Spatio-temporal characteristics and prediction of carbon storage in terrestrial ecosystems in Lijiang River basin

Evaluating ecosystem carbon storage is of great significance to regional ecological management. Using InVEST model and PLUS model, based on the interpreted land use data and future land use forecast data, the temporal and spatial characteristics of land use change and carbon storage in Lijiang River basin from 2000 to 2020 were studied, and the variation of carbon storage in different future scenarios was predicted. The results showed that land use change in Lijiang River basin from 2000 to 2020 was manifested in the reduction of cultivated land, forest land and grassland, and the increase in the area of ​​water, construction land and unused land. Under the influence of land use change, the carbon storage in Lijiang River basin decreased by 0.945×10⁶ t from 2000 to 2020, among which the decrease was the largest from 2015 to 2020. The high carbon storage areas were mainly distributed in the high altitude area of the northwest, southwest and east of the basin, while the low carbon storage areas were mainly distributed in the central plain of the basin and obviously expanded from 2000 to 2020, and the carbon reserves of Lingui, Xing'an and Lingchuan counties in the basin decreased significantly. According to prediction, the carbon storage of Lijiang River basin would further decrease under the natural development scenario in 2030, the carbon storage under the cultivated land protection scenario would increase by 0.345 × 10⁶ t compared with the natural development scenario, and the carbon storage under the ecological protection scenario would increase by 1.540 × 10⁶ and 1.195×10⁶ t compared with the natural development scenario and cultivated land protection scenario, respectively. The cultivated land protection scenario could protect the amount of cultivated land, but the expansion of construction land was limited to a great extent; the ecological protection scenario could enhance carbon sequestration capacity, but could not effectively control the reduction of cultivated land area. In the future national land spatial planning of Lijiang River basin, ecological protection and cultivated land protection measures needed to be comprehensively coordinated to enhance the regional carbon sequestration capacity and achieve green and sustainable development.