Do social capital spillovers affect CO2 emissions?

While numerous studies have examined the factors influencing CO₂ emissions, the impact of social capital on CO₂ emissions remains an important yet relatively understudied area. This study addresses a critical gap in the literature by examining the spatial spillover effects of social capital and its dimensions — trust, norms, and participation — on CO₂ emissions. Using the Spatial Durbin Model (SDM) and data from 28 Iranian provinces spanning from 2005 to 2020, this study captures both direct and spillover effects of social capital. The results indicate that the direct, spatial spillover, and total effects of social capital on CO₂ emissions are negative and statistically significant. Similarly, the direct, spatial spillover, and total effects of trust, norms, and participation, as key dimensions of social capital, are also negative and statistically significant. Importantly, the findings reveal that the long-run effects of social capital and its dimensions are more substantial than the short-run effects, suggesting that the environmental benefits of social capital intensify over time. By uncovering the mechanisms through which social capital influences emissions reduction, this research underscores the importance of regional collaboration and provides valuable insights for evidence-based policymaking.