浑善达克沙地油松树轮宽度与气候因子的关系

为探讨不同径级油松对气候因子敏感度的差异,利用树木年轮学方法研究浑善达克沙地油松林40株油松样本建立的大径级(平均胸径34.5 cm)和小径级(平均胸径15.5 cm)油松的年轮宽度年表与气候因子的关系.结果表明:油松的平均敏感度与胸径大小呈线性负相关;不同径级油松的标准年表对气候因子的响应存在一致性,均表现为与春季温度正相关而与夏季温度负相关,并与降水呈正相关关系;其中与当年1~2月、当年9月的平均温度和最高温度呈显著正相关(P<0.05),与当年6月的平均温度和最高温度呈显著负相关(P<0.05);与当年1~2月和8~9月的最低温度呈显著正相关(P<0.05),与上年10月、当年5月和当年7月的降水呈显著正相关(P<0.05);同时,不同径级油松的标准年表对气候因子的响应还具有一定的差异性,即仅小径级油松表现为与当年6月的降水呈显著正相关(P<0.05),与当年7月的最高温度呈显著负相关(P<0.05).因此,利用树木生态学研究时应该考虑不同径级油松树轮年表对气候因子的响应差异.

Correlations Between Meteorological Factors and Tree-ring Width Index of Chinese Pine (Pinus tubulaeformis) in Hunshandake Sandy Area, China

To explore the radial growth of Chinese pine(Pinus tubulaeformis) with different diameter classes in response to meteorological factors,dendrochronological measurements were carried out to 20 large trees(LAG,mean diameter = 34.6 cm) and 20 small trees(SMA,mean diameter = 15.5 cm) of the species in Hunshandake sandy area,Inner Mongolia,China,and the correlations between the tree-ring chronology data and meteorological factors were studied.The results showed that the relationship between the mean sensitivity and DBH(diameter at breast height) was negatively correlated,while there existed similarities between the correlations of STD chronologies and the meteorological factors in that the STD chronologies were all positively correlated to the precipitation and spring temperatures,and negatively correlated to the summer temperatures.The STDs were positively correlated to the mean and maximum temperatures in January,February,September(P<0.05);and negatively correlated to the mean and maximum temperatures in June but positively correlated to the minimum temperature of January,February,August and September(P<0.05).They were positively correlated to the precipitation of October in the last year,and May and July of this year(P<0.05).On the other hand,the SMAs were positively correlated to the precipitation in June and negatively correlated to the maximum temperature in July(P<0.05).It was concluded that the differed correlations between the tree-ring chronologies and the meteorological factors among the trees of the different diameter classes should be taken into consideration indendrochronological studies.