Decomposition of leaf litter is influenced by litter quality as determined by plant genotype and environment, as well as climate and soil properties. We studied these drivers of decomposition in communities of Salix varieties, hypothesizing that decomposition rates would increase under warmer climate, in more diverse communities, and with increasing litter quality of the individual varieties. Litter from four Salix varieties was incubated in three field trials across a latitudinal gradient from Central to Northern Europe. Litter and stand properties were measured and used as predictors of decomposition. No significant site differences in remaining mass or nitrogen were found. Instead, effects of initial leaf litter quality on decomposition were stronger than climatic effects. Litter quality of individual varieties strongly affected decomposition, while increasing litter diversity did not. Decomposition was controlled by variety identity depending on site, indicating that local soil conditions affect litter quality (and thus decomposition) more than macroclimate. In mixed communities, varieties producing fast-decomposing litter enhanced the litter decomposition of other components producing slow-decomposing litter, and vice versa. This implies that site conditions partly determine which varieties affect community-level decomposition and nutrient release.

中文翻译：

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与柳树品种相结合的凋落物质量比林分多样性或气候更能驱动凋落物分解

凋落物的分解受凋落物质量的影响，由植物基因型和环境以及气候和土壤特性决定。我们研究了柳柳品种群落分解的这些驱动因素，假设分解率会在气候变暖、群落更加多样化以及单个品种的凋落物质量提高的情况下增加。来自四个 Salix 品种的垫料在三个田间试验中孵化，横跨从中欧到北欧的纬度梯度。凋落物和林分特性被测量并用作分解的预测因子。未发现剩余质量或氮的显着位置差异。相反，初始凋落物质量对分解的影响强于气候影响。个别品种的凋落物质量强烈影响分解，而增加垃圾多样性却没有。分解受不同地点的品种特性控制，表明当地土壤条件比大气候更能影响凋落物质量（从而分解）。在混合群落中，产生快速分解凋落物的品种增强了产生缓慢分解凋落物的其他成分的凋落物分解，反之亦然。这意味着立地条件在一定程度上决定了哪些品种会影响群落水平的分解和养分释放。产生快速分解垫料的品种增强了产生慢速分解垫料的其他成分的垫料分解，反之亦然。这意味着立地条件在一定程度上决定了哪些品种会影响群落水平的分解和养分释放。产生快速分解垫料的品种增强了产生慢速分解垫料的其他成分的垫料分解，反之亦然。这意味着立地条件在一定程度上决定了哪些品种会影响群落水平的分解和养分释放。