*Article* **Impact of Moso Bamboo (***Phyllostachys edulis***) Expansion into Japanese Cedar Plantations on Soil Fungal and Bacterial Community Compositions**

**Haifu Fang 1, Yuanqiu Liu 1,2, Jian Bai 1, Aixin Li 1, Wenping Deng 1,2, Tianjun Bai 2, Xiaojun Liu 1, Meng Lai 1, Yan Feng 2, Jun Zhang 2, Qin Zou 2, Nansheng Wu 3,\* and Ling Zhang 1,2,\***

	- Correspondence: rensh111@126.com (N.W.); lingzhang09@126.com (L.Z.)

**Simple Summary:** Moso bamboo (*Phyllostachys edulis*) expansion caused substantial changes in the ecosystem process. Changes in plant–soil chemical characteristics and microbial community compositions have not been thoroughly studied. To understand changes in forest ecosystem process and the underlining microbial community compositions, we studied changes in plant–soil chemical characteristics and microbial community compositions. The results showed that moso bamboo expansion into Japanese cedar plantations altered litter C:N and divergently affected soil fungal and bacterial community compositions. Specifically, moso bamboo expansion decreased soil organic carbon, total nitrogen, litter carbon, and the carbon to nitrogen ratio. Moso bamboo expansion also increased soil NH4+-N and pH, while it decreased fungi OTUs at the phyla, class, order, family, and genus levels. The expansion of moso bamboo into Japanese cedar substantially altered soil-fungaland bacterial-community structure, which might have implications for changes in the ecosystem element-cycling process.

**Abstract:** Moso bamboo expansion is common across the world. The expansion of moso bamboo into adjacent forests altered plant and soil characteristics. While the community structure of soil fungi and bacteria plays an important role in maintaining the function of forest ecosystems, changes in microbial community compositions remain unclear, limiting our understanding of ecological process changes following moso bamboo expansion. To explore changes in the community structure of soil fungi and bacteria in Japanese cedar plantations experiencing expansion of moso bamboo, Illumina NovaSeq high-throughput sequencing technology was used to elucidate changes in soil microbial communities as well as alteration in litter and soil chemical characteristics. The results showed that moso bamboo expansion decreased content of soil organic carbon, total nitrogen, litter carbon, and the carbon to nitrogen ratio as well as the number of bacterial operational taxonomic units (OTUs) at the genus level, the α-diversity Simple index, and the abundance of *Acidobacteria*, *Chloroflexi*, and *Gemmatimonadetes*. Moso bamboo expansion also increased soil NH4+-N, pH, while it decreased fungi OTUs at the phyla, class, order, family, and genus level. The expansion of moso bamboo into Japanese cedar substantially altered soil fungal and bacterial community structure, which might have implications for changes in the ecosystem element-cycling process. In the forest ecosystem and expansion managemen<sup>t</sup> of moso bamboo, the types and different expansion stages of moso bamboo should be paid attention to, in the assessment of ecological effects and soil microbial structure.

**Citation:** Fang, H.; Liu, Y.; Bai, J.; Li, A.; Deng, W.; Bai, T.; Liu, X.; Lai, M.; Feng, Y.; Zhang, J.; et al. Impact of Moso Bamboo (*Phyllostachys edulis*) Expansion into Japanese Cedar Plantations on Soil Fungal and Bacterial Community Compositions. *Forests* **2022**, *13*, 1190. https:// doi.org/10.3390/f13081190

**\***

Academic Editors: Fuzhong Wu, Zhenfeng Xu and Wanqin Yang

Received: 19 June 2022 Accepted: 21 July 2022 Published: 27 July 2022

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/).

**Keywords:** litter decomposition; soil organic carbon; microbial community composition; plant invasion ecology
