桃園灌區為台灣重要的農業生產區域之一，其灌溉系統主要仰賴石門水庫水源及河水堰取水外，尚有埤塘供水系統，可做調度配水運用，本研究針對桃園大圳第二支線作為農業灌溉之研究區域，利用研究區域內之雨量站所測資料及灌區水文、地文與灌溉資料做為模式輸入資料之來源，配合系統動力模式模擬桃園灌區於一期作之運作情形，計算滲漏水量及灌區內水量變化等資料，進而得到灌區內A、B、C三個區域之迴歸水量，加入影響降雨型態之條件機率，模擬氣候變遷情形下未來降雨的分布形式，探討對農業用水之影響性分析，並改變系統總進水量及操作方式，以評估對作物生長之影響。Taoyuan irrigation area is one of the most important agriculture areas in Taiwan. The irrigation supply system operation of Taoyuan channel depends on Shihmen reservoir, river wire and ponds system. To analysis the return flow of agriculture irrigation flow under different irrigation operation, the second feeder of Taoyuan canal in northern Taiwan was chosen as study area. In this study, the rainfall station data, hydrology, land factor and irrigation operation function data was used as input data source of Vensim. The first-season, total 120 days which was from March 3rd to Jun 30th, was chosen as the analytic time. The simulation procedure calculated water balance day by day in each irrigation area from upstream to downstream. Compared with the simulation of Vensim, the water lack volume, water level difference and rainfall cases were used to calculate the return flow in each A, B, C subarea. The influence of rainfall pattern probability was used to simulate the future rainfall distribution under climate change. Change total water supply of system and operation rule to analysis the influence of agriculture supply and crop growth. 研究期間：9904 ~ 9912
