Conservation of Borneo biodiversity: do small lowland parks have a role, or are big inland sanctuaries sufficient? Brunei as an example

Borneo, the World’s fourth largest island, represents a continental mass sandwiched between volcanic arcs. Patterns of tree species richness, here proposed as proxy for overall biodiversity, and endemism within the island are described and interpreted with special reference to Dipterocarpaceae. Most of Borneo’s surface is sedimentary shales, mostly inland, and sandstones, mostly coastal, deposited in past epicontinental seas. The shales mainly support the regional West Malesian (Sundaland) tree flora, while the Neogene coastal hills, especially in the north-west, support the richest communities which are also richest in endemics. The forests of these hills, which include the richest tree communities in the Old World and are therefore of global significance, are accessible and critically endangered. Priorities for their future management are outlined.