Spatio-temporal evolution characteristics and simulation prediction of carbon storage: A case study in Sanjiangyuan Area, China

Understanding the relationship between land-use patterns and regional carbon storage, as well as predicting future land-use changes for regional carbon sink and emission management, are of immense significance. This study utilized land-use data from 1990, 2000, 2010, and 2020, as well as the InVEST model, to evaluate the spatiotemporal evolution of carbon storage in the Sanjiangyuan area over the past three decades. Furthermore, predictions for carbon storage in 2035 were presented using the PLUS model. The findings revealed the following key results: (1) the land types in the Sanjiangyuan area are mainly low cover grassland, medium cover grassland and unused land, among which unused land decreased significantly from 1990 to 2020, and the area of low cover grassland and wetland increased, which is the main reason for the increase of carbon storage. (2) Climatic-environmental and social-economic factors jointly influenced the land-use change in the Sanjiangyuan area. Except for the three types of grassland, the expansion of other land types was mainly influenced by climatic and environmental factors. (3) During 1990–2020, carbon storage in the source region of Sanjiangyuan area showed an overall upward trend, with a total increase of 39.97 × 107 t, and land-use change had a positive potential impact on carbon storage as a whole. (4) Under the natural change scenario, both carbon storage and regional carbon density increased in the simulation of 2035, and the potential impact of land-use change on carbon storage is positive. On this basis, the paper puts some suggestions forward to improve the carbon storage capacity of the Sanjiangyuan area in the future. This study provides valuable scientific insights for land-use management decision-making and promotes sustainable development of carbon storage functions in this region.