欧亚大陆高山林线温度的差异性分析  

Temperature differences of timberlines in the Eurasian continent

作　　者：赵芳[1] 朱连奇[1] 张百平[2,3] 韩芳 姚永慧 曹艳萍[1] 

机构地区：[1]河南大学环境与规划学院,开封475004 [2]中国科学院地理科学与资源研究所资源与环境信息系统国家重点实验室,北京100101 [3]江苏省地理信息资源开发与利用协同创新中心,南京210023 [4]山东理工大学建筑工程学院,淄博255000

出　　处：《生态学报》2018年第1期263-272,共10页Acta Ecologica Sinica

基　　金：国家重点基础研究计划(973)(2015CB452702);国家自然科学基金项目(41601091;41671090;41401111)

摘　　要：尽管全球高山林线的形成在理论上具有相似的温度条件,但是由于不同气候区林线生态环境的复杂性,林线位置的热量状况具有明显的差异。为了探索林线温度的差异性和复杂性,从公开发表的文献中收集了欧亚大陆410个林线数据,基于公用的World Clim气候数据集计算了与林线存在有关的7个热量指标。结果表明:(1)欧亚大陆高山林线生长季温度变化较小,具有相对的稳定性;(2)不同气候区影响林线高度的主导气候因子变化较大,热带湿润气候区为年生物温度4.63℃、温暖指数21.72℃·月、年均温3.56℃,但在亚热带地中海气候区分别为年生物温度5.25℃、温暖指数29.37℃·月、年均温4.46℃;(3)通常认为的林线指示温度—最热月温度10℃仅存在温带海洋性气候区、亚寒带海洋性气候区和高原温带地区,年生物温度3℃仅存在亚寒带气候区,温暖指数15℃·月仅存在亚寒带大陆性气候区。这揭示了欧亚大陆及不同气候区林线温度的稳定性和变化性,有助于人们全面的认识林线的生态环境特征,深入探索复杂环境条件下林线高度变化的生态机理。Timberline, the transitional ecosystem between the uppermost closed montane forests and the treeless alpine meadows, is sensitive to climate change and has long attracted the attention of scientists in many fields of study. Previous research on timberline commonly focused on the relationships between timberline elevation and temperature factors to identify the common controlling factors. Many isotherms thus have been proposed to predict the existence of timberlines in mountain regions. Those isotherms commonly used include the mean temperature of 10℃ for the warmest month （MTWM）, mean annual biotemperature （ABT） of 3℃, warmth index （WI） of 15℃·month, etc. However, actual geographical distribution of timberlines often deviates from these isotherms. For examples, MTWM could be as low as 5-6℃ at tropical timberlines and as high as 15.8℃ in Norway. Moreover, a certain type of isotherm cannot reflect or completely cover up the diversity and complexity of timberline environment in different regions. To explore the temperature diversity of timberlines, we compiled data for 410 timberline sites in the Eurasian continent from published literatures; calculated seven thermal variables from published WorldClim dataset that are potentially associated with timberline elevation; and analyzed the variation of these climatic factors. The results reveal that：1） although all temperature variables at timberline positions in the Eurasian continent have wide ranges, MTWM, ABT and WI, which are the representative climate indexes of growing season temperature, have a relatively narrow range. For example, MTWM varies from 6.95℃ to 15.64℃. This indicates that growing season temperatures are key climatic indexes for timberline existence in the Eurasian continent. 2） Temperature indicators associated with timberline elevation vary greatly across different climate zones. In the tropical humid zone, ABT is 4.63℃, WI 21.72℃·month, AMT （annual mean temperature） 3.56℃; in the subtropical humid zone, AB

关 键 词：林线高度 欧亚大陆 气候因子 温暖指数 年生物温度 

分 类 号：S718.51[农业科学—林学]