Revisiting the Role of China's Protected Areas in Carbon Storage

It is widely expected that conservation efforts within protected areas (PAs) can achieve multiple conservation objectives simultaneously. PAs established primarily for biodiversity conservation also contribute to increasing carbon storage in terrestrial ecosystems. However, there is a lack of quantitative studies on the role of China's existing PAs in carbon storage. We proposed an integrated approach to estimating the carbon density of terrestrial ecosystems in China, based on a modified Integrated Valuation of Ecosystem Services and Trade-offs model. Through a statistical matching method, we evaluated the conservation effectiveness of PAs in carbon storage during 2020–2050. Under the moderate emission scenario (SSP2-RCP4.5), the average carbon density of PAs is projected to 168.3 Mg C ha⁻¹, an increase of 14.2% compared to 2020. In contrast, under the low emission scenario (SSP1-RCP2.6) and high emission scenario (SSP5-RCP8.5), the average carbon density of PAs is projected to decrease by 4.8% and 4.6%, respectively. By 2050, approximately 45%–47% of PAs are expected to experience effective conservation in carbon storage, with about 80% of PAs maintaining their current effectiveness during 2020–2050. Additionally, in view of area proportion, 34.3%–36.2% of PAs will remain effective, while 1.8%–4.0% are projected to transition from ineffective to effective. PAs with conservation effectiveness in carbon storage were predominantly located in humid and mid-to-high-altitude regions. Given the spatial mismatch among existing PAs, priority areas for carbon storage conservation, and effective areas for carbon storage conservation, our findings underscore the necessity of expanding China's PAs to achieve the additional benefits of PAs in carbon storage conservation.