隨著沿海地區、聚落、農工業等發展和人們對海岸資源需求量的增加,河口地區研究的重要性日益提高。河口地區受海洋潮汐及河川逕流的影響,具有河川和海洋水文互動的現象與特質,其河川水位及流量隨季節呈週期性變化,潮汐力是其主要作用機制,直接影響河川水位的上下起伏波動,造成河口地區水位變化甚大。 由於河口的重要性,加上近年來河口地區災害頻傳,管理與維護的工作日漸受到重視,在這之前必須先了解河口地區之物理特性及交際,如對河口地區進行水理演算等工作,才能對河口進行正確的管理及維護。在過去,河口之辨識有利用地形地貌或是利用水體中含鹽濃度來區分。河口水位是在進行水理計算時邊界條件及參數之設定當中佔有相當重要的一部分,這將直接影響計算完之結果。所以若能將河口地區分成受感潮河段及非感潮河段兩個部分,這將簡化變界設定時之困難。 因此本研究中以希伯特-黃轉換來分析淡水河河口範圍之水位變化,利用此方法研究出一個可以判斷河川水位站是否受潮汐影響的方法,以此方法進行河口範圍的界定。
As the coastal areas, settlements, agro-industries development and people's increasing demand on coastal resources, estuarine areas of growing importance. Estuarine areas by the ocean tide and river runoff, rivers and oceans with interactive hydrological phenomena and the characteristics of the river water level and flow changes periodically with the seasons, while tidal forces is the main mechanism, directly affect the river water level up and down slope action, causing a great change in estuarine water areas. As the importance of estuaries, estuarine areas in recent years with numerous reports of further damage, it should strengthen the management and maintenance, before that must be on the estuary area of water management such as flood routing calculation, in order to understand the physical characteristics of estuarine areas can be on the estuary to do the right management and maintenance of water management during the calculation, but the boundary conditions and parameter settings are important, and this will directly affect the calculation of complete results. So if the estuary is divided into subject areas and non-tidal reach of the two parts of tidal rivers, which will simplify the difficulty of changing community settings. The study by Hibbert - Huang transform to analyze the scope of the Tamsui River estuary water level changes, use this method to work out an can determine whether the river water level stations affected by the tidal method, this method of defining the scope of mouth.