The Impact of Different Combinations of Organic Fertilizers on Residual Soil and Potted Plants in Alpine Mining Areas, West China

This study addresses how to overcome the challenges facing ecological restoration and vegetation recovery in alpine mining areas via indoor controlled pot experiments. The soil layer was recon-structed using a mixture of granular organic fertilizer, sheep manure, and mining slag, and manually sowed with a mixture of five types of grass seeds after potting to assess the impact of dosage of granular organic fertilizer and ratios of sheep manure to mining slag. Results indicate that the dosage of granular organic fertilizer significantly impacted plant characteristics, soil available nitrogen, phosphorus, potassium and pH (P < 0.01), and show significantly positive correlation with the number of dead seedlings. Sheep manure significantly affects soil available phosphorus and bulk density (P < 0.01). The highest grass density and biomass occurred with zero organic fertilizer dosage and a volume ratio of 1:3 between sheep manure and soil (M1S4), indicating that sheep manure effectively enhances seedling emergence. The dosage in the potted experiments is approximately six times higher than that in the alpine mining field. A dosage of granular organic fertilizer exceeding 1.5 kg/m²results in seedling mortality. Therefore, the dosage of granular organic fertilizer in restoration in alpine mining areas should not exceed 9 kg/m².