基于针茅属植物的系统发育探究中国草原的演化历史

发布时间：2018-06-29 07:49

本文选题：针茅属 + 中国草原　；参考：《内蒙古大学》2017年硕士论文

【摘要】：草原是全球生态系统的重要组成部分,面积最大的是欧亚草原。中国草原从东北平原经内蒙古高原、鄂尔多斯高原、黄土高原直达青藏高原的南缘,是欧亚草原的重要组成部分。草原生态系统的研究引起广泛的关注,但是有关于我国草原形成及演化进程,是目前研究较少的一个环节。针茅属植物广泛分布于整个欧亚草原,其作为建群种构建的针茅草原是欧亚草原的气候顶级群落,针茅属植物在草原形成的过程中起着至关重要的作用。通过研究针茅属的分化演变历史对研究中国草原的演化来说是一个非常好的途径。因此本研究基于针茅属植物的分子学证据,较为深入的研究了中国针茅属植物与中国主要草原的起源及演化历程。得到以下结论:(1)针茅属植物在28MaB.P.(百万年前)与外类群分歧而起源,22Ma B.P.在内蒙古中部开始分化,该属的物种集中形成期在9-2.61MaB.P.期间;(2)针茅属植物在内蒙古中部形成以后,沿四条路线进行扩散:在16MaB.P.时,由内蒙古中部扩散至祁连山,青海和西藏西部地区,并于ll-6MaB.P.时,由西藏西部逐渐扩散至东部;在12MaB.P.时,由内蒙古中部扩散至贺兰山地区;在8MaB.P.时,由内蒙古中部地区扩散至新疆地区;在4MaB.P.时,由内蒙古中部扩散至内蒙古东部地区;(3)针茅属植物在草原形成的过程中起着至关重要的作用,草原发生演化的过程是伴随着针茅属植物的演化发展历程来进行的。因此,基于针茅属的扩张路线,我们可以大致推测出中国草原的形成先后顺序为:内蒙古中部--祁连山--青海--西藏西部--贺兰山--新疆--西藏中部--西藏东部--内蒙古东部,最终在4MaB.P.时形成今天的草原景观;(4)青藏高原的隆起对针茅属植物与中国草原的起源与演化起到重要推动作用。
[Abstract]:Grassland is an important part of global ecosystem, the largest area is Eurasian grassland. The steppe of China is an important part of the Eurasian steppe, which passes through the Inner Mongolia Plateau, Ordos Plateau and Loess Plateau from the Northeast Plain to the southern margin of the Qinghai-Tibet Plateau. The study of grassland ecosystem has attracted wide attention, but there is less research on the formation and evolution of grassland in China. Stipa is widely distributed in the whole Eurasian steppe. As a constructive species, the Stipa is the top climatic community of Eurasian steppe, and it plays an important role in the process of grassland formation. It is a good way to study the evolution of Chinese steppe by studying the history of the differentiation and evolution of Stipa. Therefore, based on the molecular evidence of the genus Stipa, the origin and evolution of the genus Stipa in China and the main steppe in China were studied in depth. The main conclusions are as follows: (1) in 28 Ma B. P. (millions of years ago) originated from the divergence with the exotaxa (22 Ma B.P.). In the middle part of Inner Mongolia, the species of the genus began to differentiate, and the species of the genus began to form in 9-2.61 MaB.P. (2) after its formation in the central part of Inner Mongolia, the genus Stipa diffused along four routes: at 16 Ma B. P. From central Inner Mongolia to Qilian Mountains, Qinghai and western Tibet, and ll-6MaB.P. It was gradually spread from western Tibet to eastern Tibet. From the central part of Inner Mongolia to Helan Mountain area, and from 8MaB.P. From the central part of Inner Mongolia to Xinjiang, and from 4MaB.P. From the middle of Inner Mongolia to the eastern part of Inner Mongolia. (3) the genus Stipa plays an important role in the process of grassland formation. The process of grassland evolution is accompanied by the evolution of Stipa. Therefore, based on the expansion route of Stipa, we can roughly speculate that the order of grassland formation in China is as follows: central Inner Mongolia-Qilian Mountains-Qinghai-Western Tibet-Helan Mountain-Xinjiang-Central Tibet-East Tibet-Eastern Inner Mongolia. Finally, 4 MaB.P. (4) the uplift of Qinghai-Xizang Plateau plays an important role in promoting the origin and evolution of the genus Stipa and the grassland of China.
【学位授予单位】：内蒙古大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S812

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