Spatiotemporal variability in tree ring's δ^(13)C of Picea crassifolia in the Qilian Mountains:climatic significance and responses to rising CO_2  

作　　者：XiaoHong Liu WenLing An ErYuan Liang WenZhi Wang XueMei Shao Lei Huang DaHe Qin 

机构地区：[1]State Key Laboratory of Cryospheric Sciences, CoM and Arid Regions Environmental and Engineering Research Institute, Lanzhou, Gansu 730000, China [2]Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China [3]Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China [4]National Climate Centre, China Meteorological Administration, Beijing 100081, China

出　　处：《Research in Cold and Arid Regions》2011年第2期93-102,共10页寒旱区科学（英文版）

基　　金：supported by the Natural Science foundation in China (Grant No. 40871002,40501076);the Knowledge Innovation Project of the Chinese Academy Sciences (KZCX2-YW-QN308);the Self-determination Project of State Key Laboratory of Cryospheric Sciences (SKLCS09-03)

摘　　要：Abstract：The carbon isotopic composition （δ13C） of tree rings was used to assess changes in intrinsic water-use efficiency （Wi） to increasing atmospheric CO2 and climate change during the period of 1891–2003. Five Qinghai spruce （Picea crassifolia） stands were selected in the Qilian Mountains, growing along a precipitation gradient. All five δ13C were correlated to each other, but two sites （DDS and CLS）, which are far from the main body of the mountains, show relative weak connections to other sites. Although trees at all sites had improved their Wi in response to increasing atmospheric CO2 concentration, spruce growing in the regions far away from the main body of the mountains were less sensitive to improved Wi than those of other sites. Based on the correlation between carbon isotope discrimination （Δ） and Palmer Drought Severity Index （PDSI）, the drought history covering the period of 1891–2003 was reconstructed in the study region. The two most severe drought epochs of the late 1920s and the last decade were caused by reduced precipitation and climate warming, respectively. Our results will be useful in assessing any further spatial climate-related bioclimatic information.Abstract：The carbon isotopic composition （δ13C） of tree rings was used to assess changes in intrinsic water-use efficiency （Wi） to increasing atmospheric CO2 and climate change during the period of 1891–2003. Five Qinghai spruce （Picea crassifolia） stands were selected in the Qilian Mountains, growing along a precipitation gradient. All five δ13C were correlated to each other, but two sites （DDS and CLS）, which are far from the main body of the mountains, show relative weak connections to other sites. Although trees at all sites had improved their Wi in response to increasing atmospheric CO2 concentration, spruce growing in the regions far away from the main body of the mountains were less sensitive to improved Wi than those of other sites. Based on the correlation between carbon isotope discrimination （Δ） and Palmer Drought Severity Index （PDSI）, the drought history covering the period of 1891–2003 was reconstructed in the study region. The two most severe drought epochs of the late 1920s and the last decade were caused by reduced precipitation and climate warming, respectively. Our results will be useful in assessing any further spatial climate-related bioclimatic information.

关 键 词：Tree-ring δ13C intrinsic water-use efficiency drought history Picea crassifolia Qilian Motmtains 

分 类 号：P467[天文地球—大气科学及气象学] X16[环境科学与工程—环境科学]