模拟穿透雨减少对锐齿栎(Quercus aliena var. acuteserrata)树干液流密度的影响

Abstract

PDF HTML阅读 XML下载 导出引用 引用提醒 模拟穿透雨减少对锐齿栎(Quercus aliena var. acuteserrata)树干液流密度的影响 DOI: 10.5846/stxb201903060423 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国际竹藤中心基本科研业务费专项基金项目（1632018002，1632018004，1632017016）；国家重点研发计划（2018YFC0507301） Effects of manipulated throughfall reduction on sap flux density of Quercus aliena var. acuteserrata Author: Affiliation: Fund Project: International Bamboo and Rattan Center"s special funds for basic research and operation fees;National Key R&D Program 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:降水格局变化是全球气候变化的重要特征之一，未来气候变化下，较为频繁和严峻的干旱将威胁地球中纬度部分地区的森林，但森林植被如何响应季节性干旱胁迫及其机制尚不清楚。北亚热带-暖温带过渡区分布着以锐齿栎（Quercus aliena var. acuteserrata）为优势树种的落叶阔叶林，研究其水分蒸腾代谢过程对干旱的响应是评估气候变化对过渡区天然落叶阔叶林生态系统水碳影响的关键科学问题。在典型的锐齿栎天然林中通过开展模拟穿透雨减少大型野外实验，采用Granier热扩散式探针技术监测锐齿栎树干液流密度的动态变化，研究了不同径级锐齿栎树干液流密度对模拟干旱的响应规律。结果表明：（1）穿透雨减少对树干液流密度的影响呈现季节变异。在7月份，林内穿透雨减少显著降低了锐齿栎的树干液流密度，但生长季后期的10月份林内穿透雨减少反而使锐齿栎树干液流密度显著升高。（2）不同径级的锐齿栎树干液流密度在生长季内对干旱有不同的响应，特别是小径级的树干液流密度与其他径级有较多的不同。小径级的锐齿栎树干液流密度在5、7月份表现为减雨样地显著小于对照样地，在9、10月份则表现为减雨样地显著大于对照样地。中径级的锐齿栎树干液流密度在5、10月份表现为减雨样地显著大于对照样地，在7月份则表现为减雨样地极显著小于对照样地。大径级的锐齿栎树干液流密度在6、7月份表现为减雨样地显著小于对照样地，在10月份则表现为减雨样地显著大于对照样地。 Abstract:The change in precipitation pattern is one of the characteristics of global climate change. Some regions at mid-latitude might experience more frequent and severe drought. However, it is unclear how the precipitation change will affect the forest vegetation in those regions. Amongst, Quercus aliena var. acuteserrata is the dominant canopy tree species of deciduous broad-leaved forests in the warm temperate zone of middle China. Understanding the evapotranspiration responses of Q. aliena to drought induced by climate change is crucial to elucidate carbon-water coupling process. In order to explore the warm-temperate deciduous broad-leaved forest response to precipitation change, a manipulated throughfall reduction experiment was conducted in Baotianman National Nature Reserve since 2013. The Granier thermal diffusion probe (TDP) was used to measure the dynamic change of sap flux density of Q. aliena. The results showed that the throughfall reduction had significant effects on the sap flux density (Js) during the growing season. Firstly, the throughfall reduction significantly reduced the sap flux density of Q. aliena in July. However, in the late growing season (October), the throughfall reduction increased the sap flux density of Q. aliena significantly. Therefore, the sap flux density of Q. aliena differently responded to the throughfall reduction among months during the growing season. Secondly, the sap flux density of Q. aliena of different tree sizes showed different responses to drought during the growing season, especially the small trees (diameter at breast height, DBH≤21 cm) was different from that of medium (21 cm 参考文献 相似文献 引证文献