Figures and data
The overall degradation rates of soil extracellular 16S rRNA gene amplicon fragments and their influential factors.
(a) The GAPDH F-tagged 16S rRNA gene amplicon fragment abundance at different incubation time points. (b) and (c) The degradation rate constants of soil extracellular 16S rRNA gene amplicon fragments across the study sites and different ecosystem types. (d) The factors influencing extracellular 16S rRNA gene degradation rates. (e) The influencing factors for the overall degradation rates of soil extracellular 16S rRNA gene amplicon fragments revealed by structural equation modeling. Orange and green lines indicate positive and negative relationships, respectively. Solid and dashed lines indicate significant and non-significant relationships, respectively. Path coefficients are denoted by numbers adjacent to the arrows, with arrow width reflecting their strength. (f) The influence of soil moisture on the degradation rates of soil microbial eDNA. Significance levels are indicated as follows: * P < 0.05, ** P < 0.01, and *** P < 0.001. Moisture: soil moisture content; Abundance: prokaryotic abundance; NMDS1: the scores at the first axis of the NMDS ordination of prokaryotic community profiles; MAP: mean annual precipitation; Richness: soil prokaryotic richness; NMDS2: the scores at the second axis of the NMDS ordination of prokaryotic community profile; TK: soil total potassium contents; MAT: mean annual temperature; AP: soil available phosphorus content; TN: soil total nitrogen contents; and TOC: soil total organic carbon content.
The sequence-specific degradation rates of soil exogenous extracellular 16S rRNA gene amplicon fragments.
(a) Soil GAPDH F-tagged 16S rRNA gene richness. (b) The nonmetric multidimensional scaling (NMDS) ordination of the community profiles based on GAPDH FLtagged 16S rRNA gene amplicon fragments at different incubation time points. (c) The number of GAPDH F-tagged 16S rRNA gene ASVs within different degradation rate ranges.
The difference in sequence-specific degradation rates of soil extracellular 16S rRNA gene amplicon fragments and their influencing factors.
(a) The paired comparison of degradation rates among different ASVs. In the heatmap, each cell represents a pairwise comparison between two ASVs. Blue indicates that the degradation rate of the ASVs listed in the row (row ASVs) is significantly lower than that of the ASVs listed in the column (column ASVs); red indicates that the row ASVs has a significantly higher degradation rate than the column ASV. A positive t value indicates that the row ASVs degrades significantly faster than the column ASVs; a negative t value indicates the opposite. Significance levels are indicated as follows: * P < 0.05, ** P < 0.01, and *** P < 0.001. (b) The relationships between the sequence-specific degradation rate profiles and environmental factors. NO3--N: soil NO3--N contents; NH4+-N: soil NH4+-N contents; TN: soil total N contents; TP: soil total P contents; TK: soil total K contents; AP: soil available P contents; TOC: soil total organic carbon content; MAT: mean annual temperature; and MAP: mean annual precipitation.
The differences in the abundance, richness, Shannon, and community composition between total and PMA-treated soil prokaryotes.
(a) The abundance of total and PMA-treated soil prokaryotes. (b) and (c) The richness and Shannon index of total and PMA-treated soil prokaryotes. (d) The differences between the relative abundance of total and intracellular ASVs. The red points represent the prokaryotic taxa exhibiting statistically significant differences. (e) The nonmetric multidimensional scaling (NMDS) ordination of total and PMA-treated soil prokaryotes. Different colors represent samples from different sites. (f) The Bray-Curtis dissimilarity between total and PMA-treated soil prokaryotes.
Effects of eDNA exclusion on soil prokaryotic community composition and its relationships with environmental factors.
(a) The taxa with significant differences between total and intact cell prokaryotic communities. P1: Thermoplasmatota; P2: Nitrospirota; P3: Fibrobacterota; P4: Entotheonellaeota; P5: Elusimicrobiota; P6: Armatimonadota; P7: Myxococcota; C1: Thermoplasmata; C2: Nitrospiria; C3: Vampirivibrionia; C4: Clostridia; C5: Bacilli; C6: Armatimonadia; C7: Chthonomonadetes; C8: Polyangia; C9: Blastocatellia; C10: Parcubacteria; C11: Bacteroidia; C12: Thermoleophilia; O1: Nitrospirales; O2: Abditibacteriales; O3: Clostridiales; O4: Bacillales; O5: Armatimonadales; O6: Pyrinomonadales; O7: Bryobacterales; O8: Chitinophagales; O9: Rubrobacterales; O10: Propionibacteriales; and O11: Corynebacteriales. (b) The relationships between soil prokaryotic community profiles and environmental factors. NO3--N: soil NO3--N contents; NH4+-N: soil NH4+-N contents; Moisture: soil moisture content; MAT: mean annual temperature; MAP: mean annual precipitation; TP: soil total P contents; TK: soil total K contents; and TOC: soil total organic carbon contents.
