In order to investigate the response to climate changes in radial growth of Picea crassifolia at the lower tree line in the middle Qilian mountains in northwestern China, relationships of standardized chronologies of ...In order to investigate the response to climate changes in radial growth of Picea crassifolia at the lower tree line in the middle Qilian mountains in northwestern China, relationships of standardized chronologies of annual ring, earlywood and latewood widths with mean monthly temperature and total monthly precipitation were analyzed by ways of correlation and pointer year analyses. The results show that annual ring, earlywood and latewood widths are significantly negatively correlated with mean monthly temperature in June and July. Annual ring and earlywood widths are significantly and positively correlated with total monthly precipitation in March, May and June and negatively correlated with total monthly precipitation in September. Latewood width is less sensitive to climate changes than the width of earlywood and insignificantly sensitive to precipitation. The results of pointer year analysis revealed that when summer temperatures are higher than the mean summer temperature synchronization and the summer precipitation lower than mean summer precipitation synchronization, narrow annual rings are formed. Wide annual rings are formed when summer temperatures are lower than the mean summer temperature synchronization and summer precipitation higher than mean summer precipitation synchronization. The results indicate that more precipitation in the spring and summer is helpful for radial growth while warmer summer restricts radial growth of P. crassifolia at the lower tree line in the middle Qilian mountains.展开更多
Based on plant phenology data from 26 stations of the Chinese Phenology Observation Network of the Chinese Academy of Sciences and the climate data, the change of plant phenophase in spring and the impact of climate w...Based on plant phenology data from 26 stations of the Chinese Phenology Observation Network of the Chinese Academy of Sciences and the climate data, the change of plant phenophase in spring and the impact of climate warming on the plant phenophase in China for the last 40 years are analyzed. Furthermore, the geographical distribution models of phenophase in every decade are reconstructed, and the impact of climate warming on geographical distribution model of phenophase is studied as well. The results show that (i) the response of phenophase advance or delay to temperature change is nonlinear. Since the 1980s, at the same amplitude of temperature change, phenophase delay amplitude caused by temperature decrease is greater than phenophase advance amplitude caused by temperature increase; the rate of phenophase advance days decreases with temperature increase amplitude, and the rate of phenophase delay days increases with temperature decrease amplitude. (ii) The geographical distribution model between展开更多
基金financially supported by the Special Fund of the National Public Welfare Industry (Forestry) (No.200804001)the National Science Fund for Distinguished Young Scholars (No.30825034)
文摘In order to investigate the response to climate changes in radial growth of Picea crassifolia at the lower tree line in the middle Qilian mountains in northwestern China, relationships of standardized chronologies of annual ring, earlywood and latewood widths with mean monthly temperature and total monthly precipitation were analyzed by ways of correlation and pointer year analyses. The results show that annual ring, earlywood and latewood widths are significantly negatively correlated with mean monthly temperature in June and July. Annual ring and earlywood widths are significantly and positively correlated with total monthly precipitation in March, May and June and negatively correlated with total monthly precipitation in September. Latewood width is less sensitive to climate changes than the width of earlywood and insignificantly sensitive to precipitation. The results of pointer year analysis revealed that when summer temperatures are higher than the mean summer temperature synchronization and the summer precipitation lower than mean summer precipitation synchronization, narrow annual rings are formed. Wide annual rings are formed when summer temperatures are lower than the mean summer temperature synchronization and summer precipitation higher than mean summer precipitation synchronization. The results indicate that more precipitation in the spring and summer is helpful for radial growth while warmer summer restricts radial growth of P. crassifolia at the lower tree line in the middle Qilian mountains.
基金This work was supported by the Chinese Academy of Sciences (Grant No. KZCX2-314), the National Natural Science Foundation of China (Grant No. 49901001), and Institute of Geographic Sciences and Natural Resources Research, the Chinese Academy of Sciences
文摘Based on plant phenology data from 26 stations of the Chinese Phenology Observation Network of the Chinese Academy of Sciences and the climate data, the change of plant phenophase in spring and the impact of climate warming on the plant phenophase in China for the last 40 years are analyzed. Furthermore, the geographical distribution models of phenophase in every decade are reconstructed, and the impact of climate warming on geographical distribution model of phenophase is studied as well. The results show that (i) the response of phenophase advance or delay to temperature change is nonlinear. Since the 1980s, at the same amplitude of temperature change, phenophase delay amplitude caused by temperature decrease is greater than phenophase advance amplitude caused by temperature increase; the rate of phenophase advance days decreases with temperature increase amplitude, and the rate of phenophase delay days increases with temperature decrease amplitude. (ii) The geographical distribution model between
