Protected areas effectively resisted 33.8% of urban development pressures in China during 2000–2018

Protected areas (PAs) are the primary defense against biodiversity loss. Urban development and expansion have subjected PAs to significant pressure, as they are rapidly approaching. However, our understanding of the interaction between urban development and PAs in China when urbanization accelerated from 2000 to 2018 remains limited. To address this gap, we have realized the dynamic mapping of China's urban expansion and proposed the urban footprint intensity index (UFI) and PAs' UFI (PUFI) to quantify the spatial distribution of urban development and its potential pressure on PAs. Using the Generalized linear mixed-effects models, we also investigated how PAs limit the increase in UFI from multiple perspectives. Our results reveal that while China's urban areas continue to expand annually by 6101.3 km2, the distance between the protected area (PA) and the urban area is shrinking at a rate of 1.39 km per year, maintaining a logarithmic form. The PAs in the eastern China and the southern China always have higher PUFI values from 2000 to 2018. By contrast, those in the northern and western China have lower PUFI values in 2000, which increase dramatically by 2018. Across our study area, PAs have effectively acted as barriers to urban development, resisting a substantial 33.8% increase in UFI within their boundaries. Location and initial urban development conditions surrounding PAs are critical factors impacting their effectiveness in resisting urban development. These findings offer valuable insights for future assessments of the effectiveness of PAs in resisting urbanization on a global scale. Moreover, this study provide crucial guidance for fostering urban development along more sustainable trajectories, thereby ensuring the long-term conservation of PAs worldwide.