Continuous growth of human footprint risks compromising the benefits of protected areas on the Qinghai-Tibet Plateau

Protected areas (PAs) are the critical societal tool to preserve biodiversity and ecosystem services (ESs), but human disturbances frequently threaten them. Here, we used multiple data sources to map the human footprint as a proxy for identifying the intensity of human activities on the Qinghai-Tibet Plateau and therein nature reserves (NRs, the primary category of PAs in China). We found that the human footprint on the Qinghai-Tibet Plateau has increased by 22% since 2000, and on average, human pressure inside NRs was 60% lower than outside. However, human pressure was identified in the majority of the NRs, with only 30% of protected land free from any measurable pressure. From a total of 53 NRs, 28 showed over 10% increase in human footprint, and 6 NRs had over 70% of their extent under intense human pressure (human footprint score≥4). Furthermore, a higher proportion of ESs in NRs is subjected to high levels of human pressure and are therefore at risk, particularly soil and water retention. The applied regression model revealed that large NRs are more resilient to human pressure than NRs with the longer establishment. The continuous human footprint increase may hinder the current and future ESs supply. Our analysis shows evidence-based results to promote the mitigation of human pressures in PAs.