Three decades of spatiotemporal dynamics in forest biomass density in the Qinba Mountains

The forest ecosystem plays a pivotal role in the global carbon cycle and is crucial for investigating atmospheric carbon exchanges. Forest biomass, a fundamental quantitative measure of the forest ecosystem, serves as a critical indicator for forest carbon stocks and carbon sequestration capacity. This study utilizes the GIMMS NDVI3g dataset to downscale forest inventory data spanning from 1989 to 2018, creating a 1 km resolution map of forest biomass density in the Qinba Mountains. The density initially decreased but has been increasing since 2004. The northern region of the Qinba Mountains exhibits a high forest biomass density (>100 Mg/hm(2)), while the southern region has relatively lower biomass density. This study provides the longest-term estimation of forest biomass density in the Qinba Mountains to date. It serves as a foundation for regional-scale forest carbon sequestration management and carbonization decision-making. This research is of significant importance for enhancing understanding of regional carbon cycling and supporting sustainable ecological development.