Abstract: The heterogeneity of response of treering width of Abies fargesii to climate change in the Niubeiliang Nature Reserve of the Qinling Mountains was analyzed by dendroclimatological methods during periods of 1969-1992 and 1993-2013. The results showed that a divergence problem existed in the radial growth responses of A. fargesii to temperature indicators in the study area. The characterization of A. fargesii radial growth chronology series was explored by correlation analysis and response function analysis. During 1969-1992, the treering widths of A. fargesii did not correlate with the mean annual and seasonal temperature, but had significant negative correlations with the mean temperature of March and September and the precipitation of February and April in the current year. In addition, the treering width of A. fargesii showed a significant positive correlation with the mean temperature of May in the current year. During the period of 1993-2013, the treering widths of A. fargesii showed a significant positive correlation with the mean temperature of the previous autumn, especially in the previous October, while a negative correlation with the precipitation in February of the current year. Moreover, the treering width of A. fargesii was negatively correlated with the average rainfall in the previous winter during the two periods. This study indicated that in the context of global warming, the responses of A. fargesii radial growth to climatic variables were different in the two periods in the Niubeiliang Nature Reserve of the Qinling Mountains.

Key words: hydroponics, accumulation and utilization., potassium, tea seedling