Evaluation of landscape sustainability of protected areas and identification of its correlation factors: a case study of Beijing, China

Context Protected areas (PAs) serve as robust safeguards for the ecological safety of urban areas, and positively affect their socioeconomic development. However, limited research that integrates both ecological and socioeconomic aspects to evaluate the role of PAs.Objectives In this study, we aimed to establish an evaluation framework for PAs that applies the concept of landscape sustainability and integrates ecological and socioeconomic functions to enhance understanding of the role of PAs. Additionally, we aimed to develop analytical framework for identifying the correlation elements of landscape sustainability of protected areas (PA-LS) and improving the understanding of the mechanisms underlying PAs.Methods This study focused on 38 PAs in Beijing, China. We established the PA-LS evaluation framework to evaluate the role of PAs by analyzing changes in their overall landscape services from 2000 to 2019, and in ecological and socioeconomic functions. Subsequently, an analytical framework was established to identify the correlation factors of PA-LS, focusing on four aspects: the fundamental characteristics of PAs, landscape patterns of PAs, impact of urban areas on PAs, and human well-being within a 5 km buffer of PAs.Results The landscape sustainability evaluation of Beijings' PAs revealed that 30 PAs (78.95% of the total) were strongly sustainable, eight (21.05%) were weakly sustainable, and none unsustainable. The results revealed that there was a positive correlation between several factors and PA-LS, including the density of the road network within a 1 km buffer of the PAs and the economic income and employment rate within a 5 km buffer of the PAs. Conversely, there was a negative correlation between one factor and PA-LS, its the distance between PAs and the urban center. Other factors, such as the category, area, classification of PAs, SHDI (ecological land), ED, LPI (forest) of PAs, and population density and residents' health within a 5 km buffer of the PAs, were unrelated to PA-LS.Conclusions This study established a PA-LS evaluation framework and its correlation factor analytical framework, which significantly contributes to enhancing the value cognition of PAs and enriching landscape-sustainability evaluation methods. Furthermore, the study provides valuable support and serves as a reference for the conservation and management of PAs in Beijing and similar metropolitan cities.