卵砾石河床型态演变对物理性栖地影响之实例研究-中华水土保持学会.PDF

48 中華水土保持學報, 42 (1): 48-56 (20 11) Jour nal of Chinese Soil and Water Conservation, 42 (1):48-56 (2011) 卵礫石河床型態演變對物理性棲地影響之實例研究 [1] [2]* [2] 劉建榮 許少華 潘俊弘 摘 要 本文以筏子溪卵礫石河床條件觀察河床型態演變對物理棲地之影響，並重新定義適 合筏子溪之物理棲地型態參數範圍：分別為淺瀨 (水深30 cm 、流速30 cm/sec) ，緩流(水 深60 cm 、流速30 cm/sec) ，深流(水深30 cm 、流速30 cm/sec) ，深潭(水深60 cm 、 流速30 cm/sec) 。透過航照圖結合現場量測分析出筏子溪橋下游為交互沙洲的河床型態，並 找出其從上游至下游之物理棲地規律為淺瀨 (Riffle) 、深流 (Run) 、深潭 (Pool)與緩流 (Guild) ，以交互沙洲代表長度L 來量化物理棲地可得淺瀨為0.1~0.2 L 、深流為0.2~0.3 L 、 深潭為0.3~0.4 L 、緩流為0.2~0.3 L 。 關鍵詞：筏子溪、物理棲地、交互沙洲 。 A Case Study of River Morphodynamics and Impacts on Habitat in a Gravel-Bed Stream Chien-Jung Liu[1] Shaohua-Marko Hsu[2]* Jun-Hung Pan[2] ABSTRACT This research was focused on the physical habitat of Fa-Zih River and observed the changes after the morphological development in the condition of gravel-bed. Furthermore, the form of physical habitat in Fa-Zih River is re-defined: Riffle (depth30 cm, velocity30 cm/sec), Guild (depth30 cm, velocity30 cm/sec), Run (depth30 cm, velocity30 cm/sec), Pool (depth60 cm, velocity30 cm/sec). Based on aerial photos and river-bed measurement, the morphological type of the downstream Fa-Zih River was categorized as alternating bars. If parameter L is defined as the length of a single sand bar, the type of physical habitat can be identified as Riffle (length is about 0.1~0.2 L), Run (length is about 0.2~0.3 L), Pool (length is about 0.3~0.4 L), and Guild (length is about 0.2~0.3L) from upstream to downstream.