Photosynthesis of Populus euphratica and its response to elevated CO2 concentration in an arid environment

• Published in: Progress in natural science Vol. 19; no. 4; pp. 443 - 451
• Main Authors: Zhou, Honghua, Chen, Yaning, Li, Weihong, Chen, Yapeng, Fu, Lixin
• Format: Journal Article
• Language: English
• Published: Graduate School of Chinese Academy of Sciences,Beijing 100039,China%Key Laboratory of Oasis Ecology and Desert Environment,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China 10.04.2009; Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,818 South Beijing Road,Urumqi,Xinjiang 830011,China; Key Laboratory of Oasis Ecology and Desert Environment,Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China; Graduate School of Chinese Academy of Sciences,Beijing 100039,China%College of Natural Resources and Environment Science of Xinjiang Agricultural University,Urumqi 830052,China
• Subjects: CO2 concentration; Groundwater depth; Populus euphratica; Photosynthesis; The lower reaches of the Tarim River
• ISSN: 1002-0071
• DOI: 10.1016/j.pnsc.2008.10.002

O4; The photosynthetic characterization of Populus euphratica and its response to the elevated carbon dioxide concentration ([CO2]) were analyzed based on its net photosynthetic rate (Pn),stomatal conductance (gs),intercellular CO2 concentration (Ci),transpiration rate (Tr),and water use efficiency (WUE) at different groundwater depths measured by a portable gas exchange system (LI-6400) in the lower reaches of the Tarim River.The results showed that the elevation of [CO2]decreased the gs,and increased the Pn,Ci and WUE of P.euphratica.However,the effects of the elevated [CO2]on gs,Pn,Ci and WUE varied considerably with groundwater depth.The response of photosynthesis to rising [CO2]was stronger at the greater groundwater depth (more than 6 m) than that at the shallower groundwater depth (less than 6 m).The critical groundwater depth required to maintain the normal survival of P.euphratica was less than 6 m.When the groundwater depth increased to more than 6 m,P.euphratica encountered moderate water stress,and the plant suffered severe water stress when the groundwater depth increased to more than 7 m.