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矮曲林是山地森林带在严酷的自然环境影响下发展演化而成的特殊植物群落,对中国山地植被和垂直带的研究具有重要的地理和生态意义。本文选择20世纪30年代以来在国内外文献中发表的52个矮曲林数据,结合Worldclim气候数据等,对中国矮曲林的类型和分布及其相应的气候条件进行了研究。结果表明:1中国的矮曲林主要包括山顶苔藓矮曲林、寒温性偃松矮曲林和岳桦矮曲林3类;其中,山顶苔藓矮曲林主要分布于秦巴山区以南的山地,而偃松矮曲林和岳桦矮曲林主要分布于东北地区。2山顶苔藓矮曲林主要由亚热带、热带地区的常绿阔叶林在山顶或山脊受山顶效应等的影响演化而来;而寒温性矮曲林主要由寒温性针叶林或针阔混交林在山顶或山脊条件下长期演化而来。山顶苔藓矮曲林自东向西随地势升高,其分布的海拔高度也逐渐升高;寒温性偃松矮曲林和岳桦矮曲林分布高度自南向北逐渐降低。3矮曲林分布在气候林线以下的山地,其气候条件足以支撑山地森林的发育,但由于山顶效应的存在(如强风、气候干冷或湿冷及土壤贫瘠等),只能发育矮曲林而非垂直地带性的山地森林。4中国东南部的很多山地高度小于3000 m,山顶效应明显,矮曲林广泛发育,造成了假林线的普遍存在。
Stirrup forest is a special plant community evolved from the mountain forest belt under the influence of harsh natural environment. It has important geographical and ecological significance for the study of mountain vegetation and vertical belt in China. In this paper, we selected 52 shortetrim forest data published in the domestic and foreign literature since the 1930s, combined with the Worldclim climatic data, studied the type and distribution of Chinese ditributulin and its corresponding climatic conditions. The results showed that: 1 The Chinese ditribogolin forest mainly includes the mound dwarfing forest, the cold-temperate Pinus thunbergii forest and the dwarfing song dwarfing forest. Among them, the top moss dwarfing forest is mainly distributed in the south of the Qinling-Bashan Mountains Mountain, while Yan Song dwarf song song and song Cheng dwarf songlin mainly distributed in the northeast region. 2 Peak moss dysenne forest is mainly evolved from the subtropical and tropical evergreen broad-leaved forests on the mountaintops or ridges by the mountaintop effect; while the cold-temperate dwarf songlin mainly by cold temperate coniferous forest or needle-wide Mixed forests have evolved over the long term under the conditions of hills or ridges. The top moss dwarf songlin increased with the rise of terrain from east to west, and the altitude of its distribution also gradually increased. The distributing height of cold-temperate Pinus sylvestris var. Meyernensis and Betula ermanii decreased gradually from south to north. The dwarfing forests are distributed in mountainous areas below the climatic forest, and their climatic conditions are sufficient to support the development of mountain forests. However, dwarfing forest can only develop due to the effect of hilltops (such as strong winds, dry or humid climates and poor soil) Non-vertical zonal mountain forest. 4 Many mountainous areas in southeastern China have a height of less than 3000 m, with a clear top effect and extensive development of dwarf trichosanthes, resulting in the widespread presence of fake forest.