The invasion of Amynthas species complex of earthworms from Asia into North American hardwood forests poses a novel threat to these ecosystems. These species can competitively exclude previously-established earthworms, have novel effects on microbial communities, and influence the structural and chemical composition of soils differently than other earthworm species. However, because prior research has found that earthworm species is an important factor for microbial community composition, Amynthas species may also uniquely affect soil microbial community composition. To address this, we took earthworm and soil samples from 0.5-m quadrats along an active invasion front of Amynthas agrestis and A. tokioensis at the University of Wisconsin-Madison Arboretum. We tested all soil samples for basal metabolic rates, total carbon, and total nitrogen. We also extracted microbial DNA from cast samples, dissected worm guts, and soil samples, and we used high-throughput DNA sequencing to characterize Amynthas species-specific differences in bacterial and fungal community composition. We found that plots that had been occupied by Amynthas for longer than a year had higher total nitrogen, lower C/N, and different communities of soil bacteria and fungi when compared to newly-invaded plots. We also found that Amynthas had species-specific differences in bacterial communities adhered to worm guts and in worm casts. These results suggest that Amynthas species introduce novel assemblages of bacteria and fungi through their casts, and these differences are associated with the species-specific community composition of earthworm guts. These results also suggest that Amynthas species are likely affecting the soil microbial community during invasion.

来自亚洲的worm的Amynthas物种复合体向北美硬木森林的入侵对这些生态系统构成了新的威胁。这些物种可以竞争性地排除先前建立的earth，对微生物群落产生新的影响，并与其他earth物种不同地影响土壤的结构和化学组成。但是，由于先前的研究已经发现worm物种是影响微生物群落组成的重要因素，因此Amynthas物种也可能独特地影响土壤微生物群落组成。为了解决这个问题，我们从Amynthas agrestis和A. tokioensis的活跃入侵前沿采集了0.5米长方体的earth和土壤样本威斯康星大学麦迪逊分校的植物园。我们测试了所有土壤样品的基础代谢率，总碳和总氮。我们还从粪便样本，解剖的肠虫和土壤样本中提取了微生物DNA，并使用高通量DNA测序来表征Amynthas细菌和真菌群落组成中物种特异性的差异。我们发现，与新入侵的土地相比，被Amynthas占领超过一年的土地具有较高的总氮，较低的C / N以及不同的土壤细菌和真菌群落。我们还发现Amynthas在附着于蠕虫肠道和蠕虫铸型的细菌群落中具有物种特异性差异。这些结果表明Amynthas物种通过它们的表皮引入细菌和真菌的新颖组合，这些差异与earth肠道的特定物种群落组成有关。这些结果还表明，Amynthas物种可能在入侵过程中影响土壤微生物群落。