Responses Of Tree Growth Of Fokienia Hodginsii To Climate Change In Changting,Fujian Province

According to the standard methods and principles of dendrochronology,the samples of Fokienia hodginsii were collected from the Guilong Mountain Nature Reserve in Changting,Fujian Province,Two core samples were taken from the growth cone at different positions,The sample core back to the laboratory for pretreatment,Including fixed,dry,polished,The tree-ring width was measured by Lintab-6 tree-ring analyzer,Using COFECHA software to test the tree wheel sequence and the final dating,ARSTAN software to remove the growth trend of trees,two chronologies were obtained for standardization and difference.We make the correlation analysis and response analysis between the chronology and the relative humidity,the monthly precipitation,the monthly minimum temperature,the monthly maximum temperature and the monthly average temperature index.we developed the first tree-ring chronology of Fokienia hodginsii over the humid subtropics and investigated the climate-growth relationships.Tree growth is positively correlated with current autumn(from September to October)temperature and previou s spring-summer(from April to August)precipitation.Results of moving correlation a nalysis with a 25-yr window reveal that despite of the instability of the relationships b etween tree growth and temperature and precipitation,the relationships are both evide nt during the period from 1970s to 1990s.This finding suggests that climate variabilit y may be more limited to tree growth during this epoch.In addition,we also find that t he radial growth of Fokienia hodginsii cannot be promoted highly simply because of t he increase of temperature or precipitation.The notable promotion of growth occurs w hen both temperature and precipitation rise.Under the background of global warming in the future,if the increase in precipitation is absent,the carbon sequestration of Foki enia hodginsii woods may not be significantly enhanced.