Abstract: Peri-urban plantations in the Mediterranean are often degraded due to human inactivity and climate change, leading to a loss of ecosystem services and biodiversity. This study investigates the impact of different thinning practices on carbon sequestration and tree stability in a degraded peri-urban plantation in the Italian Apennines, six years after thinning. Three treatments were compared: (a) moderate thinning from below (− 25% biomass), representing the typical practice; (b) intense selective thinning (-35% biomass), representing an innovative approach; and (c) no management as the control. Growth projections were used to estimate carbon recovery for these treatments, based on site-specific models calibrated with real data. The results show that both thinning approaches increased carbon sequestration over time, with the innovative thinning achieving a 7% higher annual carbon sequestration rate than traditional thinning and 8% more than the control. Estimated payback times were 9 years for recovering the harvested volume in both thinning approaches, 10 years for innovative thinning to surpass traditional thinning, 17 years for innovative thinning to surpass the control, and 24 years for traditional thinning to surpass the control. Additionally, tree mechanical stability improved significantly in both thinning treatments after two years, with further increases observed in the innovative thinning group after six years. These results suggest that selective thinning can accelerate forest recovery and carbon sequestration, especially in areas with high stem density, where it can reduce the negative impacts of tree mortality and deadwood accumulation. However, careful planning is required to mitigate potential short-term stability issues, particularly in challenging environments (e.g., windy conditions, steep slopes). Forest management strategies should therefore aim to balance growth, carbon storage, and tree stability, considering both long-term sustainability and local environmental conditions. The findings are particularly relevant for current climate change mitigation strategies, emphasizing that thinning should be carefully tailored to forest type and conditions to maximize benefits in carbon credit generation and sustainable forest management practices.

Key words: Peri-urban plantations, Carbon sequestration, Thinning, Payback time, Tree mechanical stability