黄土丘陵区小流域不同海拔刺槐径向生长对气候的响应差异  

Radial growth responses of black locust(Robinia pseudoacacia L.)to climate at different elevations in a Loess Plateau watershed

作　　者：刘亚玲 信忠保[1] 李宗善 买尔当·克依木 LIU Yaling;XIN Zhongbao;LI Zongshan;MAIERDANG Keyimu(College of Water and Soil Conservation,Beijing Forestry University,Beijing 100083,China;State Key Laboratory of Urban and Regional Ecology,Research Center for Eco-Environmental Sciences,Chinese Academy of Sciences,Beijing 100085,China)

机构地区：[1]北京林业大学水土保持学院,北京100083 [2]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

出　　处：《生态学报》2023年第24期10119-10130,共12页Acta Ecologica Sinica

基　　金：国家自然科学基金项目(42177319,41877539)。

摘　　要：为明确黄土高原丘陵区第三副区典型流域⁃甘肃天水罗玉沟流域刺槐生长过程及其与气候关系随海拔变化的规律。利用树木年代学方法分别建立高、中、低3个海拔刺槐的标准年表,并分析不同海拔刺槐径向生长过程以及对气候变化的响应。研究结果表明:(1)中、低海拔刺槐径向生长与温度因素多为负相关,而高海拔刺槐径向生长与温度因素多呈正相关。高海拔刺槐生长与上一年生长季(6月)、休眠期(当年3—4月)和当年生长季(6月)均温、最低温和最高温呈显著正相关,其中受最低温影响最显著;中、低海拔刺槐与上一年生长季和当年生长季的均温、最高温和最低温呈显著负相关,低海拔受均温影响显著。(2)随海拔升高,刺槐径向生长与降水和相对湿度的正相关呈降低趋势。低海拔刺槐生长与上一年生长季(7—9月)和当年生长季(6—9月)降水、相对湿度呈显著正相关,中海拔刺槐与当年生长季(6—9月)降水、相对湿度呈显著正相关,而高海拔刺槐生长与上一年生长季(6—7月)相对湿度呈显著负相关。(3)低海拔刺槐与上一年6月—当年10月帕默尔干旱指数(PDSI)呈显著正相关;中海拔刺槐与上一年6月和当年2—10月PDSI呈显著正相关;高海拔刺槐与上一年6—7月PDSI呈显著负相关。中、低海拔刺槐遭受干旱胁迫,限制树木生长。在气候暖干化背景下,罗玉沟流域中、低海拔刺槐受水分胁迫更加严重。在黄土丘陵区开展水土流失治理生物措施经营管理过程中,须注意刺槐林生长对气候响应的海拔差异。The purpose of this study is to determine the growth process of black locust(Robinia pseudoacacia L.)and its relationship with climate and elevation in the Luoyugou watershed of the Chinese Loess Plateau.Standard chronologies of black locust trees were measured at high,middle,and low elevation areas using dendrochronology method.The results indicated that the radial growth of black locust at middle and low elevation areas were negatively correlated with temperature factors;however,a positive correlation between temperature and radial growth of black locusts was observed at high elevation.In addition,black locust growth at high elevation was positively correlated with the mean temperature,minimum temperature,and maximum temperature during the previous year(June),dormant period(March—April),and current growing season(June).At middle and low elevation areas,the black locust growth were negatively correlated with the mean temperature,minimum temperature,and maximum temperature during the previous and current growing seasons.Black locust growth at low elevation was also significantly affected by the mean temperature.With elevation,a decreasing trend in the positive correlations between radial growth,precipitation,and relative humidity was observed.Black locust growth at low elevation was positively correlated with the precipitation and relative humidity during the previous year(July—September)and current growing season(June—September).At middle elevation,black locust growth was positively correlated with the precipitation and relative humidity during the current growing season(June—September),while the growth of black locust at high elevation was negatively correlated with the relative humidity during the previous growth season(June and July).At low elevation,black locust growth was positively correlated with the Palmer drought index(PDSI)from June of the previous year to October of the current year,whereas black locust growth at middle elevation was positively correlated with the PDSI in June of the previous

关 键 词：罗玉沟 刺槐 树木年轮 海拔梯度 气候响应 

分 类 号：S792.27[农业科学—林木遗传育种]