不同去趋势方法对格尔木地区胡杨宽度年表的气候意义影响分析

基于2014年采自柴达木盆地南缘格尔木地区的胡杨树轮样本,采用三种不同去趋势方法(样条函数法、负指数拟合和区域曲线去趋势方法)建立树轮标准化序列,结合格尔木气象站气候资料,分析不同去趋势方法下胡杨径向生长对气候的响应。研究表明,利用区域去趋势方法建立的树轮年表包含有较多的气候环境信息,胡杨树轮年表与逐月气候因子相关表明,树轮年表对降水响应不显著,与生长季的平均气温和平均最高气温有较好的相关性,最高相关系数达0.411(p0.01),格尔木胡杨树轮的区域去趋势年表与组合相关的6—10月平均最高气温相关性最好,生长季的平均最高气温对胡杨径向生长有一定的限制作用并具有树木生理学意义。用区域曲线去趋势方法得出的格尔木胡杨树轮年表对气候的响应最好。

Development of Populus euphratica tree-ring chronology and its response to climate on southern margin of Qaidam Basin, based on different detrending method

In this paper, Populus euphratica tree ring samples on southern margin of Qaidam Basin, Qinghai Province are collected in 2014, and the tree ring chronologies are developed using three different detrending methods, contain spline function detrending method(SPL), negative exponential fitting detrending method(NEP) and regional curve detrending method(RCS). Combined temperature and precipitation data from Golmud Meteorological station in Qinghai, using correlation function and the response function method to analyze Populus euphratica radial growth response to climate in the different detrending methods. Studies have shown that the RCS Standardization chronology contain more climate information. The Populus euphratica chronology associated with monthly climatic factors indicate that the tree-ring chronologies no significant response to precipitation, and it has a good correlation with the mean temperature and mean maximum temperature in growing season, the highest correlation coefficient can reach to 0.411 (p <0.01), there have a best relationship between RCS Standardization chronology and mean maximum temperature from June to October. The mean maximum temperature in growing season may be a limiting factor of Populus euphratica radial growth on southern margin of Qaidam Basin, Qinghai Province, and it has physiological significance. The RCS chronology has a best response to climate in three different detrending methods