A Study on Tsaoling Landslide Area Landform change by Comparing the Map from 1930s till 1998s

草嶺地區為台灣有名之大崩塌地，歷史上曾發生過四次大規模之崩塌，尤其1999年9月21日發生集集大地震時中部山區有多處崩塌。其中尤以雲林縣古坑鄉草嶺村附近之堀畓沓山所發生崩山之規模最大，其大量崩落土石阻斷了清水溪之水流，並在崩落區之上游形成堰塞湖（草嶺潭）。由於此堰塞湖可能會因某種因素而潰壩，並造成下游地區嚴重之土石災害，故曾造成ㄧ陣恐慌。倘能對其早期至今之地形變化進行了解，必能有益於對其現況之處理及未來再發生崩塌時處理決策之訂定。 本研究蒐集了國內外相關之研究資料，並以1930年繪製(1904年開始測量)之台灣堡圖及於1998年與1999年拍攝之航空像片，分別製作成數值高程模型(DEM)。接著進行自1930年至1999年的地形變遷分析，期能增加早期地形變化特性之了解，必能有助於對崩塌區地形變遷較完整之認知。經過平面校正後發現台灣堡圖中未變區地形之走向大致與1998年經正射之影像相符，且1998年較1930年的崩塌區增加三處，應為1941年與1979年兩次崩塌所造成。另外，河道之左岸向右岸偏移約360m，亦即河道明顯向右岸順向坡之基腳侵蝕，使岩層下端受到掘鑿作用失去支撐而形成自由端，經雨水之浸潤與地震之搖震而失去平衡，以致造成堀畓山持續發生崩塌至倒交山。由於兩個時期產生誤差之原因不少，必須經過日據時代平面及高程測量之誤差檢定與校正等步驟，方可做更精確的量化分析。Tsaoling Landslide Area is celebrated for avalanche in Taiwan. There have had four times of serious collapses in history. Above all, the Chi-Chi Earthquake that occurred at September the 21-th of 1999, caused an especially number of collapse. At the Chi-Chi Earthquakes, the scale was great in Kuh-lum Mountain, in Gukeng Village of Yun-lin County. There were very much slid down earth mass and stone blocked on Ching-Shui Stream and formed a Tsaoling Lake. Because the barrier levee of the lake may breach due to breaking down for some causes and occur calamity and panic at the lower stream area. If we can investigate the landform change clearly it will help us to make a good policy for treating the mass of collapse. This study has gathered international paper about collapse, and gathered the ancient map of 1930 year then to build the DEM for analyzing the change of landform of Tsaoling Landslide Area during 1930 to 1999 for expecting we can understand the landform characteristic of nowadays landform and original landform. After plane-proof reading, we discovered that the unchanged area of the former map is similar to the landform of 1998. The three sites of newly collapsed of 1988 after 1930 was inferred from the collapsed at 1941 and 1979. The location of river moved approximately by 360m from left bank to right bank, and the bottom of the consequent slope of the rock stratum in right bank was eroded. It has formed a free end of the rock stratum in Kuh-lum Mountain and after the water eroding the rock stratum was unbalanced and then caused landslide for raining and earthquake. Owing to some errors for the two different times, plane and elevation check and adjustment must be introduced to perform a precise analysis.中文摘要 I ABSTRACT II 目 錄 III 表 目 錄 V 圖 目 錄 VI 壹、前言 1 貳、前人研究 2 一、 草嶺地區的自然條件及歷史 3 (一) 草嶺地區地質條件 3 (二) 草嶺地區崩塌原因 4 (三) 草嶺地區崩塌歷史 5 二、 日據時代台灣堡圖之由來 7 (一) 1899年地籍調查 7 (二) 三角測量 7 (三) 地形調查 8 (四) 三角點 8 三、 座標系統之演進 10 (一) 大地座標 10 (二) 平面座標系統 10 四、 數值地形模型於地形分析之理論及應用 13 (一) 數值模型於地形分析之理論 13 (二) 數值模型於地形分析之應用 14 参、研究構想與方法 17 一、 研究流程 17 二、 研究方法 18 三、 DEM資料產生方式 18 (一) 由航空像片製作 19 (二) 由數化等高線製作： 23 四、 平面改正 28 五、 地形分析 31 (一) 高程變化 31 (二) 崩崖變化 31 肆、結果分析與討論 32 一、 數值地形模型之成果 32 二、 日據時代與現代地形之比較 38 (一) 地形分析 38 (二) 地形變化之比較 45 (三) 變遷探討： 47 伍、結論與建議 53 一、 結論 53 二、 建議 55 參考文獻 5

