Organic materials input is remarkably essential for soil aggregates formation and breakdown processes. Which characteristics of organic materials control soil aggregate turnover is still largely unknown. Eleven organic materials were characterized in terms of nutrient stoichiometry, biochemical features and carbon (C) functional groups. The effects of organic matter characteristics on soil aggregate turnover were investigated by using rare earth oxides (REOs) as tracers. REOs concentrations in four aggregate fractions were measured on 0, 14, 28, and 56 d of incubation to calculate the aggregates transformation paths and turnover time. Our results exhibited that aggregate turnover time was reduced considerably with the addition of organic materials in order of easily decomposed residues (ED) < moderately decomposed residues (MD) < slowly decomposed manures (SD) but increased within aggregate fractions in sequence of silt and clay fractions < macroaggregates < microaggregates, such effects attenuated over time (P < 0.05). Nutrient stoichiometry had no impacts on relative changes and turnover time of aggregates. Soluble sugars increased the formation of large macroaggregates at early stage of incubation, but laid no impacts on aggregate turnover time. Lignin reduced soil aggregates formation but increased aggregate turnover time in the first four weeks. C functional groups showed short-term effects on relative changes of aggregates while these characteristics did not explain aggregate turnover time except aromatic carbon. Under ED treatments, the relative formation of 0.053–0.25 mm aggregates increased with the accelerating breakdown of macroaggregates, suggesting the formation of stable microaggregates in the mid-to-late incubation time. With MD and SD application, the relative formation was increased with the decrease of aggregate breakdown over time. We proposed the pathways of soil aggregates turnover, in which the stable microaggregates were released with the breakdown of stable macroaggregates in ED treatments, while such transformation was not observed in MD or SD treatments during the incubation time. Our results demonstrate that aggregate turnover depends on the initial characteristics of incorporated organic matters defined by biochemical features and C functional groups.

有机材料输入对于土壤团聚体的形成和分解过程非常重要。有机物质的哪些特性控制着土壤团聚体的周转仍然很大程度上是未知的。在营养化学计量、生化特征和碳 (C) 官能团方面对 11 种有机材料进行了表征。以稀土氧化物（REO）为示踪剂，研究了有机质特性对土壤团聚体周转的影响。在孵化 0、14、28 和 56 d 时测量四种聚合级分中的 REO 浓度，以计算聚合转化路径和周转时间。我们的结果表明，随着有机材料的添加，总周转时间显着减少，顺序为易分解残留物 (ED) < 中度分解残留物 (MD) <磷 < 0.05)。营养化学计量对聚集体的相对变化和周转时间没有影响。可溶性糖在孵化早期增加了大聚集体的形成，但对聚集体周转时间没有影响。木质素减少了土壤团聚体的形成，但增加了前 4 周的团聚体周转时间。C 官能团对聚集体的相对变化表现出短期影响，而这些特征并不能解释除芳香碳外的聚集体周转时间。在 ED 处理下，0.053-0.25 mm 聚集体的相对形成随着大聚集体的加速分解而增加，表明在中后期孵化时间形成了稳定的微聚集体。随着 MD 和 SD 的应用，随着时间的推移，随着骨料分解的减少，相对形成增加。我们提出了土壤团聚体周转的途径，其中稳定的微团聚体在 ED 处理中随着稳定的大团聚体的分解而释放，而在孵育期间在 MD 或 SD 处理中没有观察到这种转变。我们的结果表明，总营业额取决于由生化特征和 C 官能团定义的有机物的初始特征。