Protected Areas' Wildland‐Urban Interfaces on Frontlines of Forest Loss and Reforestation

Abstract

Protected areas (PAs) are increasingly disturbed by expanding wildland‐urban interfaces (WUIs). However, the extent of WUIs within PAs and the mechanisms underlying forest dynamics within WUIs remain poorly understood, limiting reliable assessment of PA effectiveness. Here, we quantify WUI dynamics in global PAs and assess forest dynamics within and surrounding WUIs. We show WUIs in PAs nearly tripled between 1985 and 2020, driven largely (>85%) by encompassing pre‐existing WUIs into new PAs. Between 2000 and 2023, over half of forest loss (29.72 Mha) in global PAs occurred within WUIs and their 5 km surroundings, which is attributed to intensive human activities through non‐fire processes, for example, agriculture and logging, while fire‐induced forest loss increases with distance outside the WUIs. The results also reveal that in global PAs, over 50% of forest gain (5.54 Mha) during 2000–2020 and over 70% of reforestation potential (8.84 Mha) is concentrated within WUIs and their 5 km surroundings, underscoring the dual role of WUIs as both the frontlines of forest loss and the areas with the greatest potential for reforestation. These findings highlight the need to incorporate WUIs into future conservation planning to balance human development with biodiversity protection.