921地震(1999年9月21日)發生至今(2021年)已20餘年，在震災初期中部山區崩塌裸露區位極為嚴重，而在無人為干擾之自然復育情形下，崩塌地變遷及其植生復育狀況，實有探討之必要性。本研究以南投縣國姓鄉之九九峰地區為樣區，以地震前後之SPOT衛星影像結合非監督性之SOM模式判釋樣區之崩塌區位，並以Kappa統計量評估判釋之準確性；再輔以植生指數及植生復育率，評估崩塌地變遷及其植生復育狀況，作為九九峰崩塌區位變遷及後續災害治理之參考。藉由本研究對九九峰震災地區之監測與評估，可瞭解該地區自然復育之環境永續議題。此外，藉由多期衛星影像長期評估該區921地震災害之生態復育情形，可瞭解大自然對921地震災後崩塌地之植物入侵復育能力。本研究萃取之崩塌地面積為865.22公頃，整體精確度為92.58%，Kappa值為0.8516，顯示SOM模式可萃取高精確度之崩塌地。而植生復育率計算及評估部份，由於該區在長達20餘年之自然植生復育，即使在期間遭受颱風豪雨之侵襲，裸露地表隨著植物之自然入侵已接近100%之植生復原，顯示大自然本身有極佳的植生復育能力。 It has been more than 20 years since the 921 earthquake (September 27, 1999). In the early stage of the earthquake, the collapse of exposed areas in the central mountainous region was extremely serious, and it is necessary to investigate the change of collapse location and vegetation recovery without human interference in natural recovery. In this study, SPOT satellite images before and after the earthquake combined with unsupervised Self-Organizing Map classification were used to determine the landslide location of the studied area. Through the monitoring and evaluation of the earthquake area in JouJou Peak, the environmental sustainability issues of natural restoration in the area can be discussed. In addition, the long-term assessment of the ecological restoration of the 921 earthquake disaster in the area through multi-temporal satellite images can provide an understanding of nature's ability to restore the vegetation of the landslide sites after the disaster. The area of the landslide sites extracted in this study was 865.22 hectares, with an overall accuracy of 92.58% and a kappa value of 0.8516, indicating that the SOM model can extract the landslides with high accuracy. As for the analysis of the vegetation recovery rate, the natural vegetation recovery of the area for more than 20 years, even though the area was attacked by typhoon and heavy rain, the surface of the land was nearly 100% vegetation recovery with the natural invasion of plants, indicating that nature itself has excellent vegetation recovery ability.
