摘要
大兴安岭是我国气候变暖的敏感地区。为比较在升温过程中不同地区落叶松(Larix gmelinii)径向生长对温度的响应差异,在大兴安岭主脉南段、中段和北段进行树木年轮取样,建立了各点年轮宽度年表,根据年表第一主成分载荷系数分类最终合成南部、中部和北部各区年轮指数。利用相关函数分析了落叶松径向生长与温度变化的关系,结合主成分分析对比了不同地区树木年轮宽度变化对温度的响应差异。结果表明:落叶松径向生长对温度变化的响应呈现明显的南北差异(中部>北部>南部);南部年轮指数与上年11月到当年4月的平均温度显著相关,中部年轮指数与上年生长季(6–8月)和当年3–10月的平均温度显著负相关,北部年轮指数与生长季前(4–5月)的平均温度极显著正相关。气候变暖背景下,高温引起的区域暖干化使土壤水分成为限制落叶松径向生长的主要因子,土壤干旱程度加剧使落叶松生长对温度变化的响应增强。胸高断面积增量指示的落叶松生产力经历了从响应低温胁迫到响应高温引起的水分胁迫的转变。未来几十年,若温度持续升高,大兴安岭地区落叶松径向生长量将呈南部和中部降低、北部升高的趋势。
Aims The Da Hinggan Ling is amongst the areas in China susceptible to climate warming. The objective of this study is to determine the responses of radial growth to temperature variations in Larix gmelinii growing in different parts of the Da Hinggan Ling in the process of climate warming, by using dendrochronological techniques. Methods We collected tree-ring samples from the southern, the middle and the northern parts of the main Da Hinggan Ling, developed site-specific ring-width chronologies, and synthesized tree-ring indices of the southern, the middle and the northern parts of the study area according to the first principal component loading factors for each chronology. The relationships between radial growth in L. gmelinii and temperature variations were determined with correlation analysis, and the differences in the responses of radial growth to temperature variations among various parts were analyzed and compared with principle component analysis. Important findings There were notable discrepancies in the effects of temperature variations on radial growth in L. gmelinii between the southern and the northern parts of the study area（the middle part the northern part the southern part）. In the southern part, the mean monthly temperature between the previous November and April of the current year had a significant relationship with tree-ring indices（p〈0.05）. In the middle part, the mean monthly temperature during March and October of the current year had a significant relationship with tree-ring indices（p〈0.05）, and so did the mean monthly temperature during June and August of the previous year（p〈0.05）. The mean monthly temperature during April and May of the current year had a highly significant relationship with tree-ring indices in the northern part（p〈0.01）. This study suggests that the warmer and drier regional climate condition caused by elevated temperature has resulted in that soil moisture becomes the main factor limiting the radial growth, and the relationship between tr
作者
常永兴
陈振举
张先亮
白学平
赵学鹏
李俊霞
陆旭
CHANG Yong-Xing CHEN Zhen-Ju ZHANG Xian-Liang BAI Xue-Ping ZHAO Xue-Peng LI Jun-Xia LU Xu Tree-ring(Laboratory, College of Forestry, Shenyang Agricultural University, Shenyang 110866, China and Research Station of Liaohe-River Plain Forest Ecosystem, Chinese Forest Ecosystem Research Network, Changtu, Liaoning 112500, China)
出处
《植物生态学报》
CAS
CSCD
北大核心
2017年第3期279-289,共11页
Chinese Journal of Plant Ecology
基金
国家自然科学基金(41271066
31570632
41571094和41601045)
关键词
气候变暖
大兴安岭
落叶松
年轮宽度
径向生长
温度变化
敏感度
climate warming
the Da Hinggan Ling
Larix gmelinii
tree-ring width
radial growth
temperature variation
sensitivity
