摘要:
为在喀斯特石漠化生态恢复治理中科学选择抗旱植物材料提供依据,本文以贵阳花溪区附近石漠化区为例,利用快速叶绿素荧光动力学技术研究了干旱和复水对石生反叶扭口藓(Barbulafallax Hedw.)叶绿素含量和荧光特性变化的影响,探讨了石漠化干旱环境与石生藓类光合特征的关系。结果表明:反叶扭口藓随干旱胁迫的增加,叶绿素含量总体呈出先降低后升高的趋势;叶绿素荧光参数Fo、qN上升,Fm、Fv/Fm、Yield、ETR、qP都随干旱胁迫的加剧而下降;在胁迫时间较短复水后(24 h)叶绿素荧光参数(Fo、Fm、Fv/Fm、Yield、qP、qN)基本恢复到对照水平,超过24 h造成胁迫程度的加重则无法恢复到对照水平。
Abstract:
Guiyang city is located in the central Guizhou Province,at an average elevation of 1 100 m,annual average temperature 15.2 ℃ and annual average rainfall of 1 178 mm.The soil in Guiyang is predominately calcareous (accounting for 85 %),whose parent rocks are mainly dolomitic limestone and calcium dolomite. Its forest coverage is 5 %-15 %,the vegetation coverage is 10 %-90 %,the bare rock is 30 %-90 %, the land reclamation is 10 %-70 %,and the average rocky desertification is 36.79 % .Huaxi district in Guiyang is taken as an example for ecological restoration and treatment research,which provides the basis for scientific selection of drought-resistant plants for cultivation in karst rocky desertification areas.Chloro-phyll-fluorescence was measured by a handy PAM-2100 fluorometer in moss Barbulafallax Hedw.when drought and rehydration affected chlorophyll content and fluorescence under increased drought stress,the to-tal chlorophyll content first dropped ,and then increased gradually.F0 and qN of three kinds of mosses in-creased while the Fm ,Fv/Fm,Yield,ETR and qP decreased with drought stress.Fluorescence parameters after rehydration were restored to normal levels by mild to moderate stress,and severe stress is more diffi-cult to return to the control level.
下载: