Full-Text Search:
Home|Journal Papers|About CNKI|User Service|FAQ|Contact Us|中文
《Journal of Arid Land Resources and Environment》 2017-09
Add to Favorite Get Latest Update

Diurnal and seasonal variations in net ecosystem CO_2 exchange of a desert riparian Populus Euphratica forest

MA Xiaohong;FENG Qi;SU Yonghong;YU Tengfei;JING Hua;Northwest Institute of Eco-Environment and Resources,CAS;Key Laboratory of Eco-hydrology of Inland river Basin,CAS;University of Chinese Academy of Sciences;  
The sound and steady progress of the Populus Euphratica forest is not only conductive to prevent the further desertification,but also can help to maintain ecological security of Ejina oasis. So far,the process and change characteristics of the net ecosystem CO_2 exchange are still unknown and the amount of carbon assimilation and release need to be quantified. Thus,the characteristics of net ecosystem CO_2 exchange in the P. euphratica forest was analyzed in this study. And the data was derived from two eddy covariance flux observation sites in the P. euphratica forest in 2014. Accordingly,some conclusions were given as follows.( 1) In the growing season,from May to October the monthly F_(NEE)were 24. 45,-46. 10,-60. 48,-50. 70,-34. 30 and 17. 18g·C·m~(-2)·mon~(-1),respectively. The total value of F_(NEE)was -198. 85g·C·m~(-2)in the whole growing season.( 2)The diurnal course of F_(NEE) was obviously different at monthly level. The amount of carbon assimilation in daytime and carbon release in night varied as the P. euphratica growing. The highest uptake in the midday( 10: 00-15: 00) and release in night of CO_2 were occurred in July.( 3) The diurnal course of F_S was similar in different months,whereas the contribution of F_S to F_(NEE)was significant. However,the ratio of F_S to F_(NEE)was less than 3. 2% in month and the contribution of F_S to F_(NEE)could be neglected under monthly or seasonal scale.( 4) Photosynthetic Active Radiation( PAR) and Leaf Area Index( LAI) were the main drivers in variation of net ecosystem exchange at daily or monthly scale.
【Fund】: 国家自然科学基金重大研究计划(91125002);; 国家自然基金项目(31370466);国家自然基金面上项目(31370467);; 国家自然科学青年基金项目(41401033)资助
【CateGory Index】: S718.55
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©2006 Tsinghua Tongfang Knowledge Network Technology Co., Ltd.(Beijing)(TTKN) All rights reserved