Institute of Environment and Ecology, Academy of Environmental Health and Ecological Security & School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China.
Plant Biol (Stuttg). 2018 Jan;20(1):151-159. doi: 10.1111/plb.12646. Epub 2017 Nov 21.
Soil fungal communities play an important role in the successful invasion of non-native species. It is common for two or more invasive plant species to co-occur in invaded ecosystems. This study aimed to determine the effects of co-invasion of two invasive species (Erigeron annuus and Solidago canadensis) with different cover classes on soil fungal communities using high-throughput sequencing. Invasion of E. annuus and/or S. canadensis had positive effects on the sequence number, operational taxonomic unit (OTU) richness, Shannon diversity, abundance-based cover estimator (ACE index) and Chao1 index of soil fungal communities, but negative effects on the Simpson index. Thus, invasion of E. annuus and/or S. canadensis could increase diversity and richness of soil fungal communities but decrease dominance of some members of these communities, in part to facilitate plant further invasion, because high soil microbial diversity could increase soil functions and plant nutrient acquisition. Some soil fungal species grow well, whereas others tend to extinction after non-native plant invasion with increasing invasion degree and presumably time. The sequence number, OTU richness, Shannon diversity, ACE index and Chao1 index of soil fungal communities were higher under co-invasion of E. annuus and S. canadensis than under independent invasion of either individual species. The co-invasion of the two invasive species had a positive synergistic effect on diversity and abundance of soil fungal communities, partly to build a soil microenvironment to enhance competitiveness of the invaders. The changed diversity and community under co-invasion could modify resource availability and niche differentiation within the soil fungal communities, mediated by differences in leaf litter quality and quantity, which can support different fungal/microbial species in the soil.
土壤真菌群落对于非本地物种的成功入侵起着重要作用。在入侵生态系统中，两种或多种入侵植物物种共同出现是很常见的。本研究旨在通过高通量测序确定两种入侵物种（豚草和加拿大一枝黄花）不同覆盖度的共同入侵对土壤真菌群落的影响。豚草和/或一枝黄花的入侵对土壤真菌群落的序列数、操作分类单元（OTU）丰富度、香农多样性、基于丰度的覆盖估计（ACE 指数）和 Chao1 指数有积极影响，但对辛普森指数有负面影响。因此，豚草和/或一枝黄花的入侵可以增加土壤真菌群落的多样性和丰富度，但降低这些群落某些成员的优势度，部分原因是促进植物进一步入侵，因为较高的土壤微生物多样性可以增加土壤功能和植物养分获取。一些土壤真菌物种生长良好，而另一些则在非本地植物入侵后随着入侵程度和时间的增加而趋于灭绝。与单一物种的独立入侵相比，豚草和一枝黄花共同入侵时，土壤真菌群落的序列数、OTU 丰富度、香农多样性、ACE 指数和 Chao1 指数更高。两种入侵物种的共同入侵对土壤真菌群落的多样性和丰度有积极的协同作用，部分原因是构建了一个土壤微环境，增强了入侵物种的竞争力。共同入侵引起的多样性和群落变化可以通过凋落物质量和数量的差异来改变土壤真菌群落内部的资源可利用性和生态位分化，从而支持土壤中不同的真菌/微生物物种。
