REEF DEGRADATION AND CORAL BIODIVERSITY IN INDONESIA - EFFECTS OF LAND-BASED POLLUTION, DESTRUCTIVE FISHING PRACTICES AND CHANGES OVER TIME

Species-area curves calculated from line-intercept transect surveys on 15 reefs in three regions of Indonesia allow estimation of the relati ve decrease in within-habitat coral species diversity associated with different types of reef degradation. Reefs subject to land-based pollu tion (sewage, sedimentation, and/or industrial pollution) show 30-50% reduced diversity at 3 m , and 40-60% reduced diversity at 10 m depth relative to unpolluted comparison reefs in each region. Bombed or anch or damaged reefs are ca 50% less diverse in shallow water (3 m depth) than are undamaged reefs in the same region, but at 10 m depth the rel ative decrease is only 10%, Comparison reefs in the Java Sea are ca 20 % less diverse than their counterparts in Ambon, Maluku, The results, compared with a previous survey in the Spermonde Archipelago found a 2 5% decrease in generic diversity of corals on two reefs resampled afte r 15 years, The decreased diversity on reefs subject to land-based pol lution implies a dramatic, rapid decrease in Indonesian reef-based fis heries resources. (C) 1998 Elsevier Science Ltd. All rights reserved.