Temporal Patterns of Soil Microbial Biomass Carbon and Potential Enzyme Activities in Two Karst Forest Enclosure Areas

Forest enclosure is widely used in karst rocky-desertification landscapes, but field evidence remains limited for temporal soil microbial patterns. We characterized one naturally regenerated enclosure area (ZR) and one assisted-restoration enclosure area (RC) in Guizhou, China. Three fixed 10 m × 10 m plots in each continuous area were resampled in January, April, and October 2025. The data set includes source-reported microbial biomass carbon (MBC), organic-matter (OM) records used for transparent SOC/qMBC sensitivity calculations, potential enzyme source records, and amplicon-derived functional predictions. The primary confirmatory analysis addresses MBC variation within each continuous area across the three repeated sampling occasions. MBC increased numerically from January to October in all six fixed plots, and exact plot-blocked tests supported within-area temporal variation in RC (q = 0.0278) and ZR (q = 0.0093). Because each restoration history is represented by one continuous enclosure area, numerical RC–ZR contrasts are descriptive only. OM-derived SOC/qMBC, enzyme records, and FUNGuild/PICRUSt2 outputs are retained as transparent sensitivity or exploratory materials; they do not support claims about carbon-use efficiency, nutrient limitation, direct functional activity, or general restoration effects. The study retains the ecological context and full visual record of the original work while providing an explicitly bounded, reproducible case description.