Approximately 90% of all annual net primary productivity in temperate deciduous forests ends up entering the detritus food web as leaf litter. Due to chemical and physical differences from native litter, inputs from invasive species may impact the litter-dwelling community and ecosystem processes. We compared leaf-litter nutritional quality and decomposition rates from two invasive shrubs, Lonicera maackii and Rhamnus davurica, and the invasive tree Ailanthus altissima to litter from native oak-hickory forest in the Shenandoah Valley of Virginia, USA. We sampled litter from both invaded and uninvaded habitats and conducted litter colonization experiments to test for effects on microflora and the litter-dwelling arthropod communities. Litter from all three invasive species decomposed more rapidly than native litter, with native habitats averaging two to nearly five times as much litter by June. Invasive litter had higher nitrogen concentration and lower C:N ratios than native litter. Invasive litter supported greater growth of bacteria and fungi. Higher numbers of arthropods colonized invasive litter than native litter, but litter arthropod numbers on the forest floor of invaded habitats dropped in the early summer as litter decomposed. Litter had no effect on arthropod richness. Over short time scales, our results indicate that these invasive species represent beneficial, novel resources for the litter-dwelling community. However, the short-lived nature of this resource resulted in a crash in the abundance of the litter-dwelling organisms once the litter decomposed. As a whole, native habitat seems to support a larger, more stable litter-dwelling community over the course of a growing season.

中文翻译：

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外来树木和灌木的入侵改变了凋落物的微生物区系和节肢动物群落。

在温带落叶林中，每年约90％的净初级生产力最终以落叶的形式进入碎屑食物网。由于天然垃圾的化学和物理差异，外来入侵物种的投入可能会影响垃圾栖息社区和生态系统过程。我们比较了两种入侵灌木（忍冬，忍冬鼠李和鼠李木）以及入侵树臭椿（Ailanthus altissima）与来自美国弗吉尼亚州谢南多厄山谷天然橡树山核桃林的凋落物的凋落物营养质量和分解率。我们从入侵和未入侵的生境取样垃圾，并进行了垃圾定殖实验，以测试其对微生物区系和栖居节肢动物群落的影响。所有三种入侵物种的凋落物的分解速度都比天然凋落物快，到6月，本地栖息地的平均产仔数是原来的2到5倍。外来垃圾比自然垃圾具有更高的氮浓度和更低的C：N比。侵入性垫料支持细菌和真菌的更大生长。侵入性垃圾中的节肢动物数量要高于原生垃圾，但随着垃圾的分解，在入侵栖息地森林地上的节肢动物节肢动物数量在初夏下降。垃圾对节肢动物的丰富度没有影响。在短时间范围内，我们的结果表明，这些入侵物种代表了乱扔垃圾的居民社区的有益新资源。但是，这种资源的短暂寿命导致一旦分解垃圾，大量居住在垃圾中的生物崩溃。总体而言，原生栖息地似乎支持着更大，