Proceeded from the relationship between geochemical environment and mankind existence, and based on the data of regional stream sediment survey, the geochemical environment map is drown up.

本文从地球化学环境与人类生存关系出发，依据区域化探水系沉积物资料编制环境地球化学图。

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But only 40 years ago it seemed impossible that mankind would ever map the billions of letters in its own DNA.

但就在40年前，人类描绘自身dna的亿万个字母这样的事看上去还不可能。

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