Fig. 2: Variables affecting soil gas fluxes.
A Structural equation model (SEM) describing the effects of freeze-thaw strength, maximum thawing depth, soil properties, microbial diversity, stability, multielement, and multinutrient on multigas (CO2, CH4, and N2O fluxes). Three fluxes were grouped into one box in the model for graphical simplicity; however, the box does not represent latent variables. Single-headed arrows indicate the hypothesized direction of causation. Red solid lines indicate significantly positive relationships, blue solid lines indicate significantly negative relationships, red dotted lines indicate non-significantly positive relationships, and blue dotted lines indicate non-significantly negative relationships. B Bar graphs are the standardized effects from the SEM on three fluxes. Soil properties represent the first component by the principal component analysis for soil temperature, water content, pH, porosity, dry-sieving mean weight diameter, wet-sieving mean weight diameter, and belowground biomass. Asterisks indicate the statistical significance (***p < 0.001, **p < 0.01, and *p < 0.05).
