The Establishment and Discuss of the Vulnerability Assessment for Flood Risk

Source: ICHE Conference Archive - https://mdi-de.baw.de/icheArchiv

斜面災害地域ハザードマッピングに基づく脆弱性と曝災の評価

本稿では自然災害におけるリスク，脆弱性，曝災，ハザートマップについて，概説している。この研究では住民，地域，地方自治体、国など階層ごとに脆弱性を評価した。また，地域のリスクアセスメントにより，ハザートマッピンクと曝災の関係を筆者らは確認した。さらに，曝災を評価するため，ハザードマッピンクでロジスティックと判別分析手法を用いて，流域の斜面崩壊の確率を評価した。最後に，空中写真でこれらの手法を検証することにより，危険度評価に適切なモデルを提案した。This paper describes the relationships between exposure, hazard mapping, and vulnerability analysis, and represents the initial hazard mapping results of the exposure analysis. Based on different scales, vulnerability can be divided into five layers. Several connections of these five layers, the levels of vulnerability are defined, as vulnerability of the individual, village, country, and central government. Landslide susceptibility is calculated to evaluate exposure based on hazard mapping methods, including logistic regression and discriminant analysis. Finally, the results made from the discriminant analysis are considered acceptable upon comparing these with the aerial photographs.本稿では自然災害におけるリスク，脆弱性，曝災，ハザートマップについて，概説している。この研究では住民，地域，地方自治体、国など階層ごとに脆弱性を評価した。また，地域のリスクアセスメントにより，ハザートマッピンクと曝災の関係を筆者らは確認した。さらに，曝災を評価するため，ハザードマッピンクでロジスティックと判別分析手法を用いて，流域の斜面崩壊の確率を評価した。最後に，空中写真でこれらの手法を検証することにより，危険度評価に適切なモデルを提案した。This paper describes the relationships between exposure, hazard mapping, and vulnerability analysis, and represents the initial hazard mapping results of the exposure analysis. Based on different scales, vulnerability can be divided into five layers. Several connections of these five layers, the levels of vulnerability are defined, as vulnerability of the individual, village, country, and central government. Landslide susceptibility is calculated to evaluate exposure based on hazard mapping methods, including logistic regression and discriminant analysis. Finally, the results made from the discriminant analysis are considered acceptable upon comparing these with the aerial photographs

土砂災害地域防災計画の検討と防災構造物に基づく脆弱性の評価

本稿では土砂災害における防災計画，脆弱性について，概説し，評価している。この研究では台湾の1999年から2006までの防災計画に内容と施行方向を筆者らは述べました。また，この内容により，欠点を検討しながら、提案を示した。さらに，防災工程の効果を評価するため、DTMとFLO-2Dで自然条件と沈砂池を設置してる条件と土石流に脅してる地域をシミュレーションし，結果について議論しました。最後に，空中写真でモデルの結果を検証することにより，災害軽減ための工程構造物の脆弱性に適切なモデルを提案した。This paper describes a vulnerability assessment method related to the disaster risk reduction plan and debris flow disaster. Based on the government disaster mitigation strategies and historical data for debris flow in Taiwan, several insufficient of the disaster risk reduction plan are referred. Several suggested strategies are pointed out thereby. On the other hand, numerical simulations are done to the torrents with potential dangerous via Flo-2D software under the natural condition case, the detention basin case, and the levee case. It is clarified the efficiency of the detention basin case and the levee case when considering of different factors. Finally, conclusions are made according to the results.本稿では土砂災害における防災計画，脆弱性について，概説し，評価している。この研究では台湾の1999年から2006までの防災計画に内容と施行方向を筆者らは述べました。また，この内容により，欠点を検討しながら、提案を示した。さらに，防災工程の効果を評価するため、DTMとFLO-2Dで自然条件と沈砂池を設置してる条件と土石流に脅してる地域をシミュレーションし，結果について議論しました。最後に，空中写真でモデルの結果を検証することにより，災害軽減ための工程構造物の脆弱性に適切なモデルを提案した。This paper describes a vulnerability assessment method related to the disaster risk reduction plan and debris flow disaster. Based on the government disaster mitigation strategies and historical data for debris flow in Taiwan, several insufficient of the disaster risk reduction plan are referred. Several suggested strategies are pointed out thereby. On the other hand, numerical simulations are done to the torrents with potential dangerous via Flo-2D software under the natural condition case, the detention basin case, and the levee case. It is clarified the efficiency of the detention basin case and the levee case when considering of different factors. Finally, conclusions are made according to the results

