Nutrients Availability Shapes Fungal Community Composition and Diversity in the Rare Earth Mine Tailings of Southern Jiangxi, China

Abstract

The present study characterized the nutrients availability of three rare earth tailings deserted in different time stages in Southern Jiangxi of China, and revealed the influence of the soil nutrient properties on fungi composition and diversity by using an internal transcribed spacer (ITS) rRNA sequence approach. Three tailings (RS1, RS2 and RS3) and one reference soil (RS4) were sampled. Results showed that a higher levels of AN and TOC occurred in RS1 and RS4, whereas higher contents of SO^2-₄, TN, NO^-₃-N, NH⁺₄-N and rare earth elements (REEs) existed in RS2 and RS3, suggesting a high environmental heterogeneity in the different tailings. Metagenomic analysis showed that RS1~RS4 harbored 355, 564, 366 and 507 operational taxonomic units (OTUs), respectively. Alpha diversity analysis showed that RS4, a control sample, had the highest Shannon diversity, whereas RS3, a newly formed tailings, exhibited the lowest Chao1 richness.

Among the monitored environmental variables, AN and SO^2-₄ were the most important factors affecting the overall fungal community composition and the relative abundances of specific lineages. Additionally, genus Penicillium prevailed in RS1and RS4 while genus Aspergillus dominated in RS2 and RS3, indicating that the nitrification maybe conduct by different fungal genus in different tailings. Together, these results suggest that lower fungal community composition and diversity as well as the alteration in fungi-dominated heterotrophic nitrification may be due to the deteriorative nutrient in rare earth tailings, especially increasing level of sulfate and decreasing level of available nitrogen.