Microbial moribunds after microbial biomass turnover (microbial residues) contribute to the formation and stabilization of soil carbon pools; however, the factors influencing their accumulation on a global scale remain unclear. Here, we synthesized data for 268 amino sugar concentrations (biomarkers of microbial residues) in grassland and forest ecosystems for meta-analysis. We found that soil organic carbon, soil carbon-to-nitrogen ratio, and aridity index were key factors that predicted microbial residual carbon accumulation. Threshold aridity index and soil carbon-to-nitrogen ratios were identified (~0.768 and ~9.583, respectively), above which microbial residues decreased sharply. The aridity index threshold was associated with the humid climate range. We suggest that the soil carbon-to-nitrogen ratio threshold may coincide with a sharp decrease in fungal abundance. Although dominant factors vary between ecosystem and climate zone, with soil organic carbon and aridity index being important throughout, our findings suggest that climate and soil environment may govern microbial residue accumulation.

No abstract

No abstract

No abstract

Soil enzyme activities in different plantation types and land use patterns could indicate changes in soil quality. This research was aimed at exploring the dynamics of soil enzyme activities involved in carbon, nitrogen and phosphorus cycling, and their responses to changes in soil physicochemical properties resulting from natural vegetation restorations and plantation schemes. Knowing about the effects of soil physicochemical properties on soil enzyme patterns is crucial for understanding ecosystem functions and processes. The study selected four main land-use types (natural forestland, natural grassland, artificial forestland, and artificial grassland) and one control plot (bare land) in the West Qinling Mountains, China, which is a typical landslide region. We collected the soil samples from each land use type and tested their physicochemical properties and enzyme activities compared with control land. The results showed that both natural vegetation restoration and artificial plantation schemes have significant effects on enzyme activities. Soil physicochemical properties explained 92.2% of the variation in soil enzyme activities for natural vegetation restoration, while it only explained 77.8% of the variation in soil enzyme activities for plantation schemes. Furthermore, natural vegetation had a greater effect than the plantation schemes on soil enzyme activities.