Effects of drought and heat on the productivity and photosynthetic characteristics of alpine meadow plants on the Qinghai-Tibetan Plateau

作     者：MA Li ZHANG Zhong-hua YAO Bu-qing MA Zhen HUANG Xiao-tao ZHOU Bing-rong XU Man-hou GUO Jing ZHOU Hua-kun MA Li;ZHANG Zhong-hua;YAO Bu-qing;MA Zhen;HUANG Xiao-tao;ZHOU Bing-rong;XU Man-hou;GUO Jing;ZHOU Hua-kun

作者机构：Key Laboratory of Restoration Ecology of Cold Area in Qinghai ProvinceNorthwest Institute of Plateau BiologyChinese Academy of SciencesXining810008China The Qinghai Institute of Meteorological ScienceXining810001China Taiyuan Normal UniversityJinzhong030619China University of Chinese Academy of SciencesBeijing100049China Qinghai Academy of Social SciencesXining810000China 

出 版 物：《Journal of Mountain Science》 (山地科学学报（英文）)

年 卷 期：2021年第18卷第8期

页      面：2079-2093页

核心收录：

学科分类：09[农学] 0903[农学-农业资源与环境] 

基　　金：supported by the National Natural Science Foundation of China (31672475) Natural Science Foundation of Qinghai Province (2019-ZJ908) National Key Research and Development Program of China (2016YFC0501901) the Second Comprehensive Scientific Investigation of the Tibetan Plateau (2019QZKK0302) 

主　　题：Alpine meadow Drought stress Heat stress Productivity Photosynthetic characteristics 

摘      要：Alpine meadow plants,adapted to humid and cold environments,are highly sensitive to environmental factors such as drought and ***,the physiological responses of individual alpine meadow species to drought and heat stress remain *** this study,four representative species of typical functional groups in an alpine meadow of the Qinghai-Tibet Plateau were selected as experimental ***(H1,H2),drought(D1,D2),and combined stress(D1H1,D2H2)treatments were implemented to reveal the biomass and physiological characteristics’response to a constant drought and heat *** results showed that the leaf water content(LWC)of Kobresia humilis and Poa annua increased significantly under heat stress and the compound stress(P0.05).The effect of a single factor on LWC was greater than that of multiple *** aboveground biomass(AGB)of Oxytropis ochrocephala and Saussurea pulchra decreased significantly under compound stress(P0.05).The response patterns of the net photosynthetic rate(Pn)and transpiration rate(Tr)of *** and *** under various stress treatments were similar;as were those of *** and *** stomatal conductance(Gs)variation in ***,***,***,and *** were the same under three kinds of stress *** photosynthetic characteristics were more sensitive to the effects of composite than those of single *** drought×heat×species treatment had a significant influence on various indexes except on height(Ht)and the belowground biomass(BGB)(P0.01).Within a certain range,daytime temperature(DT)promoted the Ht and increased the LWC of the plants,while it inhibited their AGB and intercellular CO2 concentration(Ci).The Pn,Tr,and Gs were more sensitive to soil moisture than to *** results help improve understanding of the physiological response regularity of representative alpine meadow plant species to continuous drought and high temperature conditions at the species level,and pro