权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Adsorption of humic acid to interlamellar surfaces of montmorillonite

腐殖酸在蒙脱石层间表面的吸附

基本信息

批准号：
NE/H010955/1
负责人：
William Dubbin
金额：
$ 9.03万
依托单位：
Natural History Museum
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2010
资助国家：
英国
起止时间：
2010 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FH010955%2F1
关键词：
Adsorption humic acid interlamellar surfaces

项目摘要

The world's soils are the largest repository of terrestrial organic carbon, nearly 3 times larger than the terrestrial biotic C pool, and more than twice the size of the atmospheric C pool. Despite the magnitude of the soil organic carbon (SOC) reservoir, there is considerable potential for further SOC additions, especially in managed ecosystems, with rates of SOC sequestration estimated to be as high as 1.2 Gigatons per year. These SOC additions have been proposed as a means to offset greenhouse gas emissions, thereby helping to achieve targets established within the Kyoto Protocol. Among the various fractions to which SOC may be sequestered, only the passive pool, with mean residence times in excess of 1,000 years, has sufficient stability to serve as a suitable long-term store of organic C. Placement of organic C in this refractory pool therefore remains the aim of all comprehensive C sequestration strategies. Among the most recalcitrant organic molecules are the humic substances, such as humic acid and fulvic acid. These materials are particularly resistant to degradation when they are strongly adsorbed to mineral surfaces. Thus, mineral-complexed humic materials are an important and desirable component of the stable SOC reservoir. The aim of this investigation is to determine how humic acid becomes adsorbed to the internal surfaces of montmorillonite, a common soil mineral. We will test the hypothesis that a certain group of natural organic molecules, possessing long saturated hydrocarbon chains and bound to montmorillonite edges, serve as attachment points for the humic acid, thus positioning this organic molecule near the gallery entrance and so facilitating interlamellar adsorption. Our data will reveal the mechanisms through which humic materials become intercalated by expanding layer silicates, contributing to the stable SOC pool. This research will also inform global soil C management strategies, guiding C sequestration efforts to those soils in which long-term organic C storage is most favoured.

土壤是地球上最大的陆地有机碳库，比陆地生物碳库大近3倍，是大气碳库的两倍多。尽管土壤有机碳（SOC）库的规模，有相当大的潜力，进一步增加SOC，特别是在管理的生态系统中，SOC封存率估计高达每年1.2千兆吨。这些SOC的增加被提议作为抵消温室气体排放的一种手段，从而有助于实现《京都议定书》中确立的目标。在有机碳可能被隔离的各个部分中，只有平均停留时间超过1,000年的被动库具有足够的稳定性，可以作为有机碳的适当长期储存。因此，将有机碳放置在这个耐火池中仍然是所有综合碳封存策略的目标。在最难降解的有机分子中，有腐殖酸，如腐殖酸和富里酸。当这些材料被强烈吸附到矿物表面时，它们特别抗降解。因此，矿物复合腐殖物质是稳定的SOC储层的重要和理想的组成部分。本研究的目的是确定腐殖酸是如何被吸附到蒙脱石（一种常见的土壤矿物）的内表面的，我们将测试这样一种假设：一组天然有机分子，具有长的饱和烃链，并与蒙脱石边缘结合，作为腐殖酸的附着点，从而将这种有机分子定位在廊道入口附近，从而促进层间吸附。我们的数据将揭示腐殖物质通过膨胀层硅酸盐插入的机制，有助于稳定的SOC池。这项研究还将为全球土壤碳管理战略提供信息，指导碳固存工作，以长期有机碳储存最受欢迎的土壤。