摘要
黄土高原半干旱地区人工林生长受水分和温度影响显著,坡向作为重要的立地因子,在水热条件再分配中起到了决定性的作用。利用树木年轮学方法测定了1995—2020年六盘山叠叠沟小流域阴坡、半阴坡和阳坡的华北落叶松(Larix gmelinii var.principis⁃rupprechtii)人工林优势木逐年树轮宽度,建立树轮宽度标准年表(STD)和差值年表(RES)分析不同坡向林木生长特征及对气候响应的敏感性差异。研究结果表明:(1)各坡向优势木年表质量表现为阴坡最好、阳坡最差。(2)阴坡树木受最高气温和最低气温抑制作用显著(上年6、11月和当年7月);半阴坡树木与当年7月平均气温显著负相关;阳坡树木与平均气温的相关性低。(3)不同坡向树木均与上年8月降水量显著正相关,且阳坡树木对降水量的响应敏感性高于阴坡和半阴坡;半阴坡树木还受当年7月相对湿度的促进作用。(4)阳坡树木对干旱胁迫的响应敏感性高于半阴坡和阴坡,其中气象因素对阴坡树木径向生长变化的解释率最低。综上所述,六盘山半干旱区华北落叶松对气候响应的敏感性较高,且阳坡主要受降水量影响,阴坡受最高气温和最低气温影响较大,半阴坡则受温度和降水的共同调节。若发生干旱事件,阳坡树木径向生长下降幅度要远高于阴坡和半阴坡。结果为黄土高原土石山区华北落叶松人工林保护和可持续经营提供科学依据。
The growth of plantations in semi⁃arid areas of the Loess Plateau is significantly affected by water and temperature.The slope aspect,as an important site factor,plays a decisive role in the redistribution of water and heat conditions.In this study,dendrodological methods were used to determine the annual tree ring width of dominant Larix gmelinii var.principis⁃rupprechtii plantations in shady slope,semi⁃shady slope and sunny slope in Diediegou small watershed of Liupan Mountain from 1995 to 2020.Tree ring width Standard chronology(STD)and Residual chronology(RES)were established to analyze the growth characteristics of the dominant Larix gmelinii var.principis⁃rupprechtii and its sensitivity to climate response.The results showed that:(1)the chronology quality of Larix gmelinii var.principis⁃rupprechtii in each slope direction was the best on the shady slope and the worst on the sunny slope.(2)The trees on the shady slope were significantly inhibited by the maximum temperature and the minimum temperature(June,November of last year and July in the current year),and the trees on the semi⁃shady slope had a significant negative correlation with the average temperature in July of that year,while the trees on the sunny slope had a low correlation with the average temperature.(3)The trees on different slope directions were significantly positively correlated with precipitation in August of last year,and the response sensitivity of the trees on the sunny slope to precipitation was higher than that of the shady slope and the semi⁃shady slope.In addition,the relative humidity in July of the same year also promoted the growth of trees on semi⁃shady slope.(4)The response sensitivity of sunny slope to drought stress was higher than that of shady slope and semi⁃shady slope and the interpretation rate of tree radial growth by climate factors was the lowest in the shady slope.In conclusion,Larix gmelinii var.principis⁃rupprechtii with different slope directions in the semi⁃arid area of Liupan Mountain has a high sensitivity to climate response,the sunny slope is mainly affected by precipitation,the shady slope is affected by the maximum and minimum temperature,and the semi⁃shady slope is jointly regulated by temperature and precipitation.In case of drought events,the decline of radial growth of Larix gmelinii var.principis⁃rupprechtii on the sunny slope was much higher than that on the shady slope and semi⁃shady slope.The results provide a scientific basis for the protection and sustainable management of Larix gmelinii var.principis⁃rupprechtii plantation on the Loess Plateau.
作者
王巍樾
万艳芳
白雨诗
王冬梅
于澎涛
王彦辉
刘亚玲
李宗善
WANG Weiyue;WAN Yanfang;BAI Yushi;WANG Dongmei;YU Pengtao;WANG Yanhui;LIU Yaling;LI Zongshan(School of Soil and Water Conservation,Beijing Forestry University,Key Laboratory of Soil and Water Conservation and Desertification Combating of Ministry of Education,Beijing 100083,China;Key Laboratory of Forestry Ecology and Environment of State Forestry Administration Institute of Forest Ecology,Environment and Protection,Chinese Academy of Forestry,Beijing 100091,China;Research Center of Eco-Environment,Chinese Academy of Sciences,Beijing 100085,China)
出处
《生态学报》
CAS
CSCD
北大核心
2024年第16期7290-7300,共11页
Acta Ecologica Sinica
基金
“十四五”国家重点研发课题(2022YFF1300404)
国家自然科学基金(U21A2005,U20A2085)。
关键词
树木年轮
年表
气候响应
华北落叶松
黄土高原
tree ring
chronology
climate response
Larix gmelinii var.principis⁃rupprechtii
the Loess Plateau
