Assessment of Terrestrial Carbon Sinks: A Review of Methodological and Framework Limitations and Future Prospects

Ecosystem carbon sinks are a key indicator of terrestrial ecosystems' ability to absorb and store atmospheric CO₂. Their accurate assessment is of great significance for addressing global climate change and achieving carbon reduction targets. Due to limitations in the timeliness and resolution of satellite data, as well as the uneven global distribution of ground-based measurements, considerable uncertainty persists in current estimates of terrestrial ecosystem carbon sinks. This study systematically reviews research progress in remote sensing assessments of ecosystem carbon sinks both domestically and internationally. It summarizes the characteristics of mainstream technologies and analyzes common limitations in current research. These limitations include discrepancies between models and observed data, a lack of methods for identifying changes in carbon sinks, and insufficient analysis of driving mechanisms. We suggest improving real-time monitoring and multi-scale validation of carbon sink processes, increasing research into the factors and interactions driving changes in carbon sinks, and promoting the integration of multidisciplinary approaches to assess carbon sinks. It also recommends creating standardized systems and classification criteria for assessing carbon sinks, and developing optimization strategies that incorporate emerging remote sensing and artificial intelligence technologies into these assessments. The goal is to offer theoretical support and methodological guidance to help this field achieve higher precision, reliability, and practicality.