A theoretical framework for the methodology of carbon sink assessment in China: A literature review

• Establish a theoretical framework for carbon sink assessment. • Identify uncertainty drivers in the carbon sink assessment scheme systematically. • Propose a common carbon sink assessment method in China. Ecosystem carbon sinks play a crucial role in mitigating climate change by sequestering carbon within ecosystems, thereby reducing atmospheric CO₂ concentrations. There is a lack of a unified theoretical framework and applicability research on methods for assessing carbon sinks. Therefore, this study comprehensively analyzes all mainstream carbon sink assessment methods. The selection of the Carnegie-Ames-Stanford approach (CASA) model known for its robust applicability, is made after evaluating principles, heterogeneity, and practicality. Then based on CASA model, through systematic literature analysis, we construct a three-parameter synergistic improvement theoretical framework. And taking China as a case study, this study develops the carbon sink assessment methodology applicable to sub-regional implementation. This will reduce the uncertainty in China's carbon sink assessment and provide a basis for the implementation of carbon sink management strategies to combat climate change.