Population Pressures, Institutional Quality and Environmental Sustainability in Sub‐Saharan Africa: Nonlinear Dynamics and Regional Heterogeneity

Rapid population growth, environmental degradation and institutional constraints continue to shape environmental sustainability in Sub‐Saharan Africa (SSA), yet evidence on nonlinear demographic dynamics, governance moderation and regional differences remains limited. This study examines the determinants of environmental sustainability using panel data for 45 SSA countries from 2000 to 2023. A multidimensional environmental sustainability index (ESI), incorporating CO 2 emissions, forest cover, PM2.5 pollution and energy use, is developed to capture broader environmental conditions. The findings indicate that government effectiveness is negatively associated with environmental sustainability, while economic development is positively associated with environmental outcomes. Nonlinear analysis identifies a U ‐shaped relationship for population density and an inverted U ‐shaped relationship for energy use. Governance also moderates the relationships between population density, energy use and environmental sustainability, although only the population‐density threshold appears economically meaningful. Regional differences underscore the importance of context‐specific environmental governance, land‐use planning and cleaner energy transitions to support environmental sustainability across SSA.