以長時間河川低流統計資料特徵化臺灣南部流域消退特性之研究

Characterization of Recession Behavior in River Basins in Southern Taiwan using the Long-Term Low Flow of Statistical Streamflow Data

高于婷(Yu-Ting Kao) ； 葉信富(Hsin-Fu Yeh) ； 李振誥(Cheng-Haw Lee)

《中華水土保持學報》 46卷2期 (2015/06) Pp. 114-122

https://doi.org/10.29417/JCSWC.201506_46(2).0006

摘要

臺灣地形起伏變化高與降雨量空間分布差異很大，以致造成水資源分佈不均勻，近年來受氣候變遷影響，區域性乾濕季變化更加明顯，雨量集中在夏季，尤其以臺灣南部地區乾濕季差異最大，乾季面臨嚴重缺水問題。在枯水期，地下水為補注河川的重要來源，因此瞭解地下水與河川流量之間的儲存-排出關係日益重要。本研究採用低流分析之消退曲線建立河川流量與地下水之間儲存-排出關係，該方法的優點僅需取得流量資料。在低流分析中排除降雨與蒸發散的影響，僅與集水區內所儲存的水有關聯，因此消退曲線參數化後可以對集水區表現其消退特性。本研究以臺灣南部流域為例，以長時間連續河川資料統計集水區特徵，比較Vogel and Kroll（1992）與Brutsaert（2008）兩種模式對臺灣南部流域消退特性表現之差異性，進而量化臺灣南部地下水儲存量，結果顯示東港溪流域的潮州測站最低地下水儲存量為顯著下降趨勢，應要實施相關防範措施。

關鍵字

河川流量 ； 低流 ； 消退曲線 ； 地下水儲存量

並列摘要

The uneven distribution of water resources in Taiwan is due to severe topography change and unevenly distributed rainfall. Recently, climate change has resulted more apparent wet and dry seasons in the region. Because water deficit problems are more severe in the dry season, which is in the low flow period, groundwater is the main source of recharging streams. Thus, knowing the relationship between groundwater and stream drainage-storage is becoming increasingly important. This study establishes a recession curve to show the relationship between streamflow and groundwater storage-drainage. The advantage of low flow analysis is that it only requires streamflow data. We exclude precipitation and evapotranspiration in low flow analysis that is only related to river basin water. Thus, the recession curve is characterized to display basin drainage behavior. In this study, we use southern Taiwan streamflow data covering a long-term period to analyze basin characteristics. The differences of drainage behaviors are compared using the Vogel & Kroll (1992) and Brutsaert (2008) methods. Furthermore, the groundwater storage in the south of Taiwan is quantified. The results show that Chaozhou station in the Donggang River Basin has a significantly decreasing trend. Chaozhou station should implement precautionary measures.

並列關鍵字

Streamflow ； low flow ； recession curve ； storage