| Summary: | 碩士 === 國立成功大學 === 水利及海洋工程學系 === 104 === There are 247 goby species in Taiwan, and 12 of them are recognized as endangered freshwater species. Therefore in this study, at the beginning we placed four types of artificial habitats of all different materials and shapes, at downstream spots of Watergate No.1, Wugoushui Village and Wufu Bridge. Later, through sampling eggs of red-spotted goby in different places such as artificial habitat, natural habitat and measurements on environmental factors and hyporheic water, with statistical analysis tools we could tell target species’ preference for bottom material and environmental factors while laying eggs, in order to further see whether artificial habitats benefit target species or not. In the study, through principal component analysis, we found the critical controllable factors for gobies to choose their artificial habitats or natural rocks. Spots with eggs mainly tend to be regions with high level of dissolved oxygen, and this shows that, in the study, during the period from placing habitats to sampling, the natural rocks in sampling station still could not be completely replaced. Since the time of placing artificial habitat was not long enough, so artificial habitats in regions with low level of dissolved oxygen could not completely adapt to the natural environment. Moreover, through relation between total areas of where gobies can lay eggs in artificial habitats or natural rocks where are with eggs detected or can be laid eggs, we can see when available habitats are less, artificial habitats adopted are considerably more. When available habitats are more, there is no significant difference between the numbers of natural rocks and artificial habitats adopted.
|
|---|
