濕周－流量法應用於推估河川生態基流量之研究

Estimation of Ecological Reference Flow by Wetted Perimeter-Discharge Method

陳樹群(Su-Chin Chen) ； 王信凱(Hsin-Kai Wang)

《中華水土保持學報》 31卷3期 (2000/09) Pp. 193-203

https://doi.org/10.29417/JCSWC.200009_31(3).0003

摘要

本研究主要目的有二：一爲探討使用濕周－流量法推估河川生態基流量時，橫斷面形狀所造成的影響；二爲以目測法、斜率法及曲率法推求濕周－流量曲線中之轉折點，進而求得生態基流量，並以烏溪下游段爲例進行分析。研究後發現，爲排除不必要的斷面形狀影響，應選取濕周－流量曲線中第一個濕周劇烈變化處所對應的流量作爲演算時之上限。而轉折點之推求，應以目測法爲優先考慮；無法以目測法判斷時，則使用斜率法及曲率法推求之。研究顯示烏溪下游斷面所推求出之生態基流量，若只考慮河川橫斷面形狀，爲6.0〜120.0cms；若加上水生生物生存之水理條件及河川污染問題之考量，則爲39.45〜87.0cms。

關鍵字

濕周-流量法 ； 生態基流量

並列摘要

This study aims: (1) to analyze the influence caused by the channel cross-section geometric type when using wetted perimeter-discharge method to determine the ecological reference flow; and (2) to analyze the determination of the break point on the wetted perimeter-discharge curve by eye, slope and curvature method. According to the analysis of Wusi Creek, it is reasonable to choose the flow that corresponds to the first break point to be the upper limit of the ecological reference flow. The breakpoint should be determined by first eye. Otherwise, it should be determined by the slope method and the curvature method. The ecological reference flow was 6.0~120.0 cms if only the channel cross-section geometric type was considered; but was 39.45~87.0 cms if the aquatic life and river pollution in Wusi Creek were taken into account.

並列關鍵字

wetted perimeter-discharge method ； ecological reference flow