Effect of karst rocky desertification on soil fungal communities in Southwest China

Abstract

ABSTRACT. Karst mountainous ecosystems are associated with karst rocky desertification (KRD), which can greatly impact soil structure and function. Despite the importance of soil microbes as a major factor maintaining ecosystem stability, we know little about the effect on soil fungal communities of KRD in karst regions. We investigated this relationship across a gradient of KRD soils from Guizhou, China by polymerase chain reaction and denaturing gradient gel electrophoresis (PCR-DGGE). Fungal diversity indices (Shannon-Wiener, richness, and evenness) significantly differed (P < 0.05) based on KRD severity, being lowest in moderately affected areas. Cluster analysis showed that the five sites examined clustered into two main groups according to KRD grade (high and low). Moreover, a homology search using sequences recovered from PCR-DGGE bands showed that the dominant fungi in each community varied remarkably, and included Aspergillus, Aphanoascus, Blastomyces, Fusarium, Glomus, Geomyces, Gibberella, Mortierella, Tetracladium, and Tumularia species, and an unclassified group. In conclusion, these findings demonstrate that KRD has a significant impact on soil fungal communities.

Total nitrogen is the main soil property associated with soil fungal community in karst rocky desertification regions in southwest China

“…Specifically, results showed that fungal communities in NKRD and SKRD were distinguishably different. This finding is congruent to the previous studies 10 , 34 . The richness of the fungal community in SKRD was slightly lower than that in NKRD.…”

“…The change in soil fungal community along with the KRD progression implies a mutual impairment between deteriorated ecosystems and simplified microbial communities. Indeed, previous studies demonstrated that the change in soil microbial community, as well as the loss of soil biodiversity, endangered the functionality and sustainability of the ecosystem 34 – 37 . Moreover, changes in soil fungal communities impact the nutrient cycling, especially the litter decomposition and nitrogen reincorporation, which liberate nitrogen back to above-ground communities.…”

Effects of Different Land Use Types and Soil Depth on Soil Nutrients and Soil Bacterial Communities in a Karst Area, Southwest China

“…Therefore, the rational use of land and soil depths in karst areas is critical. Recent reports highlight that land use type, revegetation process, and rocky karst desertification influence the structure and diversity of microbial communities [7][8][9][10]. However, the coupled influence of land use and soil depth on the composition and structure of soil microbial communities remains unknown.…”

The characterization of microbial communities and associations in karst tiankeng

“…The keystones of Bradyrhizobium and Steroidobacter play a key role in organic matter decomposition and nutrient cycling by connecting other microbial members in the network. In addition, fungal keystones of Fusarium are ubiquitous in karst ecosystems ( Wang et al, 2016 ). Fusarium can secrete cellulase to decompose carbon, and participate in the dissolution of soil insoluble phosphorus, effectively improving the acquisition of phosphorus by plants ( Yang et al, 2018 ).…”