Effect Of Different Site Conditions On The Growth Of Tree-Ring Width Of Pinus Sylvestris Var.Mongolica And Its Response To Climate Change

In this paper, pinus sylvestris in Daxinganling region is the research object, and samples are took in two research regions, Mordaga and Honghuaerji, to analyze growth characteristic of diameter of pinus sylvestris in different site conditions, and to describe growth characteristics of montane pinus sylvestris and sandy pinus sylvestris by Logistic model By applying two research regions’ samples, tree--ring width chronology is established. In addition, this paper analyzes the correlation between chronology of montane pinus sylvestris and sandy pinus sylvestris, and climatic factors, and reveals response from growth of diameter of pinus sylvestris to main climatic factors in different site conditions. The main research conclusions are as follows:(1)The tree--ring width chronology of montane pinus sylvestris in Mordaga has higher total representativeness of sample, mean sensitivity, and signal noise, when the tree--ring width chronology of sandy pinus sylvestris in Honghuaerji also has high mean sensitivity and total representativeness of sample. The chronology established by samples of two research zones both contain many climate information, and are appropriate to be applied to analyze the correlation between growth of tree diameter and climate factors.(2)Both chronologies of montane pinus sylvestris and sandy pinus sylvestris are significantly correlated with amount of precipitation in October last year, and have a significant negative correlation with mean monthly temperature in the summer at current year. Montane pinus sylvestris has significant negative correlation with winter’s precipitation, when sandy pinus sylvestris has significant positive correlation with precipitation from May to August. Both chronologies show low correlation with maximum and minimum temperatures.(3) In this paper, Mordaga research region is divided into three site conditions, which are, middle slope, top slope, and lower slope, when Honghuaerji is divided into two types, which are, dune slack and fiat sand land. Through research on growth rules of pinus sylvestris of different ages in different site conditions, here comes a result, which is, at 96 year of age, the pinus sylvestris with the biggest diameter growth is the pinus sylvestris at dune slack in Honghuaerji, followed by pinus sylvestris at the top slope on Mordaga, and then pinus sylvestris at flat sand land, at middle slope, and at lower slope.