Assessing carbon storage dynamics and policy impacts: Application of InVEST-PLUS framework in the Qinling Mountains, China

Mountainous regions play a vital role in global carbon sequestration, yet they are increasingly shaped by anthropogenic pressures and land-use changes. This study focuses on the Qinling Mountains in Shaanxi Province, China, to quantify historical land-use and carbon storage dynamics (1985–2020) and to project alternative futures to 2050. Using eight temporal snapshots of county-level data (n = 39), the study coupled the InVEST Carbon Storage and Sequestration module with a Markov-PLUS land-use simulator to model three scenarios: Natural Growth (NGS), Ecological Priority (EPS), and Tourism Development (TDS). The results show that forest expansion—from 66.04 % to 75.29 % of total land cover—raised carbon storage from 1652.66 Tg to 1732.19 Tg over the 35-year period. Spatially, carbon stocks increased markedly in the southern and eastern Qinling, consistent with ecological restoration and comparatively lower urban pressure, whereas northern areas experienced net declines associated with intensive urbanization. Scenario projections indicate continued carbon accumulation by 2050, with total storage reaching 1762.95 Tg under NGS, 1778.70 Tg under EPS, and 1767.02 Tg under TDS. EPS, which prioritizes ecological restoration, delivers the largest net increase relative to 2020 (+46.51 Tg), highlighting the carbon benefits of conservation-oriented policies. TDS yields intermediate gains, allowing moderate tourism-driven land conversions while largely maintaining forest cover. As a critical ecological barrier in central China, the Qinling Mountains require land-use strategies that balance economic development with ecological integrity and food- security constraints. The study provides a policy-relevant framework for guiding low-carbon development in mountainous regions. By integrating scenario-based modeling with spatial analyses, it illustrates how targeted afforestation, sustainable tourism, and adaptive land management can jointly strengthen carbon sinks and enhance environmental resilience. • Forest area increased by 7566 km² from 1985 to 2020, raising total carbon storage by 79.53 Tg. • Carbon storage is projected to increase under all scenarios to 2050; EPS delivers the largest gain (+46.51 Tg vs. 2020). • By 2050, TDS will reach 1767.02 Tg, slightly higher than NGS (1762.95 Tg). • Carbon gains concentrate in the southern/eastern Qinling, while the northern metropolitan fringe shows weaker gains or local losses.