<br>有机-有机相互作用主要驱动土壤有机碳累积,Global Change Biology

当前位置： X-MOL 学术 › Glob. Change Biol. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

有机-有机相互作用主要驱动土壤有机碳累积
Global Change Biology ( IF 10.8 ) Pub Date : 2024-01-11 , DOI: 10.1111/gcb.17147
Jie Kang _{1,

2} , Chenchen Qu _{1,

2} , Wenli Chen ₁ , Peng Cai _{1,

2} , Chengrong Chen ₃ , Qiaoyun Huang _{1,

2}

Affiliation

有机-矿物相互作用被认为是数十年至千年时间尺度内土壤有机碳（SOC）稳定的主要机制，土壤碳（C）储存能力通常根据土壤矿物学属性（特别是矿物表面）进行评估可用性。然而，土壤碳封存是否完全受矿物空位控制仍然存在争议，这使得准确预测 SOC 动态变得具有挑战性。在这里，通过在两种对比土壤（即 Mollisol 和 Ultisol）中使用¹³ C 标记的有机材料进行 400 天的培养实验，我们表明，尽管两种土壤中的矿物质表面不饱和，但新掺入的 C 主要粘附在“脏土壤”上。 ”矿物表面涂有天然有机质（OM），证明了有机-有机相互作用在外源碳封存中的关键作用。这种相互作用导致多层碳积累，不受矿物空位的限制，这一过程不同于直接的有机-矿物接触。新 C 对天然 OM 的覆盖率（代表有机-有机相互作用的程度）在 Ultisol 中 (~14.2%) 明显大于 Mollisol (~5.8%)，相当于 Ultisol 中外源 C 的净保留量高 0.2- 1.3 g kg ^-1 ，在 Mollisol 中为 0.1–1.0 g kg ^-1 。此外，有机-有机相互作用主要由富含多糖的微生物坏死物介导。进一步的证据表明，氧化铁可以选择性地保留多糖化合物，从而促进有机相互作用。总体而言，我们的研究结果为被忽视但至关重要的碳积累途径提供了直接的经验证据，挑战了强调矿物空位压倒性作用的流行“碳饱和”概念。据估计，通过有机-有机相互作用，全球软土和腐土每年可能分别封存约 0.1-1.0 和约 0.3-1.7 Pg C，相当于约中和。全球土壤碳排放量的 0.5%–3.0% 或化石燃料燃烧的 5%–30%。

"点击查看英文标题和摘要"

Organo–organic interactions dominantly drive soil organic carbon accrual

Organo–mineral interactions have been regarded as the primary mechanism for the stabilization of soil organic carbon (SOC) over decadal to millennial timescales, and the capacity for soil carbon (C) storage has commonly been assessed based on soil mineralogical attributes, particularly mineral surface availability. However, it remains contentious whether soil C sequestration is exclusively governed by mineral vacancies, making it challenging to accurately predict SOC dynamics. Here, through a 400-day incubation experiment using ¹³C-labeled organic materials in two contrasting soils (i.e., Mollisol and Ultisol), we show that despite the unsaturation of mineral surfaces in both soils, the newly incorporated C predominantly adheres to “dirty” mineral surfaces coated with native organic matter (OM), demonstrating the crucial role of organo–organic interactions in exogenous C sequestration. Such interactions lead to multilayered C accumulation that is not constrained by mineral vacancies, a process distinct from direct organo–mineral contacts. The coverage of native OM by new C, representing the degree of organo–organic interactions, is noticeably larger in Ultisol (~14.2%) than in Mollisol (~5.8%), amounting to the net retention of exogenous C in Ultisol by 0.2–1.3 g kg⁻¹ and in Mollisol by 0.1–1.0 g kg⁻¹. Additionally, organo–organic interactions are primarily mediated by polysaccharide-rich microbial necromass. Further evidence indicates that iron oxides can selectively preserve polysaccharide compounds, thereby promoting the organo–organic interactions. Overall, our findings provide direct empirical evidence for an overlooked but critically important pathway of C accumulation, challenging the prevailing “C saturation” concept that emphasizes the overriding role of mineral vacancies. It is estimated that, through organo–organic interactions, global Mollisols and Ultisols might sequester ~0.1–1.0 and ~0.3–1.7 Pg C per year, respectively, corresponding to the neutralization of ca. 0.5%–3.0% of soil C emissions or 5%–30% of fossil fuel combustion globally.

更新日期：2024-01-14

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南

全部期刊列表>>