Pedogenic controls on nutrient retention and structure stability of fallow sandstone-derived soils in humid tropical environments

This dataset contains soil horizon-level data from four pedons (FL-1 to FL-4, 18 horizons total) excavated in Nkaliki, Abakaliki LGA, Ebonyi State, southeastern Nigeria, on soils derived from Ajali Sandstone parent material. The dataset supports the manuscript "Pedogenic and Structural Controls on Nutrient Retention in Coarse-Textured Sandstone-Derived Soils" submitted to Catena. Data include particle size distribution (sand, silt, clay), physical properties (bulk density, gravimetric moisture content), four computed structural and pedogenic indices (clay ratio, silt:clay ratio, complexed clay ratio, and structure stability index), soil chemical properties (pH, soil organic carbon, total nitrogen, available phosphorus, exchangeable bases, exchangeable acidity, effective cation exchange capacity, base saturation), elemental ratios (Ca:Mg, K:Mg, C:N, exchangeable sodium percentage), and available micronutrients (Zn, Cu, Mn). Particle size was determined by the hydrometer method, bulk density by the core method, and macro/micronutrients by standard wet chemistry and atomic absorption spectrophotometry. Structural indices follow established formulations (Dexter et al., 2008; Pieri, 1992). Full methodological details, units, and formulas for every variable are provided in the accompanying "Variable Descriptions" sheet. This dataset enables reproduction of the correlation, structural, and fertility analyses presented in the manuscript, and may be reused for comparative studies of nutrient retention and structural degradation in coarse-textured tropical soils.