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鄂尔多斯是地球最原始的古陆之一。据古生物化石考证,鄂尔多斯已有六亿年之久的生命发展史,在距今三亿五千万年前就出现了繁茂的陆生植物,到处被漫无边际、郁郁葱葱的原始森林所覆盖。随着漫长的地质时代的变迁,绿色植物走过了蕨类植物、裸子植物、被子植物的由初等到高等的进化过程。鄂尔多斯由湖盆上升为高原,气候也由暖湿演变到干冷。自然环境的变化,导致了多数暖湿生植物遭到了毁灭,决定了这里的植物种类相对贫乏,植物多半由中生、旱生和超旱生种类组成。但值得提及的是有些植物种类如半日花、四合木、沙冬青、绵刺等都经过了漫长的历史性自然选择过
Erdos is one of the most primitive ancient land of the earth. According to paleontology fossils research, Erdos has a history of 600 million years of life. From the 350 million years ago, there appeared lush terrestrial plants covered in endless and lush primitive forests. With the long geological changes, the green plants have gone through the elementary to advanced evolution of ferns, gymnosperms and angiosperms. Erdos rose from lake basin to plateau, and climate changed from warm and humid to dry and cold. Changes in the natural environment led to the destruction of most of the warm and wet plant species, determines the relative abundance of plant species here, most of the plants by the Mesozoic, xerophytic and super-xerophytic species. However, it is worth mentioning that some plant species such as Half-day flowers, Tetraena, Asarum, Mianghua and so have gone through a long historic natural selection