河西荒漠区石下生蓝藻叶绿素荧光参数的日变化  

Daily variations in chlorophyll fluorescence parameters of hypolithic cyanobacteria in desert region of the Hexi Corridor

作　　者：赵一丹 陈拓 刘阳 张璐 张怡洋 张威 章高森 Zhao Yidan;Chen Tuo;Liu Yang;Zhang Lu;Zhang Yiyang;Zhang Wei;Zhang Gaosen(State Key Laboratory of Cryospheric Sciences/Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;Gansu Province Key Laboratory of Extreme Environmental Microbial Resources and Engineering/Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;Key Laboratory of Desert and Desertification,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院西北生态环境资源研究院,冰冻圈科学国家重点实验室,甘肃兰州730000 [2]中国科学院西北生态环境资源研究院,甘肃省极端环境微生物资源与工程重点实验室,甘肃兰州730000 [3]中国科学院西北生态环境资源研究院,沙漠与沙漠化重点实验室,甘肃兰州730000 [4]中国科学院大学,北京100049

出　　处：《中国沙漠》2024年第5期23-28,共6页Journal of Desert Research

基　　金：中国载人空间计划空间应用系统项目(KJZ-YY-WSM05);中国科学院“西部之光”计划项目(xbzg-zdsys-202105);国家自然科学基金项目(31870479)。

摘　　要：以往对石下生微生物的研究集中在微生物组成和分布特征上,而对光合活性变化的研究较少。以分布在河西走廊3个干旱程度不同样地的石下生蓝藻为材料,利用Handy PEA植物效率仪,研究了在72 h内石下生蓝藻的叶绿素荧光参数的逐小时日变化特征。结果表明:(1)石下生蓝藻PSII最大光化学量子产量(F_(v)/F_(m))的值均存在明显的日变化,在06:00左右及18:00—20:00达到较高水平,最高值均大于0.6;由于受到环境胁迫,在辐照度较高(>2 m W·cm^(-2))、温度较高(>30℃)、湿度较低(<12.5%)的12:00—14:00,F_(v)/F_(m)的值均低于0.1;(2)降雨事件的发生使得瓜州北戈壁石生蓝藻F_(v)/F_(m)的值明显增高,平均值0.1~0.35,嘉峪关大草滩F_(v)/F_(m)的值波动较小,平均值0.1~0.19,这可能与该地区石头类型、土壤类型和降雨量大小有关。该研究在一定程度上揭示了石下生蓝藻光合活性在一天内的变化情况,为深入研究石下生微生物在原位环境的代谢活动提供线索。Fewer studies have been conducted on changes in the photosynthetic activities of hypolithic microorganisms,with the majority of previous research concentrating on the microbial composition and distributional properties.The hour-by-hour daily variation characteristics of chlorophyll fluorescence parameters of three hypolithic cyanobacteria distributed in three different aridity levels of the Hexi Corridor were studied as experimental materials using the handy PEA plant efficiency meter over a 72-hour period.The results showed that the hypolithic cyanobacteria exhibited daily fluctuations in their maximum photochemical quantum yield(F_(v)/F_(m))values,reaching a higher level at approximately 06:00 a.m.and 18:00-20:00 p.m.,with the greatest values above 0.6.The F_(v)/F_(m)values were less than 0.1 at 12:00-14:00 at higher irradiance(>2 m W·cm^(-2)),higher temperature(>30℃),and lower humidity(<12.5%)as a result of the environmental stress.Rainfall events,which may be related to the type of stone,soil,and rainfall amount in this area,caused significantly higher values of F_(v)/F_(m)for hypolithic cyanobacteria in the North Gobi of Guazhou(GZ),with mean values fluctuating from 0.1 to 0.35,and smaller fluctuations of F_(v)/F_(m)in the Dacaotan of Jiayuguan(JYG),with mean values ranging from 0.1 to0.19.This work exposes,to some extent,variations in photosynthetic activity of hypolithic cyanobacteria throughout a day and offers a theoretical foundation for the study of hypolithic microbial communities.

关 键 词：河西走廊 石下生微生物 叶绿素荧光 蓝藻光合活性 日变化 

分 类 号：Q935[生物学—微生物学]