IMPACT OF CLIMATE AND LAND-USE CHANGE ON TREE DISTRIBUTIONS IN SOUTHEAST ASIA

Abstract

The tropical forests of Southeast Asia (SEA) are exceptionally biodiverse but also highly threatened. Land use change devastate forests at unprecedented rates while climate change threatens to drive massive extinctions. There is thus an urgent need to model and understand the impact of these global changes on species ranges. In that regard, species distribution models (SDMs) offer a data-driven approach towards evaluating global change impacts on tree distributions. However, SDMs suffer methodological gaps, particularly when modelling species with poor data quality and for subsequent interpretation of complex spatial datasets. Here, I first assessed the effects of global changes on dipterocarp species in the Philippines and identified gaps in the current protected area network. Second, I elucidated problems with modelling species with poor data quality and provided a strategy to overcome them. Third, I developed an approach for clustering spatially associated species to better summarise and visualise complex spatial datasets. Finally, I investigated the impact of global changes on Southeast Asia tree distributions from 1960 to 2090. My findings advance current methodologies in SDM, but more importantly, serve to inform policymaking and conservation planning while improving our understanding of the SEA biodiversity crisis.