Response of Radial Growth of Pinus massoniana to Climate Change in Central Guizhou Province

Taking Pinus massoniana in central Guizhou as the object of study, a standard chronology of P. massoniana was established with tree-ring, and correlation analysis between radial growth and local climatic factors such as temperature and rain precipitation have been conducted. The results showed that the radial growth of P. massoniana in central Guizhou Province is sensitive to temperature and the series of tree-ring widths exhibited significantly positive correlations with the local temperature in February and from February to April of the consecutive months. Also, extreme minimum temperature in February can limit the growth of P. massoniana of current, indicating the temperature in the early growing season in central Guizhou promotes the radial growth of P. massoniana.The correlation between precipitation and tree-ring was not significant, but the tree-ring width of P. massoniana yielded significantly positive correlations with the local air relative humidity in March and June of the current, indicating that air relative humidity was also an important environmental factor effecting the growth of P. massoniana during the early and middle part of the season. In the continuous month scale, the air relative humidity from October of last year to February of the current year showed a significant positive correlation, indicating that the radial growth of P. massoniana is greatly affected by the air relative humidity of the previous year and the response of radial growth to air relative humidity had lag effect. To sum up, temperature and air relative humidity in the early and middle growing season are the main climatic factors effecting the radial growth of P. massoniana in central Guizhou, especially the temperature in February may play a key role.