Strong relationships exist between litter chemistry traits and rates of litter decomposition. However, leaf traits are more commonly found in online trait databases than litter traits and fewer studies have examined how well leaf traits predict litter decomposition rates. Furthermore, while bulk leaf nitrogen (N) content is known to regulate litter decomposition, few studies have explored the importance of N biochemistry fractions, such as protein and amino acid concentration. Here, we decomposed green leaves and naturally senesced leaf litter of nine species representing a wide range of leaf functional traits. We evaluated the ability of traits associated with leaf and litter physiology, N biochemistry and carbon quality to predict litter decomposition. The objectives of this study were to determine if 1) N fractions explain variation in decomposition that is not explained by bulk N parameters alone and 2) green leaf traits, as opposed to litter traits, can accurately determine rates of litter decomposition. We found N biochemistry traits to have similar predictive power to that of bulk N. We also found that leaf N biochemistry traits correlated strongly with each other and aligned on a single axis of variation resembling that of the ‘leaf economic spectrum.’ We noted that green leaf traits associated with this axis, including bulk N, N fractions, leaf mass per area and lignin, were better predictors of decomposition than litter traits and concluded that leaf trait databases may be used to accurately predict litter decomposition. Future decomposition studies should consider fitting the more flexible Weibull distribution model to litter cohorts, as this model is much less rigid than the classic exponential decay model traditionally used in decomposition studies.

中文翻译：

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叶性状可用于预测凋落物分解的速率

凋落物化学特性与凋落物分解速率之间存在密切关系。但是，相比于凋落物性状，在线性状数据库中更常见叶性状，并且很少有研究检查叶性状如何预测凋落物分解率。此外，虽然已知大量叶子中的氮（N）可以调节凋落物的分解，但很少有研究探索N生化部分（如蛋白质和氨基酸浓度）的重要性。在这里，我们分解了九种植物的绿叶和自然衰老的凋落物，代表了广泛的叶片功能性状。我们评估了与叶片和凋落物生理，氮生化和碳质量相关的性状预测凋落物分解的能力。这项研究的目的是确定1）N分数是否能解释分解的变化，而这不能单独用大量的N参数来解释； 2）绿叶性状（与凋落物性状相反）能否准确地确定凋落物的分解率。我们发现N的生物化学性状具有与散装N相似的预测能力。我们还发现，叶N的生物化学性状彼此之间具有很强的相关性，并在类似于“叶经济谱”的单个变异轴上对齐。我们注意到与该轴相关的绿叶性状（包括大量N，N分数，每单位面积的叶质量和木质素）比凋落物性状更好地预测了分解，并得出结论，叶性状数据库可用于准确预测凋落物的分解。