树平藓的生长状况、叶绿素含量和叶绿素荧光特性的影响。结果表明：在Pb2＋、Zn2＋以及二者复合胁迫下，西南树平藓的健康状况不良，叶绿素含量显著降低，其中以Pb2＋胁迫下降最为明显，其次是Pb2＋Zn2＋的复合胁迫，而Zn2＋胁迫的影响较小；西南树平藓的最大光化学效率（Fv/Fm）、天线效率（Fv′/Fm′）、实际光化学效率（ΦPSⅡ）、光化学淬灭系数（qP）、光合电子传递速率（ETR）的下降程度与重金属浓度和胁迫时间存在明显的效应关系，随着重金属胁迫浓度增加和胁迫时间延长，上述各项指标下降幅度越明显；而随着胁迫时间的延长，低浓度时非光化学淬灭系数（NPQ）呈现先上升后下降的趋势，但在高浓度下NPQ持续下降；西南树平藓的叶绿素含量和叶绿素荧光参数对于Pb2＋、Zn2＋以及二者复合胁迫的响应存在差异，单一的Pb2＋胁迫和Pb2＋Zn2＋复合胁迫在低浓度时即对西南树平藓光合作用产生显著抑制作用，而Zn2＋胁迫在中浓度时才对西南树平藓光合作用产生显著抑制作用；叶绿素含量和叶绿素荧光参数的变化情况表明，Pb2＋、Zn2＋及其复合胁迫的毒性大小为Pb2＋＞Pb2＋Zn2＋复合＞Zn2＋。

英文摘要：

In this study, we used the method of submerged culture to detect the health status, chlorophyll contents and photosynthetic fluorescence parameters of epiphytic moss Homaliodendron montagneanum （C. Muell.） Fleisch under the pollution stress of Pb2＋, Zn2＋ and their combination. The results showed that chlorophyll contents decreased significantly when the moss were cultured under Pb2＋, Zn2＋ and combination of both, respectively, and the effect of Pb2＋ stress was greater than that of Zn2＋ stress. Pb2＋, Zn2＋ stress and Pb2＋Zn2＋ combination stress caused obvious decreases in maximal photochemical efficiency of PSII （Fv/Fm）, effective photochemical efficiency of PSII （Fv′/Fm′）, effective quantum yield of PSII （ФPSⅡ）, coefficient of photochemical quenching （qP） and acyclic electron transfer rate （ETR）. However, coefficients of nonphotochemical quenching （NPQ） increased initially and then decreased under low concentration stress while NPQ was continuously decreased under high concentration stress. Furthermore, the chlorophyll contents and the photosynthetic fluorescence parameters of H. montagneanum responded differently under the treatments of Pb2＋, Zn2＋ and their combination. The variations of chlorophyll contents and photosynthetic fluorescence parameters indicated that the influence of Pb2＋ stress on H. montagneanum was greater than that of Zn2＋ or Pd2＋Zn2＋ combination under the same concentrations.