Effects of pattern dynamics on carbon storage capacity in the Qinghai-Tibetan Plateau from 1980 to 2020

The synergistic effects of landscape composition and spatial configuration are critical for regulating terrestrial carbon storage. However, their dynamic relationships and driving pathways remain poorly understood, especially in high-altitude semi-arid ecosystems. As the world's largest alpine carbon sink, the Qinghai Tibetan Plateau (QTP) is undergoing rapid landscape transformation, threatening the stability of its carbon storage function. This study integrates the InVEST carbon storage model with Fragstats metrics to investigate how multiscale landscape dynamics influence carbon storage services on the QTP. From 1980 to 2020, grasslands experienced the most significant land conversion (468 × 10³ km²), primarily into unused land (75.39%), forest (15.32%), and water (7.67%). These transitions increased landscape fragmentation and diversity while reducing aggregation and connectivity. Carbon storage was positively correlated with Aggregation Index and Largest Patch Index, but negatively correlated with Patch Density and Edge Density. Over four decades, total carbon storage (TCS) decreased by 4.86% from 270 × 10⁸ to 258 × 10⁸ t driven largely by a 29 × 10⁸ t loss in grassland carbon, partly offset by an 11 × 10⁸ t gain in forests. These findings help improve land use planning and management to boost carbon storage in high-altitude areas.