Mineral protection and molecular architecture synergistically drive recalcitrant organic carbon accumulation during vegetation restoration in a subtropical region

The study aimed to uncover the mechanisms underlying soil recalcitrant organic carbon accumulation during the karst vegetation restoration, with its focus on comparing the relative contributions of plant-derived lignin and microbial-derived carbon to organic carbon stabilization. In this study, a space-for-time substitution approach was used, selecting three land-use types—cropland, shrubland, and secondary forest—representing a restoration chronosequence.

A total of 54 topsoil samples (0–15 cm) were collected.2 Overview of Data ContentThe dataset contains experimental analysis results for 54 soil samples, including the following major variable groups:(1) Soil Organic Carbon FractionsTotal soil organic carbon (SOC)Labile organic carbonRecalcitrant organic carbon (ROC)(2) Molecular diversitySimpson’s indexShannon diversity, HRichnessPielou's evenness Index, J'(3) Relative abundance of functional groupsAromaticFatty acidLipidN-containingLigninPolysaccharidesulfo-compoundunspecifiedPlant-sourceMicrobial-source(4) Network Topology ParametersNodesEdgesGraph DensityAverage DegreeBetweennessTransitivityModularityAverage Path LengthEccentricityCloseness CentralityHarmonic Closeness CentralityClustering(4)Soil Biotic and Abiotic VariablesTotal nitrogen, total phosphorus, soil stoichiometric ratiosMicrobial biomass carbonDissolved organic carbonLabile organic nitrogenSoil pH, Soil BD,exchangeable calcium (Ca2+) and magnesium (Mg2+)Iron and aluminum oxides (free, short-range ordered)3 Data Format and StructureFile format: Excel (.xls)Number of samples: 54Number of variables: 49 columns (including sample ID, UTM coordinates, land-use type, and all measured variables)Units:Carbon, nitrogen, and phosphorus indicators: g kg-1 or mg kg-1Aromatic, Fatty acid, Lipid, N-containing, Lignin, Polysaccharide, Sulfo-compound, Unspecified, Plant-source, Microbial-source: %pH, Nodes, Edges, Graph Density, Average Degree, Betweenness, Transitivity, Modularity, Average Path Length, Eccentricity, Closeness Centrality, Harmonic Closeness Centrality, Clustering: dimensionlessExchangeable cations: cmol kg-14 Brief