Ground-Dwelling Insects as Bioindicators for Post-Mining Restoration in Pangkep Regency, South Sulawesi, Indonesia

Abstract

Ground-dwelling insects are key indicators of ecosystem health due to their roles in decomposition, nutrient cycling, and the dynamics of food webs. Post-mining lands often suffer from environmental degradation, requiring effective reclamation strategies. This study assessed the relationship between microclimate and ground-dwelling insect composition in reclaimed limestone and clay mining sites at PT Semen Tonasa, Pangkep Regency, South Sulawesi, Indonesia. Insects were sampled using pitfall traps across sites with different reclamation years. Diversity indices Shannon-Wiener (H'), richness (R), evenness (E), dominance (D), correlation analysis, and principal component analysis (PCA) were used to evaluate patterns. A total of 23,294 individuals representing 36 species, 26 families, and nine orders were recorded. Dominant species included Dolichoderus thoracicus and Carebara diversa, indicating high ecological adaptability. The highest diversity (H' = 2.09) and richness (R = 3.32) were found in the 2017 clay site, while the 2018 limestone site had the highest evenness (E = 0.85) and dominance (D = 0.36). Correlation analysis showed that soil temperature and humidity were significantly positively associated with insect diversity (r>0.60, p<0.05). PCA revealed air temperature, humidity, soil pH, and light intensity as key factors influencing insect communities, accounting for 52.08% (PC1) and 28.63% (PC2) of the variance. These findings highlight the importance of microclimate-informed management for successful post-mining land restoration.