Chlorophyll content and fluorescence parameters of epilithic mosses in habitats of different rocky-desertification grades

PDF HTML阅读 XML下载 导出引用 引用提醒 不同等级石漠化生境下石生苔藓叶绿素含量和叶绿素荧光参数研究 DOI: 10.5846/stxb202207192061 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31960262，32260313）；贵州省科技计划项目（2019年度学术新苗培养及创新探索专项项目）；贵中医博士启动（2020）44 Chlorophyll content and fluorescence parameters of epilithic mosses in habitats different rocky-desertification grades Author: Affiliation: Fund Project: National Natural Science Foundation China (31960262、32260313); Technology Project Guizhou Province (2019 Special for Academic Seedling Cultivation Innovation Exploration); Started by Doctor Medicine (2020)44 摘要 | 图/表 访问统计 参考文献 相似文献 引证文献 资源附件 文章评论 摘要:叶绿素含量和叶绿素荧光参数可以反映叶绿体状态及光合作用效率，可用于探讨植物对环境的适应能力和响应机制。选择贵州省毕节市撒拉溪石漠化治理示范区，研究了区内28个不同等级石漠化（无、潜在、轻度、中度、重度石漠化）样地中所采集的168份石生苔藓植物标本，探讨了其相对叶绿素含量（SPAD值）和叶绿素荧光参数对不同喀斯特石漠化生境的响应。结果表明：（1）石生苔藓SPAD值、叶绿素荧光参数受多种环境因子的综合影响，其中石漠化等级、大气温度、郁闭度、坡向的影响较为显著。（2）相较于低等级石漠化和阴坡生境，中高等级石漠化和阳坡的石生苔藓SPAD值和除非光化学淬灭系数（NPQ）和非调节性能量耗散（ФNO）之外的叶绿素荧光参数均降低，可能由于在石漠化生态系统逆向演替后期，石生苔藓植物的叶绿素含量降低，PSⅡ反应中心活性受到影响，PSⅡ电子传递受阻，植物体通过增加热耗散和启动非调节性机制进行自我保护。（3）3种优势石生苔藓植物中，穗枝赤齿藓（Erythrodontium julaceum）的SPAD值显著低于圆枝粗枝藓（Gollania tereticaulis）和密毛细羽藓（Cyrto-hypnum gratum），但各优势种的SPAD值在不同等级石漠化生境下并没有显著变化，表明石生苔藓叶绿素含量对石漠化生境恶化的响应可能是通过物种选择而非同一物种的调节适应来实现的。（4）随着石漠化程度的加深，圆枝粗枝藓除NPQ上升以外，其他叶绿素荧光参数均较高且稳定；穗枝赤齿藓和密毛细羽藓的变化相对显著，在较高等级石漠化生境中均存在光抑制现象。研究结果可为石漠化生态系统及其植被恢复机理研究提供一定的数据支撑和理论依据。 Abstract:Chlorophyll can reflect the chloroplast state photosynthesis efficiency, be used to study adaptability response mechanism plants environment. In this study, Salaxi Rocky Desertification Control Demonstration Area Bijie City, was selected as research area. total 168 moss specimens were collected explore responses their relative chlorophyll (SPAD value) (none, potential, light, moderate severe). The results showed that:(1) SPAD value, comprehensively influenced many environmental factors, among which effects rocky desertification grade, slope direction, canopy density, atmospheric temperature more significant. (2) Compared with lower shady slope, value except non-photochemical quenching coefficient (NPQ) non-regulated energy dissipation (ФNO) decreased medium high-grade sunny slopes. It might hint that, later stage degradation, decreased, activity reaction centers affected, PSⅡ electron transport blocked, self-protection function meantime activated thorough a non-regulatory well increasing heat dissipation. (3) Among three dominant mosses, Erythrodontium julaceum had significant values than Gollania tereticaulis Cyrto-hypnum gratum. For each moss, there no change grades. indicated that habitat degradation through species selection rather adjustment adaptation same species. (4) With habitat, G. did not significantly increase NPQ, indicating kept relatively high stable efficiencies areas. Both E. C. gratum changes photo-inhibition occurred higher-level habitats, initiated protective mechanisms. other two species, has larger biomass, covering large area rock surface some plots. addition stronger photosynthetic capacity, it is adaptive habitats. Therefore, have potential on bare-rock restoration regions. provide certain data support theoretical basis ecosystem its vegetation