【摘要】 镁元素是常量元素之一,也是生物维持生命活动的重要物质之一。含镁矿物的风化产物经河流输送到达海洋,并在此过程参与生态系统的物质循环,最终通过碳酸盐沉淀重新成岩,这一过程与全球的碳循环密切相关。近年来,随着非传统金属同位素体系的不断完善,以及MC-ICP-MS(多接收器电感耦合等离子质谱仪)的使用,镁同位素的测试精度与便利程度都有提升,镁同位素因为其广泛参与化学风化过程以及与生命活动密切相关,从而成为示踪表生环境中物质来源与各类生物地球化学过程的有效工具。因此,研究镁同位素在各类生态系统中的组成特征与分馏机理,可以帮助我们了解生态系统内发生的各类地球化学过程,进而探寻全球物质循环与气候变化规律。本文系统阐述了森林生态系统中各组分镁同位素的组成和分馏的影响因素,提出了目前森林生态系统研究存在的问题,并基于现有研究成果对未来森林生态系统中镁同位素的研究方向进行了探讨。更多还原

【Abstract】 Magnesium,one of the major elements,is important substance for life-sustaining activities. The weathering products of magnesium-containing minerals are transported by river to the ocean,in which magnesium participates in ecosystem material cycling,and finally undergo re-diagenesis as carbonate precipitation. This process is closely related to global carbon cycle.Recently,with the improvement of non-traditional metal isotope systems and the use of MC-ICPMS( multi-receiver inductively coupled plasma mass spectrometer),the accuracy and convenience of magnesium isotope analysis have been substantially improved. Magnesium plays an important role in the chemical weathering process and life activities and becomes an effective tool for tracing the material sources and various geochemical processes in the surficial environment.Therefore,studying the characteristics and fractionation mechanism of magnesium isotope can help us understand different geochemical processes occurring in the surficial ecosystem and explore the global element cycle and climate changes. This review systematically expounds the magnesium isotopes composition of various components and the controlling factors of fractionation in forest ecosystems. We also summarized the problems existing in the current forest ecosystem research and proposed the future research directions of magnesium isotope in forest ecosystems.更多还原