圖書典藏及影音數位平台

透過歷年健檢指標數據與保育治理成果的彙整，進行滾動式檢討，以提供治理成效評估及未來規劃參考。本計畫透過函詢各執行單位，彙整其實施成果與執行計畫，並依滾動式檢討原則，根據前一年度成果及健檢指標數據，適時修訂次年度執行目標。後續所有資料將統一上傳至經濟部水利署「水庫集水區保育實施計畫填報系統」，完成線上填報作業。為釐清石門水庫集水區入庫砂量時空變化與主要輸砂機制，本研究整合雨量、流量、崩塌地、土地利用與水砂觀測資料，建立輸砂率定曲線與 SWAT 模式模擬架構，以估算 105-112 年石門水庫集水區之入庫砂量與坡面、河道輸砂特性。依霞雲站實測資料迴歸分析，建立流量–輸砂率定關係式 Qs=4.07698×〖10〗^(-5) Q^1.702（R^2=0.714），據此推估，105–112 年間集水區平均年輸砂量約 83.2 萬立方公尺，若考慮懸移質與推移質比例約 7 : 3，總入庫砂量約為 118.92 萬立方公尺/年，此數值低於長期統計之年平均169.3萬立方公尺。至於過去常引用之353萬立方公尺數值，係於特定資料與假設條件下之推估結果，與現行長期統計基準不同。整體而言，顯示近年集水區整治及清淤措施已有效抑制入庫泥砂。坡面與崩塌地輸砂量經土砂傳輸比（SDR = 0.306）折算後，年平均約 10.6 萬立方公尺，約占入庫砂量之 10%；其餘主要來源為河道沖蝕，年均約 108.32 萬立方公尺。高流量年份（110–111 年）河道沖蝕量顯著上升，與年降雨量及暴雨事件呈正相關。

Through the compilation of historical watershed health-check indicators and conservation governance outcomes, a rolling review mechanism was applied to evaluate governance effectiveness and support future planning. This project collected implementation results and action plans from relevant agencies through official correspondence. Based on the rolling review principle, the implementation targets for the following year were adjusted according to the previous year’s achievements and health-check indicator data. All information will be uploaded to the Reservoir Watershed Conservation Implementation Plan Reporting System of the Water Resources Agency under the Ministry of Economic Affairs to complete the online reporting process. To clarify the spatiotemporal variation of sediment inflow and major sediment transport mechanisms in the watershed of Shimen Reservoir, this study integrated rainfall, discharge, landslide inventory, land-use data, and sediment monitoring records. A sediment rating curve and a simulation framework based on the Soil and Water Assessment Tool (SWAT) model were established to estimate reservoir sediment inflow and analyze hillslope and channel sediment transport characteristics for 2016–2023 (ROC years 105–112). Based on regression analysis of observed data at Xiayun Hydrological Station, the discharge–sediment relationship was derived as: Qs = 4.07698 × 10⁻⁵ Q¹·⁷⁰² (R² = 0.714). The estimated average annual sediment yield of the watershed during 2016–2023 is approximately 0.832 million m³. Considering a suspended load to bed load ratio of 7:3, the total annual sediment inflow to the reservoir is about 1.19 million m³, which is lower than the long-term average of 1.693 million m³. The previously cited value of 3.53 million m³ was derived under specific datasets and assumptions and therefore differs from the current long-term statistical reference. Overall, the results suggest that recent watershed management and dredging measures have effectively reduced sediment inflow to the reservoir. After applying the Sediment Delivery Ratio (SDR = 0.306), the estimated annual sediment contribution from hillslopes and landslide areas is about 0.106 million m³ (approximately 10% of the total). The remaining 0.108 million m³ mainly originates from channel erosion. Higher channel erosion was observed in high-flow years (2021–2022; ROC years 110–111), showing a positive correlation with annual rainfall and extreme rainfall events.