Intertemporal biomass and carbon stock dynamics in a managed Amazonian Forest

Abstract

Context: Managed tropical forests play a crucial role in climate regulation and in maintaining carbon stocks; however, integrated assessments that treat biomass and carbon as environmental assets remain limited. Originality/Contribution: This study integrates IPCC methodological approaches with the System of Environmental-Economic Accounting (SEEA) Central Framework to organize biomass and carbon stocks and flows as forest environmental assets under sustainable management. Objective: To evaluate the intertemporal dynamics of forest volume, biomass, and carbon stocks in a managed Amazonian forest. Methodology: Trees with a DBH ≥ 20 cm were analyzed in Annual Production Unit 4 of the Tapajós National Forest, from 2009 to 2022. Stem volume was converted into biomass, carbon, and CO₂ equivalents using conversion factors consistent with IPCC guidelines and regional references. Stock changes were estimated using the Gain–Loss and Stock-Difference methods, and exploratory multivariate analyses were performed to assess the structural and temporal coherence of forest variables. Results: Gross increment reached 87.38 m³ ha⁻¹, while total reductions amounted to 88.47 m³ ha⁻¹, i.e., forest volume was stable over the study period. After conversions, stability of biomass and carbon stocks was also observed, with minimal net emissions. Multivariate analysis revealed a temporal trajectory characterized by post-harvest structural reorganization followed by biomass accumulation within the monitored forest component. Conclusions: The results indicate that biomass and carbon stocks remained approximately stable in the monitored area throughout the study period. Environmental-economic accounting provided a consistent framework for organizing biomass and carbon stocks and flows, supporting the assessment of stock changes in managed Amazonian forests.

Keywords: Forest carbon, Forest biomass, Natural capital