翡翠水庫上游集水區水質趨勢分析與迴歸模式建立

本研究藉由長期之水質監測資料與流量資料，結合地理資訊系統針對多尺度範圍內土地利用與平均坡度之分析，探討影響翡翠水庫上游集水區水質趨勢變化的因素與建立預測水質之迴歸模式。水質趨勢分析是以無母數方法中之季節性趨勢分析(seasonal Kendall test)，檢定翡翠水庫集水區之DO、SS、TP、NH3-N、BOD、大腸桿菌群以及pH值共7項水質參數是否具有遞增或遞減之趨勢存在。為探討1996至2005年間北宜高速公路開發工程對集水區水質可能造成之衝擊，以2006年為基準年，探討水質趨勢變化之差異。結果顯示北宜高速公路之施工會造成北勢溪下游測站與魚逮魚堀溪上測站之SS與pH值顯著上升，且各測站之DO濃度皆顯著下降。除原觀測值之趨勢分析外，本研究亦以流量校正趨勢探討近期之水質變異情形，結合多尺度土地利用與水質變異之迴歸分析，探討水質與土地利用之相關性。流量校正趨勢能進一步指出當地水質之變化是否為人為污染所造成，而從2006~2009年流量校正趨勢結果，得知魚逮魚堀溪與北勢溪下游之TP濃度有顯著上升之趨勢，NH3-N濃度於魚逮魚堀溪下游亦為顯著上升，表示此地區之河岸兩側高密度茶園與農業耕作可能為造成當地水體之營養鹽濃度上升之主要原因。最後探討多尺度土地利用與水質變異之相關性。結果顯示多尺度土地利用分析所建構之水質推估模式，能有效解釋土地利用之區域性差異，可能造成大腸桿菌群濃度與BOD濃度之變異情形。以距測站之500公尺局部範圍內之土地利用分析結果建構之BOD濃度推估模式具有最佳之解釋能力(R2=0.967)。而平均坡度因子之加入，能有效提升多尺度土地利用建構之水質推估模式之解釋能力，尤以300公尺之河岸範圍尺度下之土地利用與平均坡度所建構之TP濃度推估模式有最佳之解釋能力(R2=0.823)。而坡度因子亦能提升距測站1000公尺之局部範圍尺度之土地利用建構之大腸桿菌群濃度推估模式之解釋能力(R2=0.954)。本研究針對集水區水質之趨勢探討結合多尺度土地利用與平均坡度建構之水質推估模式，能有效評估集水區內之長期工程開發與土地利用情形對於集水區水質所造成之衝擊，透過水質之時序資料分析與多尺度土地利用，以及平均坡度所建構之水質推估模式，能針對水質受人為開發所造成之衝擊做整體性評估，並對後續集水區之土地利用規劃及管理給予一參考指標。

關鍵字

翡翠水庫上游集水區；水質趨勢分析；水質迴歸模式

並列摘要

The aim of this study was to evaluate the effects of the development of the upper watershed of the Feitsui Reservoir on the water quality trends using non-parametric seasonal Kendall test. Seven water quality parameters including dissolved oxygen (DO), suspended solids (SS), total phosphorus (TP), ammonia nitrogen (NH3-N), biochemical oxygen demand (BOD), total coliform (TC), and pH value were studied. This study also developed regression models to estimate water quality; the variables consideres include land slope, landuse, and sites of the areas. Construction of Taipei-Ilan Freeway started in 1996 and finished in 2005. A case study was conducted to evaluate potential effects of the construction activities on the quality of nearby water bodies. The results indicated that the SS and pH values of the nearby rivers increased; on the other hand, the DO value decreased.The changes could be attributed to the conctruction activities of the freeway. It was reported that flow-adjusted concentrations can reflect anthropogenic effects, so this study also compared the flow-adjusted concentrations with observed values. The results indicate that the flow-adjusted concentrations of TP increased downstream of Bei-Shih and Tai-yu-cheuh streams. The flow-adjusted concentrations of NH3-N also increased downstream of Tai-yu-cheuh stream. The tea-agriculture might be the contributing factor for the increases. The results of the regression models show that urban land use coupled with land slope have noticeable impact on total coliform and total phosphorus concentrations. The BOD concentrations depended more heavily on landuses. This study provides a useful tool to estimate the effects of urban developemant on quality trend of receiving waters. Regression models developed could be used to evaluate the effects of land use, land slope, and sites of watershed on water quality.

並列關鍵字

Upper watershed of the Feitsui Reservoir ； water quality trends ； water quality estimated regression model

參考文獻

陳俊銘，(2006)，”運用地理資訊系統於翡翠水庫集水區非點源污染潛勢地區分析”，國立台灣大學生物環境系統工程學研究所碩士論文。

謝玉萍、王志遠、習良孝，(2009)，”坪林行控中心專用道開放之環保減輕對測及執行成效”。中興工程季刊，104，77-84。

黃正龍，(2006)，”暴雨時期河川污染物磷負荷量推估方法之研究”，台灣大學土木工程學研究所碩士論文。

Allan, J.D., Erickson, D.L., and Fay, J., (1997). The Influence of catchment land use on stream integrity across multiple spatial scales. Freshwater Biology, 37, 149-161.

Antonopoulos, V.Z., Papamichail, D.M., and Mitsiou, K.A., (2001), Statistical and trend analysis of water quality and quantity data for the Strymon River in Greece. Hydrology & Earth System Sciences, 5, 679-692.

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翡翠水庫上游集水區水質趨勢分析與迴歸模式建立

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