Responses Of Tree-ring Width Of Pinus Massiniana To Climate Change In Sanming, Fujian Province

Using the basic principle and method of Dendrochronology, according to tree-ring samples of Pinus massiniana, in Catanopsis kawakamii Forest Ecosystem Research Station in Sanming city, Fujian Province, we get the cores through drilling four holes into the tree of diameter at different direction by the growth cone, after retrieving the laboratory, taking a serious treatment:fastening, drying and polishing. Preliminary dating the years by eyes, and begun the measurement of tree-ring width by the Lintab-6. Using its software TSAP (time series analysis presentations), we can obtain the tree ring width sequences, and then throuth COFECHA software check the validity of the series and wipe off little sensitive series or the mistake series. Using a negative exponential curve to get off the growing trend of trees The chronology of Pinus massiniana in natural forest and plantation were developed by the program ARSTAN. Explore the response of Pinus massiniana radial growth and climatic factors.In the end, we have established a standard tree-ring chronology. To explore the climate significance of tree ring width of Pinus massiniana in the study of dendroclimate, correlation analyses were conducted between the chronology and five climate variables. These climate variables include monthly mean temperature, monthly precipitation, monthly mean relative humidity, monthly sunshine hours and PDSI, all of which cover the period from 1951 to 2011. The results of correlation analysis showed that the radial growth of Pinus massiniana was significantly correlated with the July-August temperature in the previous year and the July-August mean temperature of the current year (p<0.01). The radial growth showed significant correlations with the precipitation from last year January-March (p<0.01) and current year June-November (P<0.01). The chronology had significant correlations with the relative humidity in the previous February-March (p<0.01) and the current July-August (p<0.01). Besides, significant positive correlations were observed between the tree ring width and the sunshine hours of the previous February-March (p<0.01). In addition, the growth of Pinus massoniana significant positive correlations with PDSI from June to November, suggesting a drought stressed growth pattern. Our study indicate that tree growth in this region is influenced by various factors and the climate-growth relationships vary through time.