| Summary: | 碩士 === 國立臺灣大學 === 海洋研究所 === 94 === Coral reefs are found in all waters around Taiwan except in the sandy areas on the west coast. Approximately 300 scleractinian species are found in Taiwan and its offshore islets. The occurrence and relative abundance of 130 species or species groups in coral communities at 16 sites from 6 reef regions in Taiwan were surveyed by transect method. The result of cluster and MDS analysis shows that coral communities in eastern and southern Taiwan possess similar species compositions, whereas those of north coast and northeastern Taiwan form another group. The other three sites with distinct species compositions were Dofujia of Yilan County, Yinggeshi of northeastern coast, and Yeyou at Lanyu. Using the same set of scleractinian distribution data and data from previous studies, we modeled the spatial relationship of corals with Genetic Algorithm for Rule-set Prediction (GARP), a method for learning the spatial relationships of organisms and its environment, and used it to predict the influences of climate change on coral communities in Taiwan. The results show that the distribution pattern of scleractinian corals in Taiwan is congruent with that of sea surface temperature and ocean currents, suggesting their importance in shaping regional coral communities in Taiwan. Other factors such as wave exposure and sedimentation are in addition important in shaping local coral communities. Under the impact of climate change and projected rise in sea surface temperature, the spatial distribution of corals is likely to expand and the species richness in most areas would increase in the short-term prediction. However, the spatial distribution of corals would contract with species richness in most areas decreasing dramatically in the long-term predictions. Unbalanced changes of coral communities can also be envisaged from the model predictions.
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