圖書典藏及影音數位平台

台東由北往南自利嘉溪、知本溪、文里溪至太麻里溪河口鄰近海岸，因受河口輸砂及海岸漂砂影響，於98年莫拉克風災後，造成河口及海岸地形明顯變化，為瞭解河口輸砂量及海岸漂砂，對鄰近海岸地形造成之影響及其變化趨勢，故擬針對上述河口及海域近岸地區進行進一步之調查與分析。另一方面，經濟部為推動臺灣深層海水產業之發展，交由本署負責於臺東縣太麻里鄉知本溪南岸興建「深層海水低溫利用及多目標技術研發模廠」，該模廠自知本溪南岸布放一條直徑50公分、取水深度700公尺之深層海水取水管，設計每日最大取水量為12,000噸，其於101年5月間因故發生取水困難，經水下影像檢視及海底地形測量結果發現，取水管布放路徑上水深400~700公尺皆約有6~8公尺之淤積，為降低模廠未來穩定供水之風險，對於其鄰近海域深層海底地形與其變化趨勢及海底底質情況亦有持續追蹤調查分析之需要。因此，為瞭解該海域輸砂、漂砂、地形變化與海底底質等整體交互作用之情況，以作為擬訂適當之河口及海岸防護措施，並提供模廠後續布設深層海水取水管路徑評估工作之參考，爰擬委託國內具有相關經驗之廠商（以下簡稱建置廠商）辦理本計畫。為確保現場調查能如期如質完成相關工作項目，將另案甄選現場調查監審辦理廠商（以下簡稱監審廠商），協助辦理各工作項目之進度控管及品質檢核作業。

In this study , we use geophysical survey method to identify marine Environment Investigation and Evaluation for Coastal Processes near Zhiben River thus analysis to recommend suitable laying area for deep sea water pipeline. According survey result and historical data ,the seabed topography were controlled by geology structure , high erosion rate caused by high fluvial Sediment output from river. The terrigenous sediment across survey area to Southern Longitudinal Trough is the mostly transport behavior.While either direct or indirect sediment source from river goes through-in deep water, thus depositing and filling among the ocean ridges. Slumping and other bed slope endogenic are the key features of steep slope movement. Results on sidescan sonar and seismic interpretation showed that between Chi-Pen and Li-Jia river, mostly, the plan area subfloor deposit, which most likely are to be seen as deep-sea furrow. More intensely, the drainage map shows that potential paths of submarine turbidity current extending down to 700 meter water depth, forming U shape gullies. Extensively, according to former research and the measurement that have done in this research the bottom velocity is mostly less than 0.2 m/s. All of this point out that intermittently happened turbidity current causes the pipeline maul-function. Therefore, it shows how unstable the seabed environment is. To summarize all the default cases that has shown, the suggestion is made to locate another safer area for the pipeline among the ocean ridges. The investigation duration lasted only 10 months that it is evidently not sufficient to reveal the long term morphodynamics characteristics. In order to construct a more reliable pipeline, it is suggested to continue carrying out the field survey and advanced site investigation. In additions, the planning and design work associated with the implementation techniques have to be studied and reviewed thoroughly.