Summary: | 碩士 === 逢甲大學 === 土地管理學系 === 88 === At September 21 1999 AM 1:47, away from Sun Moon Lake west about 12.5 kilometer occured magnitude 7.3(ML) earthquake, caused midland’s heavy casualties and property loss, and resulted in Taosling Jue-Lei Mountain a huge collapse to block Qing-Shui stream coming into being a landslide-dammed lake (New Tasoling Pool). Before the solution of whether New Tasoling Pool still retain have not each a final conclusion, how to proceed medium or long-term related renovated measures, and reach water and soil resource sustained use is the most important topic in present. But watershed renovating always faced with different manage objective conflict or trade-off, and traditional single objective decision method can not satisfy both sides of objectives even with choice information; But finite resource and multiple criteria decision making (MCDM) method can provide a satisfy solution for both sides of objectives.
Therefore, this study use GIS(Geographic Information Systems) and RS(Remote Sensing) techniques to assist extracting related spatial information for New Tasoling Pool watershed, and integrated MCDM PROMETHEE method to proceed spatial priority assessment analyze, and to provide a consultation reference. This study achieved some conclusions as following:
1.This study followed related literatures and reference of New Tasoling Pool watershed current situation to frame renovate objectives as “slow down water and soil disaster”; ”protect resident’s life and property”; “natural resource preserve”. Based on this account, this study used expert questionnaire to filtrate and confirm three categories totally sixteen types resulted criterion as factor “natural environment” includes landuse/landcover; soil erosion; geology; gradient; preserve area; secure forest; factor ”life and property” includes population; building(area); school; transportation; recreation facilities; social activity center; military and police facilities; factor “local personalities” includes historic place; religionary building and tourism resource potential factors.
2.This study selected two scholar/expert to assume as decision maker, and use their preference function and thresholds to proceed further analyze. Results showed that top 10 order of watershed management priority by each decision maker has little difference; while from estimative results, it showed each subwatershed which represent renovate priority an insignificant difference based on two combination of preference function and threshold values.
3.In one decision maker as an example, the study rise three categories weighting ratio respectively to proceed sensitivity analysis. A case of “natural environment” criterion, when weighting ratio being promote, the order tendency will substitute by subwatershed that has large bare collapse area; steep terrain and wide ecological preserve area gradually; As regard for “life and property”; “local personalities” criterion has the same situation; in other words, if subwatershed own that criteria constituents much more, the sort will be promote. Thus it can be seen, weighting ratio in this study has showed some interference with results, but not an absolute effect.
Key Words: landslide-dammed lake、multiple criteria decision making (MCDM)、Geographic Information Systems、921 earthquake.
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