Optimization of Reclamation Measures in a Mining Area by Analysis of Variations in Soil Nutrient Grades under Different Types of Land Usage—A Case Study of Pingshuo Coal Mine, China

The development of reclaimed mine soils is normally spatially heterogeneous, making the fine management and utilization mined lands difficult. Soil nutrient grading can provide a scientific basis for precise regulation soil nutrients, but few related studies are available in areas. This study aimed to quantify spatiotemporal variations grades under different land-use types area on Loess Plateau, China. was graded by four nutrients (soil potassium (SAK), phosphorus (SAP), total nitrogen (STN), organic matter (SOM)), variation features initial stage reclamation (i.e., cultivated land, grassland, forestland, barren land) were systematically characterized geostatistical analysis, pedodiversity correspondence analysis. results show that during five years after reclamation, most areas increased from Grade V VI I–IV, while improvements significantly heterogeneous. Notably, had distinct characteristics. land lowest SAP level, whereas it highest proportion, medium–high SAK, STN, SOM (88.3, 100.0, 100.0%, respectively). In terms quantitative structure, richness index (S?, 2.5) Shannon’s entropy (H?, 0.7) evenness (E?, 0.8). These suggest relatively high balanced with homogeneity among types. grassland considerable improvement all (especially SAP; 95.6% grades); however, its heterogeneous (S? = 4.5, E? 0.7). As second-most type 4.0, 0.8), forestland low SAP, SAK levels due uptake storage tree species, proportion reached (36.4%) medium (100.0%) community productivity. which received fertilization an additional three years, imbalanced nutrients. It (98.0%); contrast, proportions low-grade (69.0 32.9%, respectively) Based above comprehensive characterization grade variation, guidance given optimization measures.