Comparison of the response stability of Siberian larch to climate change in the Altai and Tianshan

Abstract

There is a spatial, geographical pattern of different tree growth responses to climate change, and global warming also leads to temporal nonlinear responses of tree radial growth to climatic factors. Therefore, we evaluated response stabilities to climate change and compared the growth trends of Siberian larch in the Altai and Tianshan Mountains of Northwest China. The main conclusion was as follows: 1) temperature was the dominant limiting climatic factor for Siberian larch in the two study regions. The radial growth in the Altai Mountains was mainly controlled by the minimum and maximum temperatures in July of the previous year, in May, June, and July of the current year from 1958 to 1985, and in January, February, and April of the current year from 1986 to 2012. In addition, the radial growth in the Tianshan Mountains was mainly controlled by the minimum temperature in July of the current year from 1958 to 1985, and in June of the previous year from 1986 to 2012. 2) Siberian larch in the Altai and Tianshan Mountains all had divergent responses to climate change. The relationships between radial growth of the Siberian larch in the Altai Mountains and the minimum temperature in July, September of the previous year and February, March, May, July of the current year showed an unstable correlation. The relationships between radial growth of the Siberian larch in the Tianshan Mountains and the minimum temperature in November of the previous year and May, July, September of the current year showed unstable correlation. 3) The trend in the interannual change of the basal area increment (BAI) of Siberian larch in the Altai Mountains was not significant (p > 0.05), but there was first an increasing and then a decreasing trend in the Tianshan Mountains (p < 0.05) with climate change. Siberian larch trees in the Tianshan Mountains were more susceptible to drought stress than those in the Altai Mountains.