和平溪口海岸地形變遷之研究

Study on the Topographical Change of Heping River Estuary

王星宇(Hsing-Yu Wang) ； 方惠民(Hui-Ming Fang) ； 蕭松山(Sung-Shan Hsiao)

《海洋工程學刊》 18卷3期 (2018/11) Pp. 205-225

摘要

影響河口海岸沈積環境特性的自然因素在不同時間與空間尺度下，各因子以不同程度影響著地形變化，惟其位置的特殊性與營力的多樣性，導致於河口海岸地區進行諸多研究之困難。本研究以海陸互動的觀點，針對海岸地形變遷數值模式進行地形與水動力機制引起的海岸漂沙交互作用，以及將隨潮汐水位變化造成的海陸互動機制整合於海岸地形變遷數值模式。本研究將河川輸沙與海岸漂沙分為漂砂底床載、懸浮砂及懸浮泥等，整合於海岸地形變遷模式中計算非均質底床及地形交互作用。以和平溪口附近海域為研究標的，模擬不同入流條件下所形塑之河口海岸地形特徵。由數值時間作用一年之結果與實測地形資料比較顯示，地形變化明顯處為和平溪口、和平港南防波堤、及南側養灘區，而和平溪河口附近水深-10~-40m 處呈侵淤互現，鄰近和平港港口處呈現淤積與實測結果吻合。

關鍵字

海岸地形變遷 ； 非均質底床 ； 河口海岸

並列摘要

The natural factors affecting the sedimentary environment characteristics of the estuary coast affect the topographic changes to varying degrees at different time and space scales. However, the particularity of its location and the diversity of its battalions have led to difficulties in conducting many studies in the coastal areas of the estuary. Based on the interaction between sea and land, this study conducts the dynamic interaction of coastal sediment transport caused by topography and hydrodynamic mechanism for the numerical model of coastal topographical change, and integrates the sea-land interaction mechanism caused by the change of tide level. In this study, river and coastal sediment transport are divided into suspended load and bed load, which are integrated into the coastal topographic transition mode to calculate the heterogeneous porous seabed and topographic interaction. This study uses the sea area near Heping river estuary as the research target to simulate the topography under different inflow conditions. The comparison between the results of the numerical time and the measured topographic data shows that the topographic changes are obviously in Heping river estuary, the south breakwater of Hoping Port, and the south side beach area.

並列關鍵字

Coastal topographical change ； Heterogeneous porous seabed ； Estuary