溪流整治工程為水庫集水區治理相當重要的一環，隨著人們對生態環境的重視，量化人為介入對水庫集水區溪流生態環境之影響性亦顯得重要。本研究主要探討土砂產量對河川集水區溪流物理棲地之變化，及採用人為工程對物理棲地之影響；本研究選定石門水庫集水區為分析對象，擬定調查作業程序，完成石門水庫集水區之十八條支流河川之現場調查，並分析彙整其調查成果。在本研究的分析過程中，本研究先針對18條河川進行河相五層分類分析，探討該河川河相特性及集水區內可能引發之土砂運移問題；而在土砂量估算上，本研究以1999年集集地震、2001年桃芝颱風及2004年艾利颱風為主要土砂災害事件，並估算屢次災害事件後之土砂總產量(包括崩塌量及土壤沖蝕量)，並利用現地勘查瞭解目前土砂在河道中堆積情況及對物理棲地造成影響。本研究採用河川物理棲地評估指標進一步瞭解目前18條河川物理棲地現況，主要探討泥沙堆積、地形、人為影響、植生復育及水流多樣性等，並以雷達圖表示目前河川物理棲地現況，比較自然棲地與人為工程介入棲地對棲地復育之影響，並提出未來復育方針及建議。此溪流物理棲地評估方法可量化工程對棲地之影響結果，對於石門水庫集水區之溪流物理棲地而言，人為干擾較少、流量越大、水流多樣性越好的集水區，溪流原始狀況佳。River training work is a considerably important link to reservoir watershed management. With people's focus on ecological environment, quantifying the influence of personal interference on the ecological environment of river in reservoir watershed shows significant accordingly. The study focuses the discussion of the influences of river physical habitats caused by sediment yield in the watershed and river engineering. This study chose Shihmen Reservoir watershed as analysis object. It drafted investigation operation procedures, completing on-site investigation of eighteen branches of Shihmen Reservoir watershed, collecting and analyzing the investigation results.The study analyze the river morphology characteristic and possible sediment transport questions of eighteen rivers by river morphology five-level classication method. The total sediment yield, including landslide and soil erosion, after Chichi earthquake in 1999, Typhoon Toraji in 2001 and Typhoon Aere in 2004 were estimated in the study. Field survey was proceeded to understand the sediment transport condition in eighteen watershed.The study uses the river physical habitat assessment index to analyze the physical habitat restoration condition of eighteen river watershed. The river physical habitat assessment index includes the sediment transport, topograph, river engineering, vegetation restoration and the diversity of flow. The radar graph which is calculated and built from the assessment by river physical habitat assessment index is used to show the river physical habitat condition and compare the difference between the natural river habitat and artificial river habitat. The study addresses the restoration direction of each river watershed and field survey point. This method quantifying the influence of artifical interference on habitat
