Abstract

Steppes play an essential role in the vegetation of mountains of Southern Siberia (SS). However, they significantly differ in mountains of different climatic facies; these features are particularly pronounced in the spatial and phytocenotic structure of extrazonal steppe phenomena, namely, in ecotones of adjacent altitudinal belts. These steppe manifestations in landscapes are termed uburs in the geography of Inner Asia. The exposure combinations of forest and steppe communities in the vegetation of the mountain forest-steppe belt are most complex; the structure of this transitional belt is differentiated into two categories of subbelts: peristeppe and periforest ones, which, in turn, are differentiated into lower and upper variants. The role of steppes in the structure of vegetation of the exposure forest steppe in the mountains of a semihumid climatic facies is not limited by the boundaries of the peristeppe and periforest subbelts; steppe communities as extrazonal phenomena penetrate deep into the forest belt in the form of steppe and stepoid mosaics along ubur steps. The proportion of steppes is very low in the forest belt (from 20 to 5% or less). They include both developed steppe communities and stepoids with the inclusion of forest–shrub, subalpine, and mountain–tundra species. The imposition of the altitudinal and exposure gradients is expressed in the species and cenotic diversity of steppes, as well as in their spatial organization. Processes of speciation, often combined with populations of relict plant species, are intensively manifested in these original ecotones of mountain steppes.

中文翻译：

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西伯利亚南部山区的带外草原现象：空间组织的特征以及最新物种和新生代的中心

摘要

草原在西伯利亚南部（SS）山区的植被中起着至关重要的作用。但是，它们在不同气候相貌的山脉中差异很大。这些特征在带外草原现象的空间和植物群落结构中，即在相邻海拔带的过渡带中尤为突出。这些在草原上的表现被称为乌布在亚洲内陆地区。山区森林-草原带植被中森林和草原群落的暴露组合最为复杂。该过渡带的结构分为两类：亚带和近林带，后者又分为上，下变种。草原在半湿润气候带山区裸露森林草原植被结构中的作用不受围草原和林地亚带的限制；草原群落作为地带外现象沿ubur台阶以草原和阶梯状马赛克的形式深入森林带。在森林带中，草原的比例非常低（从20％到5％或更少）。它们包括发达的草原群落和阶地生物，其中包括森林灌木，亚高山和山地苔原物种。海拔梯度和暴露梯度的强加体现在草原的物种和物种多样性以及它们的空间组织中。在山地草原的这些原始生态交错带中，物种形成的过程通常与遗留植物物种的种群相结合。