黄土高原健康和衰退刺槐林径向生长对气候的响应  

The climate⁃response pattern of radial growth for the health and decline black locust plantations on the Loess Plateau,China

作　　者：李宗善 陈维梁[1] 焦磊 张钦弟[4] 李兆林 王聪 高光耀 卫伟[1,2] 孙婧雅 白应飞 LI Zongshan;CHEN Weiliang;JIAO Lei;ZHANG Qindi;LI Zhaolin;WANG Cong;GAO Guangyao;WEI Wei;SUN Jingya;BAI Yingfei(State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China;National Observation and Research Station of Earth Critical Zone on the Loess Plateau in Shaanxi,Xi′an 710061,China;School for Geography and Tourism,Shaanxi Normal University,Xi′an 710119,China;College of Life Sciences,Shanxi Normal University,Taiyuan 030032,China;Grain to Green Project Management Office of Yan′an Government,Yan′an 716000,China)

机构地区：[1]中国科学院生态环境研究中心城市与区域生态国家重点实验室,北京100085 [2]陕西黄土高原地球关键带国家野外科学观测研究站,西安710061 [3]陕西师范大学地理科学与旅游学院,西安710119 [4]山西师范大学生命科学学院,太原030032 [5]延安市退耕还林工程管理办公室,延安716000

出　　处：《生态学报》2024年第2期757-769,共13页Acta Ecologica Sinica

基　　金：国家重点研发计划项目(2022YFF130040003,2022YFF0801802);国家自然科学基金面上项目(42071125,41877539)。

摘　　要：全球气候变化导致的区域森林生长衰退和死亡普遍发生,并对森林生态系统结构和组成以及主要生态系统服务功能产生重要影响,然而相关研究在国内还显偏少。根据黄土高原延安羊圈沟小流域人工刺槐林健康和衰退个体分别构建了刺槐健康和衰退树轮年表,并对人工刺槐林健康和衰退年表特征及对气候响应敏感性进行了对比分析。结果表明刺槐衰退年表质量较低,其年表统计参量,包括平均敏感度、样芯间相关系数、信噪比和样本群体代表系数均要低于刺槐健康年表。刺槐衰退年表在生活史早期(1985—2007年)与生长健康年表的波动趋势相类似,而在生活史晚期(2008—2016年)与健康年表指数出现生长分离现象,生长速率明显偏低。年表与气候要素响应分析表明刺槐生长衰退年表对气候要素响应敏感性要低于刺槐生长健康年表,但是两者均含有干旱胁迫气候信号,主要体现在与温度呈负相关关系,与降雨和干旱指数的正相关关系。年表与极端气候年份的时序叠加分析表明,生长健康和衰退年表对极端干旱年份响应敏感性均较高,表明极端干旱胁迫条件对刺槐生长健康和衰退个体均有抑制性影响;生长健康年表对极端湿润年份响应敏感性明显高于衰退年表,表明刺槐健康个体比衰退个体更能有效利用湿润年份有利条件,而具有较高的生长速率。研究揭示出黄土高原健康和衰退刺槐个体生长趋势变化及对气候响应敏感性均存在明显差异性,将为气候变化背景下人工刺槐林生长衰退和死亡预测模型建立提供科学依据,因而对黄土高原人工刺槐林生态恢复和保护及可持续经营具有科学价值。Episodes of forest mortality have been observed worldwide associated with climate change,which has affected forest structure and species composition,as well as the essential ecosystem services and functions.There is increasing body of empirical studies to elucidate the spatiotemporal pattern and inherent driving mechanisms of forest growth decline and tree mortality,but related studies in China have not received much attention.Tree-ring width chronologies of growth health and decline black locust(Robinia pseudoacacia)plantations in the Yangjuangou catchment in the central Loess Plateau of China were constructed,and the differences of climatic sensitivity in tree-ring annual data of growth health and decline black locust plantations were analyzed.The results showed that the quality of tree-ring chronology for growth decline black locust was lower than growth health chronology,representing the comparatively lower value of several statistical parameters,including mean inter-series correlation(Rbar),mean sensitivity(MS),signal-to-noise ratio(SNR),and express population signal(EPS).The growth health and decline chronologies of black locust had similar growth fluctuations in the early stage of lifespan(from 1985 to 2007),but two series had increasingly diverged at the late stage of lifespan(from 2008 to 2016)as tree-ring indices of growth decline trees had progressively fallen.The analysis of climate-growth response indicated the radial growth of growth health and decline black locust trees were both mainly controlled by drought stress,but the climatic sensitivity of growth decline trees was relatively lower and the correlations with different climatic variables(temperature,precipitation and Palmer Drought Severity Index)were also comparatively weaker.Superposed Epoch Analysis(SEA)indicated that ring width variance of growth decline and growth healthy black locust trees were both sensitive to extreme drought years,indicating that extreme drought events could significantly inhibit radial increment for black locust trees

关 键 词：树木年轮 气候响应 生长衰退 人工刺槐林 黄土高原 

分 类 号：S71[农业科学—林学]