The Response Of The Growth Of Larix Gmelinii To The Climate Change In Great Khingan

This paper takes Larix gmelinii Rupr. ex Kuzen. as the research object, builds the chronology tree-ring width at different latitudes,analyzes the changes of tree growth and climate factor, use correlation analysis method studies the relationship between radial growth at different latitudes and climate factors, and reveals the influences of climatic change to the growth of Larix gmelinii Rupr. ex Kuzen. in Great Khingan. The primary results are:(1)In recent decades, the average temperature, maximum temperature and minimum temperature showed a significant increasing trend at different latitudes in Great Khingan, the increasing of temperature of average temperature,maximum temperature and minimum temperature in northern area is0.44℃/10a,0.49℃/10a,0.36℃/10a,the increasing of temperature in central area is0.52℃/10a,0.39℃/10a,0,72℃/10a, the increasing of temperature is0.49℃/10a,0.39℃/10a,0.70C/10a. Before1985,the temperature in northern has little change, the central and southern area rise,between1985-1990, the temperature of each latitude showed significant upward trend. The temperature of northern area decrease, the central area rise, the southern area has little change after1990,(2)Each month of each layer soil temperature show a warming trend in difernent latitudes except the temperature of5cm in June in central area, the average temperature of of each layer of5-9months increase, the variation of the same area of each layer soil temperature is consistent. Precipitation in the northern and southern area show a downward trend,the central area increase, but not reach the significant level. The precipitation of northern and southern area has little change before1990,the central area increase, the precipitation of northern,central and southern area show a downward trend since1990.(3)The standard chronology of northern area of Great Khingan shows the increasing trend of trees growtn in the period1927-2008, this trend can be divided into three stages:It has a little change before the twentieth century70’s, a significant increase trend from the beginning the70’s to the end of80’s, a decline trend after90’s, corresponding to this, the growth of central and southern area do not change significant over the entire time,do not appear the phenomenon that as temperature rise tree growth rise, display the different response to climate warming in different latitudes, due to the relatively good conditions in central and southern area,the rise of temperature has little effect on the growth of trees.(4)In the northern area, it illustrate that the radial growth of Larix gmelinii Rupr. ex Kuzen. is mainly influenced by rising temperature conditions in th early70’s to the late80’s, no matter the result of correlation analysis or the change with time. In this period, precipitation conditions has little effect on the growth of Larix gmelinii Rupr. ex Kuzen. the radial growth decline of Larix gmelinii Rupr. ex Kuzen reflect the change of precipitation after90’s.