中文摘要：

极端微生物是地球生物圈的重要组成部分。极端微生物的地球化学定位在微生物学与地球化学以及一些相关学科的交叉点上，最近10年已经发展成为地质生物学研究的热门领域。对极端微生物的研究不仅有助于回答生命起源、生命极限、生命本质甚至其他生命形式等生命科学问题，而且其生物地球化学作用在地球系统科学研究中具有重大科学研究价值，对揭示生物圈与地圈协同演化的奥秘、认识生命与环境相互作用规律及地球的化学演化提供重要证据。总结了嗜热菌、嗜冷菌、嗜酸菌、嗜碱菌、嗜压菌、嗜盐菌以及抗辐射菌的主要类群，论述了极端微生物适应环境的机制，探讨了极端微生物的生物地球化学意义。作者预测未来将会在生物标志化合物研究、同位素地球化学分析和分子生物学综合研究的基础上协同推进极端微生物地球化学学科的发展。

英文摘要：

Extremophiles are an important component of Earth＇s biosphere and constitute a valuable biological resource. The biogeochemistry of extremophiles, an inter-and multidisciplinary subject stemming from microbiology and geochemistry, has in the last decade become the focus of geobiological research. Understanding ex tremophiles not only helps to shed light on important scientific questions, but also has profound impact on the study of earth system science. A breakthrough in extremophile studies may be able to unlock a number of mysteries such as the origin of life, the tolerance of life to environmental changes, and even the possibility for the existence of extraterrestrial life. From the Earth system point of view, knowledge in extremophiles can provide important insights into the pathway of biosphere-lithosphere co-evolution as well as the chemical evolution of the Earth. This paper summarizes the major groups of the known thermophiles （psychophiles, acidophiles, alkaliphiles, barophiles, halophiles and anti-radiate microbes）, reviews the mechanisms of extremophiles adapting to environmental conditions, and discusses the biogeochemical significance of extremophiles. The authors anticipate that future advance in biomarker study, isotope geochemistry, and molecular biology will facilitate and improve our knowledge basis in the biogeochemistry of extremophiles.