祁连山青海云杉木材密度对气候变化的响应

为探明木材密度对气候变化的响应,以祁连山中部下限青海云杉为研究对象,利用Silviscan-3测定了青海云杉的木材密度,根据树木年轮气候学的标准方法建立了年轮密度、早材密度、晚材密度、最大密度、最小密度年表,分析了各个木材密度年表与月平均温度、最高温度、最低温度和月降雨量的关系。结果发现：木材密度与温度正相关,与降雨量...

Response of wood density of Picea crassifolia to climate change in Qilian Mountains of northwestern China

To investigate the response of wood density to climate change, wood density of Picea crassifolia trees at lower tree line in the middle Qilian Mountains, northwestern China was measured using Silviscan-3. Chronologies of annual, earlywood, latewood, maximum and minimum density were established by dendrochronological methods. Relationships of chronologies to monthly mean, maximum, minimum temperatures and monthly precipitation were analyzed. The results indicated that wood density of P.crassifolia trees positively correlated with temperatures and negatively correlated with precipitation. Annual and earlywood density significantly correlated with monthly mean temperatures in June to September, with monthly maximum temperatures in June, July and September, and with monthly minimum temperatures in October in previous year and in July and September in current year. Minimum density significantly correlated with temperature in June to August, with monthly maximum temperatures in June and July, and with monthly minimum temperatures in July. Annul density significantly correlated with precipitation in March. Earlywood and minimum density significantly correlated with precipitation in June. Latewood and maximum density did not show significant relationships with temperature and precipitation, latewood density was less sensitive to climate than earlywood density. Those results indicate that temperature has directly influence and precipitation has indirectly impact on wood density, temperature in summer is main climate factor influencing wood density of P.crassifolia in Qilian Mountains, northwestern China.