Reducing income gaps among Spanish Mediterranean municipalities: the role of environmental quality

Regional income trajectories are shaped not only by economic and social conditions, but also by the quality of the natural environment. This study examines the impact of environmental quality (EQ) on income growth in the Spanish Mediterranean region from 2015 to 2021, applying a beta convergence framework inspired by Barro and Sala-i-Martin (1992). To address spatial interdependencies and temporal dynamics, we employ a spatial seemingly unrelated regression (spatial SUR) approach. The results confirm significant beta convergence, with poorer municipalities growing faster. Environmental quality plays a pivotal role: higher coverage of natural protected areas (NPA) accelerates income growth and convergence, while nitrate-contaminated zones (NC) hinder both. This is the first spatial econometric analysis within the EU to assess the link between environmental quality and economic convergence at the micro-territorial level. The findings support stronger enforcement of the EU Biodiversity Strategy 2030 and call for a permanent environmental monitoring system to inform regional development policy and ensure that ecosystem conservation contributes effectively to inclusive and sustainable growth.