Submicron structures provide preferential spots for carbon and nitrogen sequestration in soils.
Submicron structures provide preferential spots for carbon and nitrogen sequestration in soils.
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DOI：
10.1038/ncomms3947
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发表时间：
2014
影响因子：
16.6
通讯作者：
Kogel-Knabner, Ingrid
中科院分区：
文献类型：
--
作者：
Vogel, Cordula;Mueller, Carsten W;Hoschen, Carmen;Buegger, Franz;Heister, Katja;Schulz, Stefanie;Schloter, Michael;Kogel-Knabner, Ingrid
土壤中粘土大小的颗粒对碳和氮的固定是公认的，粘粒含量或矿物表面积被用来估计土壤的固定潜力。在这里，通过培养筛子(<；2 mm)表层土壤和标记的凋落物，我们发现只有一些粘土大小的表面结合了有机物(OM)。令人惊讶的是，19%的可见矿物区显示出OM附着。有机质优先与表面粗糙的有机矿团簇共生。通过结合纳米级二次离子质谱仪和同位素示踪，我们区分了新标记的OM和先前存在的OM，并表明新的OM优先连接到已经存在的有机矿物簇上。这些结果提供了证据，表明只有有限比例的粘土大小的表面对OM固存有贡献，这些结果彻底改变了我们对土壤中碳固存的看法和广泛使用的碳饱和度估计。粘土大小的颗粒结合了土壤中的有机质，并固定了土壤中的碳和氮，但有机质覆盖的范围和位置尚不清楚。使用NanoSIMS，Vogel等人。以超高分辨率对土壤进行化学成像，并显示只有表面粗糙的颗粒才能与有机物反应。
The sequestration of carbon and nitrogen by clay-sized particles in soils is well established, and clay content or mineral surface area has been used to estimate the sequestration potential of soils. Here, via incubation of a sieved (<2 mm) topsoil with labelled litter, we find that only some of the clay-sized surfaces bind organic matter (OM). Surprisingly, <19% of the visible mineral areas show an OM attachment. OM is preferentially associated with organo-mineral clusters with rough surfaces. By combining nano-scale secondary ion mass spectrometry and isotopic tracing, we distinguish between new labelled and pre-existing OM and show that new OM is preferentially attached to already present organo-mineral clusters. These results, which provide evidence that only a limited proportion of the clay-sized surfaces contribute to OM sequestration, revolutionize our view of carbon sequestration in soils and the widely used carbon saturation estimates. Clay-sized particles bind organic matter and sequester carbon and nitrogen in soils, yet extent and localization of organic matter coverage remain unclear. Using NanoSIMS, Vogel et al. chemically image soils at ultra-high resolution and show that only particles with rough surfaces react with organic matter.