Tree-Ring Carbon Isotopic Constraints on Carbon-Water Exchanges between Atmosphere and Biosphere in Drought Regions in Northwestern China

作     者：WANG Shilu WAN Guojiang 

作者机构：State Key Laboratory of Environmental GeochemistryInstitute of GeochemistryCASGuiyang 550002 

出 版 物：《Acta Geologica Sinica(English Edition)》 (地质学报（英文版）)

年 卷 期：2000年第74卷第2期

页      面：301-305页

核心收录：

学科分类：07[理学] 070601[理学-气象学] 0706[理学-大气科学] 

基　　金：The work was supported by the National NaturalScience Foundation of China (Grant Nos.49333040 and 49903007) 

主　　题：tree ring carbon isotope CO_(2) exchange water-use efficiency 

摘      要：The comparison between the carbon isotope and the index of ring width of a pine disc from the Tuomuer Peak region in Xinjiang shows that the effects of climate changes on the tree-ring growth and carbon isotopic fractionation varies with time. The reason is probably relative to the characters of climate changes and adaptability of the tree-ring growth to climate changes. The relationships between the atmospheric CO2 level and the revised δ13Cair by the tree-ring carbon isotope indicate that the carbon cycle is not in a steady state, but under a stage-change condition in this area. It also can be concluded that the ratio of CO2 from the terrestrial eco-system has increased, and the flux of CO2 exchange between the atmosphere and the biosphere was gradually increasing over the past century. In addition, the results also confirm the validity and superiority of the carbon isotope to the research of the water-use efficiency.