PDF(Pubmed)
Abstract：
Nitrogen is a vital element for life on Earth. Its cycling between the surface (atmosphere + crust) and the mantle has a profound influence on the atmosphere and climate. However, our understanding of the origin and evolution of Earth\'s nitrogen is still incomplete. This review presents an overview of the current understanding of Earth\'s nitrogen budget and the isotope composition of different reservoirs, laboratory constraints on deep nitrogen geochemistry, and our understanding of the origin of Earth\'s nitrogen and the deep nitrogen cycle through plate subduction and volcanism. The Earth may have acquired its nitrogen heterogeneously during the main accretion phase, initially from reduced, enstatite-chondrite-like impactors, and subsequently from increasingly oxidized impactors and minimal CI-chondrite-like materials. Like Earth\'s surface, the mantle and core are also significant nitrogen reservoirs. The nitrogen abundance and isotope composition of these three reservoirs may have been fundamentally established during the main accretion phase and have been insignificantly modified afterwards by the deep nitrogen cycle, although there is a net nitrogen ingassing into Earth\'s mantle in modern subduction zones. However, it is estimated that the early atmosphere of Earth may have contained ∼1.4 times the present-day atmospheric nitrogen (PAN), with ∼0.4 PAN being sequestered into the crust via biotic nitrogen fixation. In order to gain a better understanding of the origin and evolution of Earth\'s nitrogen, directions for future research are suggested.
摘要：
氮是地球上生命的重要元素。它在地表（大气地壳）和地幔之间的循环对大气和气候具有深远的影响。然而,我们对地球氮的起源和演化的理解仍然不完整。这篇综述概述了当前对地球氮收支和不同储层同位素组成的理解，深层氮地球化学的实验室限制，以及我们通过板块俯冲和火山活动对地球氮的起源和深层氮循环的理解。地球可能在主要吸积阶段异质地获得了氮，最初从减少，反辉石-球粒陨石样冲击器，随后来自日益氧化的撞击器和极小CI-球粒陨石样材料。像地球表面,地幔和岩心也是重要的氮储层。这三个储层的氮丰度和同位素组成可能在主要吸积阶段已经基本建立，并且在之后被深层氮循环所改变。尽管在现代俯冲带中存在净氮进入地球地幔的现象。然而,据估计，地球早期大气可能含有1.4倍于当今大气氮(PAN)，0.4PAN通过生物固氮被隔离到地壳中。为了更好地了解地球氮的起源和演化,提出了未来研究的方向。
