Leaf physiological traits of plants from the Qinghai-Tibet Plateau and other arid sites in China: Identifying susceptible species and well-adapted extremophiles

• Published in: Journal of plant physiology Vol. 272; p. 153689
• Main Authors: Flexas, Jaume, Zhang, Yali, Gulías, Javier, Xiong, Dongliang, Carriquí, Marc, Baraza, Elena, Du, Tingting, Lei, Zhangying, Meng, Haofeng, Dou, Haitao, Ribas-Carbo, Miquel, Xiang, Dao, Xu, Wenbin
• Format: Journal Article
• Language: English
• Published: Germany Elsevier GmbH 01.05.2022; Elsevier Science Ltd
• Subjects: Arid lands; Arid zones; Aridity; Biodiversity; C4 species; Chlorophyll; Conservation physiology; Drought resistance; Extreme environments; Fluorescence; Gas exchange; In situ measurement; Indigenous plants; Leaf traits; Leaves; Photosynthesis; Physiology; Plant physiology; Plants; Plants (botany); Setaria viridis; Stress physiology; Threatened species; Water use; Water use efficiency; Wildlife conservation; Tibetan Plateau; China; Conservation physiology; C4 species; Photosynthesis; Leaf traits; Stress physiology; C species
• ISSN: 0176-1617; 1618-1328
• DOI: 10.1016/j.jplph.2022.153689

Extreme environments, such as deserts and high-elevation ecosystems, are very important from biodiversity and ecological perspectives. However, plant physiology at those sites has been scarcely studied, likely due to logistic difficulties. In the present study, leaf physiological traits in native plants were analyzed from arid zones across an elevational transect in Western China, from Turpan Basin to the Qinghai-Tibet Plateau (QTP) at Delingha. The aim of this study was to use leaf physiological traits to help identifying potentially threatened species and true extremophiles. Physiological measurements in the field, and particularly in situ measurements of gas exchange and chlorophyll fluorescence, have been determined to be useful to determine the current state of plants at a given environment. Using this approach plus a combination of leaf traits, several species performing particularly well at the QTP were identified, e.g. Hedysarum multijugum, as well as at Manas drylands, e.g. Peganum harmala and Setaria viridis. On the other hand, several species showed marked signs of severe stress, in particular a very low photosynthetic rate over its potential maximum, as well as other negative traits, like low water and/or nitrogen-use-efficiency, which should be considered in conservation plans. Interestingly, all C4 species studied except Setaria viridis were among the most stressed species. Despite their higher water use efficiency and drought-tolerance reputation, they presented a much larger photosynthesis depression than most C3 species. This is an intriguing and interesting observation that deserves further studies. •Physiological traits were measured in the field from the Turpan Basin to the QTP.•Potential extremophile species were identified, as well as severely stressed species performing.•C4 species were more affected by the prevalent stress conditions than most C3 species.