Selective stabilization of aliphatic organic carbon by iron oxide.
Selective stabilization of aliphatic organic carbon by iron oxide.
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DOI：
10.1038/srep11214
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发表时间：
2015-06-10
影响因子：
4.6
通讯作者：
Yang Y
中科院分区：
文献类型：
--
作者：
Adhikari D;Yang Y
土壤有机质的稳定对于自然生态系统固碳、减缓温室气体排放具有重要意义。什么因素控制着土壤中有机碳的保存在很大程度上是未知的，这给预测土壤对气候变化的反应蒙上了一层阴影。氧化铁被认为是保存土壤有机碳的重要矿物。然而，铁矿物容易被还原，潜在地释放铁并降低铁结合有机碳的稳定性。有关铁结合的有机碳在氧化还原反应中的稳定性的信息有限。在这里，我们研究了有机物与赤铁矿的吸附作用和赤铁矿结合的有机物的还原释放。分析了还原反应中有机质的组成和形态对其在赤铁矿上的吸附和释放的影响。我们发现，赤铁矿结合的脂肪族碳更耐还原释放，尽管赤铁矿更倾向于吸附更多的芳香碳。还原释放阻力代表了脂肪类土壤有机质与氧化铁缔合稳定的新机制。脂肪碳对芳香碳的选择性稳定作用可以极大地促进广泛观察到的脂肪碳在土壤中的积累，这不能用矿物和有机质之间的吸附作用来解释。
Stabilization of organic matter in soil is important for natural ecosystem to sequestrate carbon and mitigate greenhouse gas emission. It is largely unknown what factors govern the preservation of organic carbon in soil, casting shadow on predicting the response of soil to climate change. Iron oxide was suggested as an important mineral preserving soil organic carbon. However, ferric minerals are subject to reduction, potentially releasing iron and decreasing the stability of iron-bound organic carbon. Information about the stability of iron-bound organic carbon in the redox reaction is limited. Herein, we investigated the sorptive interactions of organic matter with hematite and reductive release of hematite-bound organic matter. Impacts of organic matter composition and conformation on its sorption by hematite and release during the reduction reaction were analyzed. We found that hematite-bound aliphatic carbon was more resistant to reduction release, although hematite preferred to sorb more aromatic carbon. Resistance to reductive release represents a new mechanism that aliphatic soil organic matter was stabilized by association with iron oxide. Selective stabilization of aliphatic over aromatic carbon can greatly contribute to the widely observed accumulation of aliphatic carbon in soil, which cannot be explained by sorptive interactions between minerals and organic matter.
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影响因子：
3
作者：
Hedges, JI;Keil, RG;Benner, R
通讯作者：
Benner, R
影响因子：
4.2
作者：
Kaiser, K;Guggenberger, G
通讯作者：
Guggenberger, G
影响因子：
3
作者：
Kaiser, K;Guggenberger, G
通讯作者：
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影响因子：
10.3
作者：
Burgin, Amy J.;Yang, Wendy H.;Silver, Whendee L.
通讯作者：
Silver, Whendee L.
影响因子：
64.8
作者：
Schmidt, Michael W. I.;Torn, Margaret S.;Trumbore, Susan E.
通讯作者：
Trumbore, Susan E.