Soil fauna precipitate the convergence of organic matter quality during decomposition
Soil fauna precipitate the convergence of organic matter quality during decomposition
复制标题
土壤动物在分解过程中沉淀有机质质量的收敛
作者：
Joly F
植物枯落物是土壤食物网的主要来源，土壤食物网将枯落物分解并转化为土壤有机质。这种转变的一个中心范例假定，不同的凋落物类型之间的质量差异消失在分解过程中，凋落物类型收敛到类似的物理化学特性。然而，这种模式是有争议的，没有明确的衡量标准。它也主要来自微生物分解研究，而通过将大量的垃圾转化为粪便，以垃圾为食的土壤动物的影响仍然很少记录。我们解决了这一知识差距，通过量化的理化特性之间的变异性落叶的对比质量的6个树种，转化为粪便之前和之后，由6种土壤动物。我们发现，不同的土壤动物转化成粪便的凋落物在很大程度上减少了对比凋落物类型之间的物理和化学特性的变异性。我们还通过分解完整的凋落物和土壤动物粪便并比较分解材料的化学特性，评估了这种动物驱动的收敛对分解过程中进一步微生物驱动的收敛的影响。未摄入的垃圾和土壤动物粪便之间的化学变化收敛在类似的速度。这表明动物和微生物驱动的收敛是加性的，土壤动物在分解过程中促进有机质质量收敛。我们在这里提出了一个新的框架和相关的指标来研究分解过程中有机质质量变异的变化，我们认为这是必不可少的一个更好的理解和模拟凋落物分解和土壤有机质的形成。
Plant litter constitutes the dominant resource to soil food webs, which gradually decompose litter and transform it into soil organic matter. A central paradigm of this transformation posits that differences in quality between distinct litter types disappear during decomposition, as litter types converge towards similar physicochemical characteristics. Yet, this paradigm is debated and not based on clear metrics. It is also largely derived from microbial decomposition studies, while the effect of litter‐feeding soil animals, by transforming large quantities of litter into faeces, remains poorly documented. We addressed this knowledge gap by quantifying the variability in physicochemical characteristics amongst leaf litter of six tree species of contrasting quality, before and after conversion into faeces by six soil animal species. We found that litter conversion into faeces by diverse soil animals largely reduced the variability in physical and chemical characteristics between contrasting litter types. We also evaluated the consequences of this animal‐driven convergence on further microbial‐driven convergence during decomposition, by decomposing intact litter and soil animal faeces and comparing the chemical characteristics of decomposed materials. Chemical variability amongst uningested litter and amongst soil animal faeces converged at similar rates. This indicates that animal‐ and microbial‐driven convergence are additive, and that soil animals precipitate organic matter quality convergence during decomposition. We propose here a new framework and an associated metric to study changes in organic matter quality variability during decomposition, which we argue are essential for an improved understanding and modelling of litter decomposition and soil organic matter formation.
影响因子：
3.4
作者：
Coulis, Mathieu;Fromin, Nathalie;Haettenschwiler, Stephan
通讯作者：
Haettenschwiler, Stephan
影响因子：
3.7
作者：
Ball, Becky A.;Christenson, Lynn M.;Wickings, Kyle G.
通讯作者：
Wickings, Kyle G.