The Study On The Climatic Response Of The Growth Of Pinus Koraiensis In The Of XiaoXing'AnLing Based On The TREE-RING Eco-physiological Model

Tree monitor environmental conditions that limit their biological processes and this information are stored in the structure of the annual ring.Tree-ring width data may reflect a nonlinear response to multivariate climate forcing.Single-variable paleoclimatic reconstruction via linear statistical calibration maybe represents a problem.Because there are nonclimatic influence on tree-ring records,including tree bilogy,size and age et al.Statistical relationships which may represent linearization of nonlinear processes are difficult to validate for long period processes for times outside the instrumental era.Moreover,traditional statistical techniques are inadequate when describing tree-growth responses to climate on cellular level.In this paper,we use the TREE-RING model to simulate climatic response of Pinus koraiensis in the lower mountains of XiaoXing'AnLing and discuss its hysiological response mechanism.Tree ring data were collected from Pinus koraiensis in the lower mountains of XiaoXing'AnLing.The climate data used in this study include local daily maximum temperature,minimum temperature and precipitation records from National Meteorological Information Center,China Meteorological Administration. Through model parameter debug and simulation result analysis,we can draw some main conclusions as follow:(1) A comparison between simulated and measured tree-ring series shows that the TREE-RING model could simulate the Pinus koraiensis tree-growth well.the correlation of cell number between the measured and modeled series equal to 0.62,and the value has exceed 99%degree of confidence.Pinus koraiensis grow starts average on April 25,cease on October 9,and the average growing time is 167 days.(2) The simulation results indicated that variations in tree-ring width are mainly controlled by October temperatures of the last year to growth and April temperatures of the growth year.Cambium growth begins in the last ten-day of April when there is enough water,but temperatures are low in XiaoXing'AnLing,and cambium growth ends in the first ten-day of October,but temperatures of October are between Lower optimal and minimum temperature for photosynthesis,where the photosynthetic rate increases at higher temperature.Thus,more food is stored at higher October temperature,and wider ring was easy to form the next year to grow. (3) Sensitivity analysis of parameter indicated that the tree-ring growth was sensitive to minimum temperature for photosynthesis,lower optimal temperature for photosynthesis,upper optimal volumetric water content and maximum volumetric water content.Sensitivity analysis of climate show tree growing start will bring forward and the increment will reduce if dailly temperature increases 1℃from 1958 to 1998.Sensitivity analysis of atmosphere CO₂ display the model is sensital to CO₂ variation.The result validate CO₂ contration increasing will accelerate tree grow.(4) Based on simulation record,the mean temperature of October was reconstructed for the period of 1796 to 2004 using RES tree ring chronology.The explained variance of reconstruction is 34.8%.In the past 209 year,there were 4 colder periods and 4 warmer periods in reconstructed series.(5) Through comparing with research result of different area in China,we found cold period concurrence in Wu ying,Changbai,East of China and Urumqi river source of Tianshan Mountain from 18 century end to 19 century 40's.Warm period alse concurrence in there area from 19 century 70's to 19 century end.(6) Periods of 3a,6a,20a and 40a were found markedly in the reconstruct series by power spectrum and wavelate analysis.The abrupt changes were also be detected with 30-year time scale and 15-year time scale by the smoothing T test,the smoothing F test and Lepage test methods.The significant abrupt changes of 30-year time scale mean value were present in around A.D.1871 and 1900 and the significant abrupt changes of standard deviation in around A.D.1851.The significant abrupt changes of 15-year time scale mean value were present in around A.D.1822,1847,1871,1900 and 1987,and the significant abrupt changes of standard deviation in around A.D.1851,1973 and 1988.