Our understanding of the controls regulating the rate of litter decomposition is important for improving confidence in the parameterization of carbon cycle–climate feedbacks. Traditional conceptual models rely primarily on climate and lignin/N ratios as the main regulators of decomposition. Here we studied the effects of manganese (Mn) addition on long-term decomposition across 18 substrates in a laboratory incubation. Mn addition remarkably promoted later stage of decomposition, resulting into a smaller fraction of slowly decomposing litter. This dynamic is closely associated with the changes of activities of manganese peroxidase, an important enzyme with greater capacity for lignin degradation. Our findings suggest the necessity of incorporating the interaction of Mn and decomposition into biogeochemical models.

我们对调节凋落物分解速率的控制的理解对于提高对碳循环-气候反馈参数化的信心很重要。传统的概念模型主要依赖气候和木质素/N 比率作为分解的主要调节因素。在这里，我们研究了锰 (Mn) 添加对实验室培养中 18 种底物的长期分解的影响。Mn 的添加显着促进了分解的后期，导致缓慢分解的垃圾中的一小部分。这种动态与锰过氧化物酶活性的变化密切相关，锰过氧化物酶是一种具有更大木质素降解能力的重要酶。我们的研究结果表明有必要将锰和分解的相互作用纳入生物地球化学模型。