Recovery of soil carbon pools and C–N stoichiometry under drought in degraded tin-mined soils using organic, inorganic, and bio-amendments

Abstract. Rahayu, Erdaswin F, Rosariastuti R, Dewi WS, Fatimah, Herawati A, Ichsan N. 2025. Recovery of soil carbon pools and C–N stoichiometry under drought in degraded tin-mined soils using organic, inorganic, and bio-amendments. Asian J Agric 9: 818-830. Large-scale tin mining on Bangka Island, Indonesia, has severely degraded soils, resulting in low carbon reserves and imbalanced C–N stoichiometry, particularly under seasonal drought. This study evaluated the effectiveness of an integrated amendment strategy to restore soil carbon pools and improve C–N stoichiometry under these challenging conditions. A 100-day screenhouse experiment was conducted on degraded tin-mined soil using a Completely Randomized Design. Treatments included municipal compost, dolomite, Lactic Acid Bacteria (LAB), and NPK fertilizer, applied individually and in combination. Key physicochemical properties, carbon pools, stoichiometric ratios, and their interrelationships were analyzed using ANOVA, Redundancy Analysis, and Pearson correlation. The integrated combination treatment was synergistically superior (ANOVA, p