Sources and reaction pathways of soluble Fe from the Western Antarctic Peninsula to the Southern Ocean

这项研究的目的是揭示在南大洋靠近海洋岛屿的区域中，可溶性铁的高供应的来源和机制，该区域具有促进浮游生物生长的共同作用。这项研究的重点将放在西南极半岛的乔治王岛(KGI)。冰川喷流物质、陆架沉积物和孔隙水中的铁同位素、水柱剖面和全成岩无机地球化学剖面将用于提取铁的来源和供应途径。鉴于全球变暖导致冰川在KGI上的快速消退和冰川侵蚀物质的喷出增强，将探讨三种可能的反应途径：1)高生产力推动的铁的早期成岩循环和沉积物外扩散；2)表层沉积物中固体活性铁相(包括成岩铁氧化物)的积累和再悬浮；3)冰川喷出物中活性铁矿物和富铁硅酸盐的直接溶解。为了研究铁供应途径的动态及其与气候变化的潜在关系，将对高溢出区(Potter Cove，Maxwell Bay)和低溢出区(金钟湾)进行比较。

The objective of this study is to reveal sources and mechanisms responsible for high supply of soluble Fe in regions close to ocean islands in the otherwise HPLC Southern Ocean with the common effect of stimulating plankton growth. The focus of this study will be on King George Island (KGI), Western Antarctic Peninsula. Fe isotopes from glacial outwash material, shelf sediments and porewaters, and transects of water column profiles together with full diagenetic inorganic geochemical profiling will be used to fingerprint Fe sources and supply pathways. In the light of rapid glacier retreat on KGI due to global warming and enhanced outwash of glacially eroded material, three possible reaction pathways will be investigated: 1) early diagenetic recycling of Fe and diffusion out of sediments fuelled by high productivity; 2) accumulation and resuspension of solid reactive Fe phases (including diagenetic Fe-oxyhydroxides) in surface sediments; 3) direct dissolution of reactive Fe minerals and Fe-rich silicates from glacial outwash. In order to address the dynamics of Fe supply pathways and a potential relationship to climate change, high outwash regions (Potter Cove, Maxwell Bay) will be compared with a low outwash region (Admiralty Bay).