Response of Soil AMF Diversity to Nitrogen Deposition in a Calamagrostis augustifolia Wetland of Sanjiang Plain, China

摘要

Calamagrostis angustifolia Kom, a perennial plant of the family Gramineae, is the main species of the Sanjiang Wetland, China. Because of global climate change and the impact of human activities, the Sanjiang Plain Wetland has been seriously degraded, which has had a serious impact on stability of the ecosystem in Northeast China. Arbuscular mycorrhizal (AM) symbiosis can play a major role in enhancing stress resistance. In this study, soil diversity, physiochemical properties, and ITS rDNA responses of AM fungi with C. augustifolia under three nitrogen depositions at different loads were investigated. The results showed that both low-and high-level nitrogen deposition reduced the AM fungal diversity. In each of the three types of nitrogen-amended soils, the most predominant phylum was Glomeromycota. The abundance of Glomeromycota decreased with nitrogen deposition. A heatmap tree based on internal transcribed spacers (ITS) rDNA sequences established that different arbuscular mycorrhizal fungal communities respond differently to nitrogen deposition. Based on our results, we posit that changes in nitrogen deposition gradient in this study influenced the soil AM fungal community structure in Sanjiang Plain Wetland, especially those belonging to the phylum Glomeromycota.