北京西山栓皮栎人工林径向生长对干旱事件的响应  

Response of radial growth of the Chinese cork oak plantation forest to drought events in Xishan mountain,Beijing

作　　者：蔡林豆 刘勇[1] 张瑞瑶 王彦超 刘佳鹏 程如林 薛柳 CAI Lindou;LIU Yong;ZHANG Ruiyao;WANG Yanchao;LIU Jiapeng;CHENG Rulin;XUE Liu(College of Forestry,Beijing Forestry University,Beijing 100083,China;Beijing Xishan National Forest Park,Beijing 100083,China)

机构地区：[1]北京林业大学林学院,北京100083 [2]北京市西山国家森林公园,北京100083

出　　处：《中南林业科技大学学报》2025年第1期130-139,共10页Journal of Central South University of Forestry & Technology

基　　金：“十三五”国家重点研发计划项目(2016YFD0600403);北京园林绿化增彩延绿科技创新工程项目(CEG-2015)。

摘　　要：【目的】为阐明同一立地条件下不同径级树木产生径向生长差异的原因,分析限制其生长的主要气候因子以及对不同干旱事件的响应,并结合水力性状解释这种差异。【方法】以栓皮栎人工林为研究对象,不同径级树木各选择45棵,采集年轮资料并计算树轮宽度特征,研究生长与气候因子之间的关系以及对干旱事件的响应,同时采集叶片进行PV曲线分析,并将其与生态弹性能力指标进行相关性分析。【结果】降水量是限制不同径级树木生长的主要因子,径向生长大多受上一年6、11月和当年4、5月的影响,主要导管特征多受上一年和当年春季、夏季、秋季的影响。在干旱事件中,劣势木的抵抗力最强并且比叶面积最大(240 cm^(2)/g),其恢复弹力与膨压损失点呈显著正相关,优势木的恢复弹力最强并且膨压损失点(2.2 MPa)、饱和渗透势(1.7 MPa)、细胞壁弹性模量(10.0 MPa)最大,其膨压损失点与恢复弹力均呈显著负相关。【结论】不同径级树木响应策略各异,优势木可以更加快速地在干旱事件中通过补充蒸腾丧失水分、缓冲叶片水势波动恢复生长,从而在径向生长中占据优势地位,而劣势木尽管有着强抵抗力,但其水力功能并没有带来过多资源,导致其无法应对胁迫风险。未来应有针对性地进行抚育和管理,增强整个林分的抗旱能力。【Objective】To elucidate the causes of radial growth differences among trees of different diameter classes under the same site conditions,to analyze the main climatic factors limiting their growth and their responses to different drought events,and to explain such differences by combining hydraulic traits.【Method】The Chinese cork oak plantation forest was used as the research object,45 trees of different diameter classes were selected,the tree ring data were collected and the chronology statistics were calculated to study the relationship between growth and climatic factors as well as the response to the drought events,while the leaves were collected for the PV curve analysis and correlated with the index of ecological resilience capacity.【Result】Precipitation is the main factor limiting the growth of trees of different diameter classes,radial growth is mostly influenced in June and November of the previous year and April and May of the current year,and major conduit characteristics are mostly influenced by spring,summer,and fall of the previous and current year.During the drought event,inferior trees was the strongest resistant and had the largest specific leaf area(240 cm^(2)/g),and its resilience was significantly and positively correlated with the leaf water potential at turgor loss,whereas dominant trees was the strongest resilience and had the largest leaf water potential at turgor loss(2.2 MPa),osmotic potential at full hydration(1.7 MPa),and bulk tissue modulus of elasticity(10 MPa),and its leaf water potential at turgor loss were significantly and negatively correlated with the resilience.【Conclusion】The response strategies of trees of different diameter classes varied,and the dominant trees could more rapidly recover growth by replenishing water lost through transpiration and buffering fluctuations in leaf water potential during drought events,thus occupying an advantageous position in radial growth,whereas the inferior trees,despite its strong resistance,did not bring too many resources

关 键 词：栓皮栎 径向生长 气候响应 水力性状 

分 类 号：S728.2[农业科学—林木遗传育种]