曾文水庫位於嘉義縣、台南縣與高雄縣交接處，為嘉義縣大埔鄉曾文溪主流上游，總容量達7 億立方公尺，為全省容量最大之水庫。近年來由於經濟活動大量開發水庫上游集水區，產生之污染物質，導致表土沖蝕、逕流增加，造成水庫淤積、蓄水弁鄐暾謅峇纁w水質惡化成優養狀態；並影響防洪弁鄐峔悀纀鄐O，並減少水庫壽命。為維護水庫水質，必須先從曾文水庫上游水源保育做起。本研究利用地理資訊系統建立曾文水庫17個子集水區、三個縣及六個鄉等分區之水文條件、地文條件及土地利用及污染分佈等評估指標，並應用在企業規劃管理決策分析中相當實用的VIKOR決策分析方法，透過分析各分區水文條件、地文條件及土地利用及污染分佈等因子，來推估應優先實施土地利用優先管制的區域，以建立各子集水區應行之土地利用管制策略，使曾文水庫能充分發揮弁鉬P永續利用，實為水庫水質管理的重要目標。 Tseng-wen reservoir is located at the junction of Chiayi County, Tainan County and Kaohsiung County and in the upstream of Tseng-wen River. The reservoir is the largest reservoir in Taiwan with total capacity of 700 million cubic meters. Recently, excessive human activities in a watershed of the upstream brings water pollution and increases domestic consumption, and furthermore results in topsoil erosion, runoff increasing and domestic wastewater dramatically increasing. Moreover, it also promotes the reservoir silted up and eutrophication.
Watershed protection and management relies on conservation of water resource in the upstream. This study utilizes geographic information system (GIS) to separate the watershed into 17 sub-watersheds and several regions for simulating; moreover, applies VIKOR method to determine the effect factors, such as hydrologic or physiographic conditions, of impact variations in the downstream, so as to determine the priority strategies on the restraint of land-use activities in the watershed.
