Nanoparticles, Colloids and their relationship to Titanium, Aluminium and Iron solubility in the Open Ocean

本文拟详细研究沉积到海洋的大气尘埃的主要成分Al、Fe和Ti三种主要地壳元素的海洋地球化学。所有3种元素在海水中强烈水解，导致低溶解度和高颗粒反应性，导致在公海海水中的低浓度（Al：0.3 - 90 nM，Fe：50 - 2000 pM，Ti：3- 300 pM）。虽然目前有一个强烈的关注铁的地球化学，有很少的工作进行了铝和更少的Ti。PI最近开发了两种新的伏安形态分析技术的Ti和Al，允许第一次检查的原位形态和反应动力学的Ti和Al在公海海水。拟议的工作是围绕在大西洋和南大洋进行的一系列考察，将测量这些金属的可溶性（x < 10 kDa）、胶体（10 kDa < x < 0.2微米）和颗粒（x >0.2微米）浓度。实验室调查将侧重于这些元素在海水中的溶解度;这对于钛尤其重要，因为没有可靠的海水数据，对于所有3种金属，了解这些金属在深海中的迁移以及通过上涌和扩散向表层沃茨的供应。

We propose here to investigate in detail the marine biogeochemistry of three major crustal elements, Al, Fe and Ti which are major constituents of atmospheric dust deposited to the ocean. All 3 elements are strongly hydrolysed in seawater resulting in low solubilities and high particle reactivity resulting in low concentrations in open ocean seawater (Al: 0.3 - 90 nM, Fe: 50 - 2000 pM, Ti: 3- 300 pM). While presently there is a strong focus on the biogeochemistry of iron, there has been little work performed on Al and even less on Ti. The PI has recently developed two new voltammetric speciation techniques for Ti and Al that allow for the first time an examination of the in situ speciation and reaction kinetics of Ti and Al in open ocean seawater. The proposed work is based around a series of cruises in the Atlantic and Southern Ocean, where soluble (x < 10 kDa), colloidal (10 kDa < x < 0.2 um) and particulate (x >0.2 um) concentrations of these metals will be measured. Laboratory investigations will focus on the solubility of these elements in seawater; this is particularly important with regard to Ti, where no reliable data exist for seawater, and for all the 3 metals in understanding the transport of these metals in the Deep Ocean and supply to surface waters by upwelling and diffusion.