南投縣仁愛鄉崩塌特性分析及崩塌風險模式建構

The study developed landslide susceptibility and risk models based on landslide inventory collected after 2009 Typhoon Morakot in Renai Twonship, Nantou County. Approximately 57.0% of landslide cases induced by Typhoon Morakot in Renai Township were located in downslope locations, whereas 20.5% were located in upslope locations. The study created landslide susceptibility models by using logistic regression and the weight of evidence method. The accuracy of these two landslide models were 74.47% and 61.92%, respectively. The logistic regression– based landslide susceptibility model can predict most shallow landslide cases; however, it cannot predict groundwaterinduced landslides. Considering the landslide susceptibility and cost of buildings and roads, landslide loss caused by 24-h accumulated rainfall with the return period of 50, 100, and 200 years were estimated to be 1.18 × 109 , 2.40 × 109, and 3.87 × 109 dollars, respectively.本研究以南投縣仁愛鄉在 2009 年莫拉克颱風後崩塌目錄，建構仁愛鄉內之崩塌潛勢評估模式及 風險模式。仁愛鄉在 2009 年莫拉克颱風後之崩塌案例，有 57.0%位於下邊坡及 20.5%位於上邊坡，且崩塌規 模以小規模崩塌為主。崩塌潛勢評估模式建構分別以邏輯式迴歸法及證據權重法進行，兩種方法之正確率分 別為 74.47%及 61.92%，因此選定邏輯式迴歸法建構之崩塌潛勢評估模式，經現場比對後，該模式能預測出多 數淺層崩塌，但難以適用於地下水誘發的地滑型崩塌。最後將崩塌潛勢結果結合研究區域內之建物與道路成 本，套疊不同頻率年 24 小時累積降雨，獲得仁愛鄉在 50 年、100 年及 200 年 24 小時累積降雨事件下，可能 產生的損失風險值分別為 11.8 億、24.0 億及 38.7 億元

氣候變遷資料應用於土石流衝擊與土方量之推估

Totally 40 debris flow torrents in the Zousui river basin were selected for numerical simulation to clarify sediment impact due to climate change. Rainfall data from the climate scenario representative concentration pathway (RCP) 8.5, generated through dynamic downscaling and bias correction, were used to simulate discharge through Hec-HMS and debris flow impacts through Flo-2D, as well as the variation in impact from the end of 20th century to the end of 21st century. The results indicate that total sediment impact by debris flow exhibited an increasing trend of approximately 11%. Thus, rainfall variation affects debris flow. This manifests not only among sub-catchments, but also in the same sub-catchment, in that numerous sediments from torrents import to the main flow and affect the downstream area.為了解氣候變遷對土砂高潛勢區域影響，篩選濁水溪流域內 40 條潛勢溪流，以氣候變遷暖化情境 RCP8.5 經動力降尺度和偏差校正後所產製的降雨資料，由 Hec-HMS 模擬流量後，再以 Flo-2D 模擬與分析從 20 世紀末至 21 世紀末土石流衝擊及變化。結果顯示，21 世紀末之土砂量為增加的趨勢，幅度約 11%。氣候 變遷模式結果顯示，降雨型態改變將對土石流發生有所衝擊，其差異除了表現於不同子集水區之外，在同區 域內亦將因多數潛勢溪流匯入大量土砂，對中下游造成影響