碩士 / 國立中興大學 / 生命科學系所 / 100 / Due to few studies on the spatial-temporal variation of epiphytes in tropical seagrass beds, and few study areas with many seagrass species, this study chose the seagrass beds in Dongsha Marine National Park which was the first marine park in Taiwan since 2007, as the study area, aiming to understand the spatial-temporal variation of epiphytic assemblages growing on seagrass leaves, and the differences between epiphytes growing on different seagrass species, and also try to explore the influence of main environmental factors on the epiphytes. This study selected 5 sites around Dongsha Island; seagrass beds at north (N), south (S), and west (W) coasts, and also inside (8a) and outside (8b) the inner lagoon, respectively. The study was conducted bimonthly from December, 2009 to October, 2010. The results showed that biomass and species number of the epiphytes had a significant interaction between month and site. Biomass of the epiphytes showed higher in winter and lower in summer, and epiphytes at the shallow sites W, 8a and 8b had lower biomass. The regression analysis showed that biomass of the epiphytes was negatively correlated to temperature and extinction coefficient (K value); species number of the epiphytes increased through the months. Although species number of the epiphytes was positively correlated to temperature, it could be simply in the process of succession. The regression analysis also showed that species number of the epiphytes was positively correlated to water depth and NO2- + NO3-, indicating that the epiphytic assemblages were stably increased in deep water, and NO2- + NO3- might be the reason why the species number of Cyanobacteria increased. Biomass and species number of the epiphytes also showed significant differences among seagrass species. To reduce the interation of sites, we checked the epiphytic assemblages separately by site, and found that at site N biomass of the epiphytes growing on Cymodocea serrulata were higher than that on C. rotundata, and at site W that on Thalassia hemprichii were lower than that on C. rotundata, and at each site biomass of the epiphytes growing on T. hemprichii was often the fewest because of the smooth leaf surface. The species numbers of epiphytes were different among seagrasses at sites N, S, and W. When standardized into species number of epiphytes per seagrass leaf area, species number of epiphytes showed significant differences among sites: it was higher on Syringodium isoetifolium than other seagrass species at sites N and S; it was higher on Halodule uninervis at sites S, 8a and 8b; it was higher on Halophila ovalis at site W. Such differences might be affected by seagrass age, surface area of the substrate and the edge effect. Species composition of the epiphytic assemblages showed a seasonal shift among months, and there were different algal genera limited in different sites. According to PERMANOVA analysis, species composition of the epiphytes had a significant interaction between months and different seagrass species. When comparing the species composition of epiphytic assemblages at each site by month, the differences among seagrass species can be shown more easily. Examining the differences of the epiphytes among sites was considered as a larger-scale study, which may have difficulty to identify substrate type as an important factor. Thus, only when comparing the differences of the biomass, species number or species composition of epiphytes within the site, can the differences among substrates become conspicuous. This study focused on spatial and temporal variation of the epiphytes at Dongsha seagrass beds in a tropical monsoon climate, and also comparing their differences among 6 different seagrass hosts to provide a prelimimary understanding on how different seagrass species affect the epiphytes.
| Identifer | oai:union.ndltd.org:TW/100NCHU5105015 |
| Date | January 2012 |
| Creators | Hui-Yuan Chang, 鄭惠元 |
| Contributors | Shu-Chuan Hsiao, 蕭淑娟 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 146 |
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