东南极中山站-Dome A断面雪冰中铁的时空变化及其影响机制研究

大气沉降铁作为南大洋中生物可利用铁的一个重要来源，能够通过影响浮游植物对碳的固定，进而影响全球碳循环和气候变化。南极雪冰中记录的大气沉降铁，可以用来估算南大洋大气沉降铁的通量，近年来逐渐成为研究热点。然而，迄今对南极雪冰中铁的来源、时空变化特征及影响机制的研究还相当有限。因此，本项目依托中国南极考察，拟开展东南极中山站-Dome A断面雪冰中大气沉降铁的研究，通过分析雪冰中铁的浓度及稳定同位素特征，结合矿物组成等地球化学参数，分析东南极雪冰中大气沉降铁时空分布特征及其影响机制；探讨人类活动对雪冰中大气沉降铁的影响及贡献。本研究将会有效加强对南极及其周边地区大气沉降铁传输规律的认知水平，为南大洋铁库存的估算提供有效数据。

Atmospheric iron has been considered as a significant source of potentially bioavailable Fe to the Southern Ocean (SO), which will influence the carbon fixation by phytoplankton, thus the global carbon cycle and eventually the global climates. The records of atmospheric iron in Antarctic snow and ice, which can be used to evaluate the atmospheric iron flux to the SO, have gradually become the hotspot in recent years. However, the research on the source, spatiotemporal variation characteristics and influencing mechanism of iron in Antarctic snow and ice is still very less. Here we report the atmospheric iron in snow and ice along the transect from Zhongshan Station to Dome A in East Antarctica in the frame of Chinese National Antarctica Research Expedition (CHINARE). Based on the iron concentration and stable isotope characteristics in snow and ice, combined with mineral composition and other geochemical parameters, the spatial and temporal distribution characteristics of atmospheric iron in snow and ice in the East Antarctica and its influencing mechanism will be analyzed. Besides, the influence and contribution of human activities on atmospheric iron in snow and ice in the East Antarctica will be also paid close attention. This project would significantly promote our understanding of the atmospheric iron in Antarctica and its surrounding areas, and provide reliable data for the estimation of iron budget in the SO.