The Warning System of Slopeland Disaster by Using the Tank Model

台灣土石流警戒模式主要以降雨量做為警戒指標，為提升與強化現行土石流警戒預報模式，本研究導入日本之筒狀模式進行警戒指標研究，透過筒狀模式之土壤雨量指數建立「土砂災害發生危險基準線(C.L線)」。本研究步驟：首先建立適用台灣坡地地區筒狀模式參數，並由筒狀模式建立台灣地區山坡地集水區洪峰流量估算方法及流程，提供山坡地集水區內資料不足或無流量測站時，分析參考。再者將土壤雨量指數應用於現行土石流警戒預警模式，以建立台灣地區之土砂災害發生危險基準線(C.L線)，使國內土石流警戒預報發布精度提升，有效降低土石流災害之傷亡。最後架構ArcView客製化介面提供後續研究者參採。The current debris flow warning model in Taiwan is established on the basis of the rainfall warning index. The study tries to establishes "the critical line of the occurrence of debris flow" by using the Soil Water Index (SWI) in the tank model which was used widely in Japan. The procedure of the study is as follows. The study estimates the suitable coefficient in the tank model in Taiwan and the estimating method and procedures of the peak discharge in the mountainous watersheds in Taiwan. The estimating result can be a reference for the mountainous watersheds with insufficient data. The study uses the SWI to calculate the critical line of the occurrence of debris flow in the current debris flow warning model in Taiwan. The critical line of the occurrence of debris flow can increase the accuracy of the debris flow warning and decrease the casualties in the debris flow disasters in the future. Furthermore, the study also establishes customized user extension software in Arcview System for further application

Evolution of Urban Development Investigated by Multiphase Orthophoto-A Case Study from Green-Stream in Taichung

本研究提出以建物、交通與農業等設施面積做為人為開發指標，並以公園、森林、其他綠帶面積作為綠覆指標，以此兩種指標評估都市土地利用之變遷。另以歷年航空影像資料分析綠川變遷及其周圍地區之都市發展、河道生態環境及河道流路等演變情形。此外，本研究將試區分為5個區段，並由都市變遷指標分布探討5個區段之都市變遷情形。結果顯示，台中市綠川區域自1981年開始快速發展，尤其高工路至樹王一路所在第四區段發展最為快速，該區域於1990年開始建物面積大幅增加，農業及森林等綠帶面積大幅減小。而中興大學所處之第三區段由於實施過河道截彎取直工程，故蜿蜒指數由原先1.44降低至1.22。另結果顯示由都市變遷指標分布可以分析區內土地使用面積變化而歸納都市變遷情形，本研究並將都市開發程度分為低開發區、農村區、高低密度都市區等四種等級，作為探討都市及鄉村之變遷依據，並探討其都市緊湊度所獲得結果，可提供相關決策者及研究者參考。This study proposes that using these two indicators to assess urban development; the first one is human development indicator which include areas of buildings, transport and farmland; and the second one is green cover indicator which include areas of parks, forests, and other greenbelts. Then, we used multiphase orthophoto of Green-Stream in Taichung to analyze evolution of urban development, river environment and flow channel. Furthermore, we divides area of Green-Stream into five zones, and we uses the two indicators of urban development to investigate evolution in urban development of five zones. The results show that the area around Green-Stream of Taichung rapidly developed since 1981, particularly in the fourth zone, which was near the Gaogong road to Shuwang 1st road. The buildings area of the fourth zone began significantly increasing since 1990, and therefore the greenbelt area, which includes farmland and forests, significantly decreased. Furthermore, Green-Stream was straightened in the third zone, which was near the National Chung Hsing University, and thus the meandering index was decreased from 1.44 to 1.22 in 1990. In addition, the results also show that two indictors classify urban development situation, and the change of urban development degree was divided into four development levels, which include low-develop zone, countryside zone, low-density urban zone and high-density urban zone. This result can be the basis for the possible discussion of urban development and related researches

高屏溪流域崩塌地之地形特徵分析

An analysis method for landslide topographic characteristic, considering the factors such as landslide size, average slope, location and geologic condition, was used to draw landslide scale and slope statistical chart. The landslides caused by the typhoons in 2008 and 2009 in Kaoping River Watershed were investigated and then analyzed. The landslide ratios were 1.36% and 7.92% in slate area in 2008 and 2009, respectively. The highest degree of increase in landslide ratio showed the landslide probability in slate area rose obviously because of the heavy rainfall during Typhoon Morakot. The analysis results of landslide topographic characteristic showed landslide average slopes were lowest, 39.8˚ and 34.8˚ in 2008 and 2009, and the probability of the whole slope landslides was highest in hard sandstone and shale area. Additionally, the landslide average slopes were highest, 46.8˚ and 41.2˚ in 2008 and 2009 in Tananao schis area, and there was no whole slope landslide in 2008 and 2009 in quartzose sandstone area and Tananao schis Area.本研究考量崩塌地規模、平均坡度、發生區位及地質條件等因子，提出一套分析崩塌地地形特徵之 方法，藉此建立崩塌規模與坡度統計圖，並以高屏溪流域 2008 年及 2009 年之颱風事件所引發上游崩塌災害 案例進行分析。板岩區在 2008 年與 2009 年之崩塌比分別為 1.36%及 7.92%，提高程度最高，顯示莫拉克颱風 強降雨誘發下板岩區崩塌機率明顯增加。由崩塌地之地形特徵分析成果顯示：堅硬砂岩與頁岩區之崩塌地平 均坡度最低，2008 年與 2009 年分別為 39.8˚及 34.8˚，最容易出現全坡面崩塌情形；大南澳片岩區之崩塌地平 均坡度最高，2008 年與 2009 年分別為 46.8˚及 41.2˚；石英砂岩區、大南澳片岩區 2008 年與 2009 年皆未產生 全坡面崩塌情形