Carbon Accounting in Forest Ecosystems Under Alternative Management Regimes: Distributional Implications for Baselines and Emission Factors

Carbon Accounting in Forest Ecosystems Under Alternative Management Regimes: Distributional Implications for Baselines and Emission Factors

Juliet Isnino Eisimsidele, Cathal O’Donoghue, Patrick McGetrick

University of Galway

 

Abstract

Robust carbon accounting in forest ecosystems depends critically on baseline selection, emission factors, and temporal boundaries, yet these elements are highly sensitive to forest management decisions across the forest life cycle. Building directly on existing work on life-cycle economic and social returns to afforestation, this study examines how alternative management regimes, specifically thinned versus unthinned systems, shape carbon accounting outcomes from pre-planting baselines through harvest and post-harvest use, with particular attention to the timing and distribution of carbon benefits.

An integrated life-cycle carbon accounting framework is applied, combining forest growth modelling with carbon stock and flow analysis across full rotation cycles. The approach incorporates management-specific baselines, rotation length, thinning interventions, and the allocation of harvested timber to long-lived construction products, reflecting assumptions consistent with national greenhouse gas inventory practice. The analysis captures both in-forest carbon stocks and post-harvest carbon storage over time by linking forest growth dynamics with harvested wood product pathways. Sensitivity analyses are used to assess uncertainty related to baseline definition, temporal scaling, and key accounting parameters.

Preliminary results indicate systematic differences in both the magnitude and timing of carbon sequestration across management regimes. Unthinned systems concentrate carbon stocks earlier in the rotation. In contrast, thinned systems redistribute a greater share of carbon benefits to later stages through harvested wood products and extended storage beyond the forest stand. These variations affect the representation of mitigation performance within standard reporting periods used in national greenhouse gas inventories and influence implied emission factors.

This research provides empirical evidence relevant to ongoing debates on baseline definition, emission factor design, and Measurement, Reporting and Verification (MRV) by explicitly linking forest management decisions, life-cycle dynamics, and distributional carbon outcomes. The findings support the development of decision support tools and accounting frameworks that better reflect the long-term dynamics of afforestation systems, thereby improving the policy relevance of forest-based climate mitigation strategies within EU and international contexts.