The chapter discusses the significant impact of biodiversity loss on global terrestrial carbon storage. Natural ecosystems store substantial amounts of carbon, and their carbon sequestration potential is closely linked to biological diversity. However, many carbon sequestration models fail to account for the role of biodiversity in carbon storage. The study assesses the consequences of plant biodiversity loss under various climate and land-use change scenarios, linking a macroecological model projecting changes in vascular plant richness with empirical data on biodiversity-biomass relationships. The results indicate that biodiversity declines due to climate and land-use changes could lead to a global loss of between 7.44-103.14 PgC (global sustainability scenario) and 10,87-145.95 PgC (fossil-fueled development scenario). This highlights a self-reinforcing feedback loop where higher levels of climate change lead to greater biodiversity loss, which in turn leads to greater carbon emissions and further climate change. Conversely, conserving and restoring biodiversity can help mitigate climate change. The study emphasizes the importance of integrating biodiversity into climate change mitigation efforts and suggests that maintaining and enhancing plant species diversity within natural vegetation can increase carbon storage potential.The chapter discusses the significant impact of biodiversity loss on global terrestrial carbon storage. Natural ecosystems store substantial amounts of carbon, and their carbon sequestration potential is closely linked to biological diversity. However, many carbon sequestration models fail to account for the role of biodiversity in carbon storage. The study assesses the consequences of plant biodiversity loss under various climate and land-use change scenarios, linking a macroecological model projecting changes in vascular plant richness with empirical data on biodiversity-biomass relationships. The results indicate that biodiversity declines due to climate and land-use changes could lead to a global loss of between 7.44-103.14 PgC (global sustainability scenario) and 10,87-145.95 PgC (fossil-fueled development scenario). This highlights a self-reinforcing feedback loop where higher levels of climate change lead to greater biodiversity loss, which in turn leads to greater carbon emissions and further climate change. Conversely, conserving and restoring biodiversity can help mitigate climate change. The study emphasizes the importance of integrating biodiversity into climate change mitigation efforts and suggests that maintaining and enhancing plant species diversity within natural vegetation can increase carbon storage potential.