diazotrophs during corpse decomposition

Corpse decomposition affects soil organisms through the formation of “cadaver decomposition islands” (CDIs). Soil diazotrophic microbes possess essential ecological functions on nitrogen input and nutrient cycling in the terrestrial ecosystem. However, our knowledge about how soil diazotrophic communities respond to corpse decomposition is lacking. In this study, we focused on the succession patterns and biological interaction of nitrogen-fixing microorganisms during animal (Ochotona curzoniae) corpse decomposition in terrestrial ecosystems by targeting nifH gene with high-throughput sequencing. Our results revealed the dynamics of the nifH-type diazotrophic community under corpse interference. Corpse decomposition reduced the a diversity and significantly impacted on ß diversity of nifH-diazotrophic community across different decomposition stages. The divergent succession of diazotrophic community occurred under corpse pressure. Furthermore, the relative importance of stochasticity to the community assembly was improved by corpse decomposition, while the importance decreased over decomposition time. Cadaver decay also simplified the diazotrophic networks and weakened the biological interactions among diazotrophic populations. Notably, NH4-N was the most important factor affecting diazotrophic community, followed by time and TC. In brief, this work emphasized that corpse decomposition perhaps influences the process of biological nitrogen fixation (BNF) by altering soil diazotrophic communities, which is of great significance for understanding the terrestrial ecosystems functions.