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水杉(Metagequoia Hu etCheng)是我国独存的世界珍贵子遗树种.在距今一亿年前的白垩纪,水杉一类起源于北极圈内,当时气候温暖,最北分布离北极只有8度,到了距今四千万年前的第三纪,这类植物因地球上气候变冷而逐渐南移,广泛分布于北半球的格林兰、冰岛、欧洲、北美、西伯利亚、中国和日本等地,在第四纪,地球上冰川降临,中欧、北美均为整块巨大的冰块所复盖,水杉一类植物为浩荡奔流的冰川所灭绝,当时,我国也有冰川发生,但与欧美不同,不是整块的巨冰,而是局部的山地冰川,所以水杉得以在我国保存.
Metasequoia Hu et Cheng is one of the world’s precious preserved subspecies in our country.In the Cretaceous one hundred million years ago, Metasequoia Hu et Cheng was originated in the Arctic Circle, when the climate was warm, with the northernmost distribution being only 8 degrees from the North Pole, By the Tertiary age 40 million years ago, these plants gradually moved southward as a result of the global warming of the Earth. They are widely distributed in the northern hemispheres of Greenland, Iceland, Europe, North America, Siberia, China and Japan Quaternary, the advent of glaciers on Earth, Central Europe, North America are covered by a huge piece of ice, Metasequoia a class of plants for the mighty stream of glaciers extinction, when there are glaciers in our country, but different from Europe and the United States, not the whole Massive ice, but a local mountain glacier, so Metasequoia can be preserved in our country.