Abstract: The Tibetan Plateau is highly sensitive to global climate change, and is the controller for regional climate in the Pan-Third Pole region. On the Tibetan Plateau, soil carbon accounts for a high proportion of the ecosystem carbon and is extremely important for ecosystem carbon cycling. However, there are still plenty of uncertainties for current soil carbon storage estimation on the Tibetan Plateau, with different estimation methods also having great discrepancies. Here, we reviewed research progress on soil carbon storage on the Tibetan Plateau during the past 30 years, and compared the results of different studies. We also analyzed the spatial and temporal variation of soil carbon storage based on two kinds of influencing factors (inherent, such as geographical factor, soil property, vegetation type; and variable, such as climate change, human activities). In terms of estimation models and methods, the process models such as CENTURY and TEM, which consider multiple processes affecting soil carbon storage, had higher accuracy compared with the EVI and NDVI models, and interpolation estimation. Averaged across different studies, soil organic carbon storage in the top 20 cm of the alpine grasslands is about 10 Pg C (1 Pg=10¹⁵ g), and that in the top 200 cm of the alpine permafrost is approximately 16.5 Pg C. Soil inorganic carbon storage in the top 100 cm of the alpine grassland is about 14 Pg C. The soil carbon storage on the Tibetan Plateau decreases gradually from southeast to northwest. The effects of variable factors on soil carbon storage varied greatly. The estimation accuracy of soil carbon storage is affected by sampling location, data source type, estimation method, and soil depth. Future studies of soil carbon storage on the Tibetan Plateau should pay attention to establishing a common standard for soil carbon storage estimation. Under the common standard, the comparability among different studies is boosted. Meanwhile, expanding sampling area and sample size, increasing sampling depth and maintaining the temporal coherence among each sampling period can efficiently abate uncertainty in soil carbon storage estimation on the Tibetan Plateau. With these improvements, our understanding on Tibetan Plateau ecosystem responses to climate change would be advanced and our prediction on its future status be more accurate.

Key words: climate change, crop spatial allocation model, rice, spatial response, Northeast China.