Revegetated shrub species recruit different soil fungal assemblages in a desert ecosystem

Abstract

Revegetation with xeric shrubs is a widely applied measure for restoring degraded ecosystems in the deserts of northern China. However, knowledge on the soil fungal assemblages in revegetated shrubs still remains veiled. This study aimed to evaluate how soil fungal diversity and composition respond to shrub species. We characterized soil fungal communities in three different shrublands (Artemisia ordosica, Salix psammophila, and Caragana microphylla), which had been planted on bare sandland for about 20 years, in the Mu Us Desert in northern China, using high-throughput 18S rRNA gene sequencing. The relationships of fungal community diversity and composition with environmental variables were explored by regression analysis and Mantel test, respectively. The dominant phyla across the studied samples were Ascomycota and Basidiomycota. Compared to bare sandland, fungal diversity was significantly greater in A. ordosica and C. microphylla but not in S. psammophila. There was a positive linear relationship between soil fungal and understory plant diversity. A. ordosica and C. microphylla shrublands showed the greatest relative abundance of Ascomycota; S. psammophila shrubland showed the greatest relative abundance of Basidiomycota. In terms of functional groups, the highest relative abundance of ectomycorrhizal fungi and the lowest relative abundance of pathogenic fungi were found in S. psammophila shrubland. Soil collected from A. ordosica shrubland showed the highest relative abundance of arbuscular mycorrhizal fungi. Variations in fungal diversity and assemblages were directly affected by the revegetated shrub species. The strong correlation of the fungal community and shrubs provides a better understanding of soil organic carbon sequestration and plant–soil interaction in different revegetated shrublands.