Integrated Assessment of Ecosystem Carbon Storage and Ecological Risk Index Under Multi-Objective Driven Approach: A Case Study of the Karst Ecologically Fragile Area in Guangxi

ABSTRACT: In the context of global climate change, enhancing ecosystem carbon storage (CS) capacity and reducing ecological risk have become essential pathways toward achieving carbon neutrality. Land use/land cover change (LUCC), as a key factor influencing both CS and ecological security, has garnered widespread attention in recent years. However, most existing studies have focused on small-scale regions, lacking comprehensive assessments at the provincial level under multiple scenarios. To address this gap, this study takes the ecologically fragile karst region of Guangxi as a case study. Based on the PLUS-InVEST model, this study construct three land use scenarios (natural development, economic development, and ecological protection) to simulate land use changes by 2030, and then conduct an integrated assessment of the dynamics of ecosystem CS and the spatial distribution of landscape ecological risk under different scenarios. The results show that: (1) From 2000 to 2020, land use in Guangxi has shown a general trend of decreasing farmland area and increasing construction land. CS has exhibited notable spatial heterogeneity over time, with an overall upward trend, particularly in forest-rich areas where CS has increased significantly. (2) By 2030, CS will be jointly driven by land use patterns, climate change, and socioeconomic factors under different scenarios, with the ecological conservation scenario leading to the greatest increase in CS. (3) Spatial auto-correlation and LISA cluster analyses reveal a spatial coupling pattern of high carbon–low risk and low carbon–high risk, suggesting that ecological conservation measures can effectively enhance carbon sequestration. These findings provide scientific support for land use optimization, ecological protection and CS management in Guangxi under the carbon neutrality goal, and offer valuable insights for land use planning and ecological risk regulation in ecologically fragile karst regions.