芦芽山华北落叶松早晚材径向生长对气候变化响应的分离效应  

Response divergence of radial growth to climate change in earlywood and latewood of Larix principis-rupprechtii in Luya Mountain

作　　者：郭伊利 李书恒[1,2] 王嘉川 韩宜洁 GUO Yili;LI Shuheng;WANG Jiachuan;HAN Yijie(College of Urban and Environment Science,Northwest University,Xi’an 710127,Shaanxi,China;Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity,Xi’an 710127,Shaanxi,China)

机构地区：[1]西北大学城市与环境学院,陕西西安710127 [2]陕西省地表系统与环境承载力重点实验室,陕西西安710127

出　　处：《干旱区研究》2022年第5期1449-1463,共15页Arid Zone Research

基　　金：国家林业公益性行业科研专项(201304309);陕西省自然科学基金项目(2014JQ5172);黄土与第四纪地质国家重点实验室开放基金项目(SKLLQG1611)。

摘　　要：利用采自芦芽山3个海拔高度的华北落叶松(Larix principis-rupprechtii)年轮样芯建立树轮差值年表,采用树轮气候学的方法,以1984年/1985年为界,将树木整轮、早材和晚材差值年表与气候要素进行相关分析,探讨不同海拔华北落叶松径向生长对气候因子的响应,在1957—1984年和1985—2020年2个时段的异质性特征。结果显示:(1)芦芽山3个海拔树木早材和晚材径向生长变化在1957—2020年与研究区的气候变暖趋势难以拟合,与气温因子的响应发生了分离。(2)在1957—1984年,低海拔早材生长与气候因子未表现出显著的相关关系,生长季降水因子(6月降水量)对中高海拔早材生长具有明显的限制作用;进入1985—2020年,生长季降水因子(4月降水量)对低海拔早材的生长影响增强,中高海拔早材生长主要与1月降水量显著正相关,即生长季气候因子对中高海拔早材的生长限制作用减弱。(3)生长前养分积累对研究区华北落叶松树木晚材的生长至关重要:在1957—1984年,低海拔与中高海拔晚材宽度年表均与5月降水量呈显著正相关关系;在1985—2020年,树木晚材径向生长表现出与生长前气候因子(上一年11月,当年1月、3月、5月)的显著相关关系。(4)2个不同的时段内,低海拔早材生长模式的改变可能是气温升高带来的干旱胁迫造成的;而中高海拔早材生长模式差异有可能是由于气温升高缓解了中高海拔地区低温对早材生长的抑制作用。综上所述,随着全球气候变暖,芦芽山3个海拔华北落叶松树木早材和晚材生长在2个时段对于气候要素的响应特征、响应模式存在差异,与气候因子响应存在一定的“分离”现象,在今后区域气候重建工作中应考虑该地区树木生长的分离现象,保证重建工作的可靠性。Based on the annual ring cores of Larix principis-rupprechtii collected from three altitudes of Luya Mountain,the residual chronology of earlywood and latewood tree rings was established.Using the method of tree ring climatology and taking 1984/1985 as the boundary,heterogeneity characteristics of radial growth of earlywood and latewood of L.principis-rupprechtii at different altitudes in response to climate factors in 1957-1984 and 1985-2020 were discussed.The results showed that the following:(1)the radial growth changes of earlywood and latewood were difficult to fit the climate warming trend in the study area from 1957 to 2020,and the response to temperature is separated.(2)From 1957 to 1984,no significant correlation existed between low altitude and climate factors in the growth of earlywood.Precipitation during the growing season,which had a significant positive correlation with precipitation in March and negative correlation in June,had an obvious restrictive effect on the growth of earlywood at medium and high altitudes.The precipitation factors in the growing season from 1985 to 2020 had a significant positive correlation with precipitation in April and had an influence on the growth of earlywood at a low altitude,thereby enhancing it.The growth of earlywood at medium and high altitudes was mainly affected by precipitation in January,and the restrictive effect on the growth and development of earlywood at medium and high altitudes was weakened.(3)Nutrient accumulation before growth is very important for latewood growth of L.principis-rupprechtii:from 1957 to 1984.The chronology of latewood width at three altitudes showed a significant positive correlation with precipitation in May.From 1985to 2020,the radial growth of tree latewood was limited by the comprehensive factors of temperature and precipitation before growth in November of the previous year and January,March,and May of the current year.(4)In two different time periods,the change of the pattern of earlywood growth at a low altitude may have been

关 键 词：芦芽山 华北落叶松 海拔梯度 早材年轮宽度 晚材年轮宽度 气候变化 分离效应 

分 类 号：S791.22[农业科学—林木遗传育种]