Loss and vulnerability of lowland forests in mainland Southeast Asia.

: Despite containing extraordinary levels of biodiversity, lowland ( 120,000sq.km. of forest (50% of forest present in 1998) was lost. Of the 14 lowland forest landscape patches, six lost >50% of their area. At the country scale, Cambodia suffered the greatest deforestation (>47,500sq.km). In 2018, only 18% of the lowlands were forested, and only 20% of these forests had some formal protection. Approximately 50% of the lowland forest inside protected areas (c. 11,000sq.km.) was also lost during the study period. Most lowland forest remaining is highly vulnerable, with eight landscape patches having more than 50% categorized as such. Our results add to a growing body of evidence that the presence of protected areas alone will not prevent further deforestation. We suggest that more collaborative conservation management strategies with local communities and conservation concessions specifically for lowland forests are urgently needed to prevent further destruction of these valuable habitats. Article impact statement: From 1998 to 2018, mainland Southeast Asia lost 50% of its lowland forest, including a 50% loss inside protected areas. This article is protected by copyright. All rights reserved.