過去溪流生態環境品質評估多以單指標評估為主，少有綜合性的評估，同時
由於不同評估指標其評估內涵之不同而有評估的差異。綜合性評估因併入多項指
標，具有較多元之解釋能力，但困難處為各指標彼此間之權重該如何估計訂定。
因此本研究旨在以結構方程模式 (Structural Equation Modeling) 來發展一種新的
複合式溪流評估模式各指標權重之估算。案例係以石門水庫自然旅遊地大漢溪主
支流八個測點為區域，自2003 年至2004 年8 季所進行之環境調查為資料，而使
用之模式因子包含河川污染指標 (RPI)、生物整合指標 (IBI)、定性棲地評價指
標 (CQHEI)、Hilsenhoff 科級生物指標 (FBI)、快速生物評估法III (RBP III)、藻
屬指數 (GI) 及腐水指數 (SI) 等七因子。由求得之權重代入複合式溪流評估模
式進行本區生態品質之評估，結果發現生態品質有地理分布上之差異。

Previous studies of eco-environmental quality assessment of streams have relied on single indicators. Few comprehensive assessments have been applied simultaneously. Different evaluation indicators owned their diverse variations thus,integrated assessment results with a number of indicators, have more explanatory capability. However, some difficulties occurred as to how to assess and estimate the weighting values of the indicators. This study aimed to use Structural Equation,Modeling (SEM) to develop a new Stream Integrity Assessment Model (SIAM) to combine indices’ weightings. In one case study, we conducted seasonal surveys at a
Tahan Stream tributary with eight sampling stations in the Shihmen Reservoir watershed, at eight different times from 2003 to 2004. We used environmental and/or eco logical factors including River Pollution Index (RPI), Index of Biotic Integrity (IBI), Qualitative Habitat Evaluation Index (CQHEI), Family-level Biotic Index (FBI), Rapid Bioassessment Protocol III (RBP III), Generic Index (GI), and Saprobity Index (SI). From the result of this SIAM for ecological quality assessment,
the variation of the geographical distribution of the ecological quality was detected.