碩士 / 國立臺灣海洋大學 / 環境生物與漁業科學學系 / 97 / Abstract
The mean trophic level (MTL) and the fishing-inbalance (FiB) index were estimated by the landings in Taichung and Hualien fisheries association during 1999-2008. The results of this study were summarized as follows:
1. Due to the coastal waters of Taichung located in the continental shelf ecosystem. Therefore, the main fishing species were demersal, reef-associated, and invertebrates. Based on the landings data showed that these three species were increasing year by year whereas the pelagic and benthopelagic species were decreasing. According to the CTL analysis showed that the pelagic species were decreasing continuously while the invertebrates were increasing year by year.
2. While, Hualien were located near in the Kuroshio ecosystem. Then, the main fishing species was pelagic species, and the ratio of landings of this species was increasing in recent years.
3. The MTL and CTL showed that the proportion of pelagic species landings of Taichung was decreasing in 2001, in the meantime the invertebrates were increasing; and the average rate of descending of MTL was higher than worldwide average value. Even the MTL of Hualien area was trending up year by year, but its landings had reduced 60% in the last 10 years.
4. Due to the fisheries development and utilization, the trend of FiB in Taichung and Hualien showed that they were belonged to utilizing type downwards, it illustrated that the ecological resource and structure had been influenced seriously. Moreover, it also proved that the Taichung coastal fishery resource as unbalanced, and FDMFW (Fishing down marine food webs) appeared in Hualien since 2006.
Keywords: Trophic level (TL), Fishing-in-balance (FiB) index, Species group, Coastal waters of Taichung, Coastal waters of Hualien
| Identifer | oai:union.ndltd.org:TW/097NTOU5451036 |
| Date | January 2009 |
| Creators | Shih-Hao Chang, 張世豪 |
| Contributors | Cheng-Hsin Liao, 廖正信 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 91 |
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