No in‐depth studies covering litter decomposition were previously conducted on afforested postmining sites despite the importance of litter decomposition on soil formation, especially in degraded areas. We aimed to compare leaf litter decomposition rates of 14 tree species growing in mixed stands on a postmining spoil heap, and to compare their decay rates with those obtained in pure stands of tree species that are very often planted in postmining areas. The study was conducted on the Bełchatów Lignite Mine spoil heap, central Poland. We studied litter decomposition rates over 5 years using the litterbag method. Leaf litter decomposition rates (k constants; yr⁻¹) after 5 years of the experiment were arranged from highest to lowest as follows: Prunus serotina (1.04), Alnus glutinosa (0.86), Fraxinus excelsior (0.81), Ulmus laevis (0.73), Acer pseudoplatanus (0.68), Populus tremula (0.63), Populus × canadensis (0.59), Betula pendula (0.54), Populus nigra ‘Italica’ (0.38), Quercus rubra (0.36), Pinus sylvestris (0.34), Robinia pseudoacacia (0.34), Fagus sylvatica (0.25), and Quercus robur (0.22). Decomposition rates increased with Mg, Ca, and summed Mg + Ca + P + K contents in freshly fallen leaves (%). All species‐specific decomposition rates were higher in mixed than in Scots pine stands. Half of them were also higher than in pure stands of other tree species. Our results indicate that tree species composition could significantly affect the physiochemical properties of upper soil horizons on reclaimed areas. Based on these findings, we recommend planting high share of not only A. pseudoplatanus, A. glutinosa, and U. laevis but also F. sylvatica and Q. robur in stands on postmining spoil heaps, because mixed stands can accelerate soil development more than pure stands.

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混合树架在采矿后恢复上层土壤层中的优势：五年凋落物分解实验

尽管凋落物分解对土壤形成（特别是在退化地区）具有重要意义，但以前没有在造林后的采掘场进行深入研究，包括凋落物分解。我们的目的是比较采后弃土堆上混合林中生长的14种树种的凋落物分解率，并将其与采后地区经常种植的纯树种的枯萎率进行比较。这项研究是在波兰中部Bełchatów褐煤矿渣堆上进行的。我们使用垃圾袋方法研究了5年内的垃圾分解率。实验5年后的凋落物分解速率（k常数； yr ^-1）从最高到最低排列如下：樱桃李（1.04），桤木（0.86），欧洲白蜡树（0.81），榆蟾（0.73），宏基pseudoplatanus（0.68），欧洲山杨（0.63），杨×飞蓬（0.59），垂枝桦（0.54），黑杨' Italica'（0.38），杨栎（0.36），樟子松（0.34），刺槐（0.34），樟子松（Fabus sylvatica）（0.25）和栎（0.22）。分解速率随Mg，Ca的增加而增加，并且新鲜下落的叶子中Mg + Ca + P + K的总含量（％）。混交中所有物种特定的分解率均高于苏格兰松林。其中一半还高于其他树种的纯林。我们的结果表明，树种组成可能会严重影响开垦区上层土壤层的理化特性。基于这些发现，我们建议不仅种植高份额A. pseudoplatanus，A.黄和U.蟾也F. sylvatica和Q。 罗伯 在采后弃土堆上的林分中，因为混交林比纯林分更能促进土壤发育。