ABSTRACT
130In recent decades conservation of biodiversity has been high on the international agenda, following the establishment of the Convention on Biological Diversity in 1992 (United Nations 1992a, b). International agreements have called for conservation efforts that prioritize areas particularly rich in biodiversity or in other ways unique. Parallel to the political debate, a scientific debate on how to prioritize conservation efforts is ongoing. This chapter documents the diversity and distribution patterns of the rattans on Borneo, assesses their conservation status and identifies priority areas for rattan conservation. It is the first study of any plant group on Borneo using a specialized analytical database, WORLDMAP. A total of 5045 rattan records were gathered from eight different herbaria and through fieldwork. Two thirds of the 144 rattan taxa on Borneo are endemic. At least 18.8% of the rattans on Borneo and at least 23.5% of the endemics are threatened. Three rattans are critically endangered. Patterns in taxon richness indicate that the northern and north-western areas harbour more taxa than those in the south and the east, and patterns in range-size rarity indicate that endemism hotspots are found in the south-western Sarawak, Brunei and the central parts of Sabah. The protection of rattans provided by the current set of reserves is no better than a random selection of areas. It is shown that a complementarity method is the most efficient in identifying priority areas for rattan conservation on Borneo. Using complementarity, 23 of the 1087 grid cells in WORLDMAP are required to represent all taxa at least once and, where possible, in a grid cell with more than 10% natural vegetation, 26 grid cells are required.
