Integrated stock and flow dynamics for comprehensive carbon offset evaluation A system dynamics analysis of natural and farming ecosystems

Author

Sasaki, Takahiro and Suzuki, Godai and Funabashi, Masatoshi

Abstract

Carbon credits are gaining prominence as a strategy to mitigate climate change by reducing greenhouse gas emissions. This study integrates stock and flow using a System Dynamics (SD) approach to evaluate the carbon offset potential of different farming practices in comparison to natural forests. We especially compare high- and moderate-input conventional monoculture farming and synecoculture (an alternative farming system) by modeling their carbon budgets, including biomass growth, soil carbon sequestration, harvested biomass, and agricultural inputs. Simulated results reveal that while conventional monoculture has high productivity, it also leads to significant carbon emissions, leading to a positive carbon budget (increase of GHGs in the atmosphere) in total. In contrast, synecoculture demonstrates a net negative carbon budget, effectively removing more carbon from the atmosphere and sequestering it in biomass and soil. Although being under a trade-off with agricultural productivity in the high-input scenario, the conversion from conventional monoculture to synecoculture is revealed to offer greater offset potential than establishing a natural forest within a 20-year time scale. The integrated evaluation of stock and flow could help disentangle the complex carbon budget of human-managed ecosystems and contribute to increasing the accuracy of evaluation, as well as discovering novel offset opportunities beyond the evaluation of stock on site.