摘要
基于黄土高原中部地区降水梯度上(绥德447mm,延安531mm,宜君603mm)的乔灌木年轮材料,通过树木年轮气候学方法分析了不同降水条件下,乔木刺槐(Robinia pseudoacacia)、山杏(Armeniaca sibirica),灌木酸枣(Ziziphus jujuba)、白刺花(Sophora davidii)径向生长的气候敏感性差异。结果表明:(1)绥德、宜君酸枣标准年表的相关统计参量明显偏低,个体生长一致性较差,年轮材料中包含的气候信息较少,这表明绥德和宜君地区的酸枣对本地气候条件已高度适应,径向生长受气候影响较小。(2)刺槐、山杏、酸枣、白刺花均在森林草原过渡带(延安)表现出较高的气候敏感性,气候要素对各物种径向生长的解释率在该地区最高。除绥德、宜君酸枣外,各样点的乔灌木气候--生长关系均存在“时滞效应”。整体上研究区内酸枣气候敏感性最差。在绥德和宜君地区,灌木气候敏感性明显弱于乔木。(3)乡土物种山杏、酸枣、白刺花在三个采样点均对长期干旱胁迫不敏感,对当地环境具有较强的生态适应性。人工物种刺槐在延安地区,从上年生长季末至当年生长季结束持续对干旱胁迫响应敏感,而在绥德和宜君地区则对干旱胁迫不敏感。刺槐、山杏、白刺花在宜君地区与温度的响应特征整体上发生明显趋势转换,温度对刺槐、白刺花的负反馈减弱正反馈增强,而对山杏的正反馈减弱负反馈增强。
Using tree and shrub ring materials from precipitation gradients(Suide:447 mm,Yan′an:531 mm,and Yijun:603 mm)in the central of the Loess Plateau,the climatic sensitivity of radial growth of Robinia pseudoacacia,Armeniaca sibirica,Ziziphus jujuba,and Sophora davidii under different precipitation conditions was analyzed by methods of dendroclimatology.The results are as follows:(1)the standard chronology of Ziziphus jujuba in Suide and Yijun had lower statistical parameters,lower individual growth consistency,and less climate information in the tree-ring material.It indicated that Ziziphus jujuba in Suide and Yijun County were highly adapted to local climatic conditions and its radial growth was less affected by climate.(2)Robinia pseudoacacia,Armeniaca sibirica,Ziziphus jujuba,and Sophora davidii all showed higher sensitivity to climate in forest-steppe transition zone(Yan′an),and the explanation rate of climate factors to radial growth of species was the highest in this area.Except for Ziziphus jujube in Suide and Yijun,there were time-lag effects in the climate-growth relationship of trees and shrubs at different sample sites.On the whole,the climate sensitivity of Ziziphus jujube was the weakest.In Suide and Yijun,the sensitivity of shrubs to climate was significantly lower than that of trees.(3)Natural species Armeniaca sibirica,Ziziphus jujuba,and Sophora davidii were not sensitive to long-term drought stress under the three sample sites,which showed strongly ecological adaptability.The response characteristics of Robinia pseudoacacia,Armeniaca sibirica,and Sophora davidii in Yijun showed a trend shift.The negative feedback of temperature to Robinia pseudoacacia and Sophora davidii decreased and the positive feedback of temperature increased,while the positive feedback of temperature to Armeniaca sibirica decreased and the negative feedback of temperature increased.
作者
刘杰
李宗善
梁海斌
LIU Jie;LI Zongshan;LIANG Haibin(State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China;College of Resources and Environment,University of Chinese Academy of Sciences,Beijing 100049,China;National Observation and Research Station of Earth Critical Zone on the Loess Plateau in Shaanxi,Xi′an 710061,China;Institute of Geographical Science,Taiyuan Normal University,Jinzhong 030619,China)
出处
《生态学报》
CAS
CSCD
北大核心
2024年第3期1203-1220,共18页
Acta Ecologica Sinica
基金
国家自然科学基金重大项目(41991233)
国家自然科学基金面上项目(42071125,42101104)。
关键词
黄土高原
降水梯度
径向生长
气候敏感性
乔灌木
the Loess Plateau
precipitation gradient
radial growth
climate sensitivity
tree and shrub
