乾季時期水庫農業用水放水量調配模式之研究

臺灣地區由於降雨時間分佈不均，乾季期間水庫儲存的有限水量，常不敷分配給各標的用水使用，致使缺水旱象頻傳，此種現象在南部地區尤其明顯。一般而言，水庫之供水標的，可分爲農業用水、工業用水及公共給水。由於農業用水之使用水量頗鉅，再加上農業用水對於缺水之容忍程度較富彈性，因此每逢旱象發生，水庫內尙存的有限水源，往往優先供應公共給水及工業用水，而將農業用水列爲次要的供應對象。因此爲了有效降低農作物因缺水而導致的收成損失，有必要研擬一套乾季時期水庫農業用水調配模式，以因應這種週期性的潛在缺水威脅。本文提出之乾季水庫農業用水調配模式，主要的研究內容包括兩部份：一爲水庫入流量之預估研究，另一爲水庫農業用水放水策略之研究。本文建議整體考量乾季期間之水量供需調配，使農業用水之總缺水量平均分配到各旬，以減緩缺水之負面衝擊。本文並以白河水庫作爲本模式驗證檢討之研究案例，驗證之結果顯示，本模式應用於水庫農業用水放水量之調配成效甚佳。

關鍵字

無資料

並列摘要

Because the rainfall distribution in Taiwan is very uneven, the water impounded in reservoir is often unable to meet the demand of various water uses for dry seasons. In recent years the drought occurs frequently especially in southern Taiwan. Generally the reservoir supplys water for agricultural use, industrial use and demotic use. Because the quantity of agricultural water is very huge and the tolerance of water deficit of agriculture is more flexible, the limit water remainning in reservoir during droughts is always firstly supplied to demotic and industrial uses while the agricultural release is placed in the secondary priority. In order to reduce the drought damages resulting from agricultural water deficit, it's necessary to study the allocation model of reservoir agricultural release to prevent the potential threat from water deficit. This paper proposes an allocation model of reservoir release for irrigation. The model comprises two main parts. The first part predicts the reservoir inflow. The second part studies the reservoir operation policies of agricultural water release. It considers the interactive reaction of water supply and user demand. The goal of the release policies is that the total deficit of agricultural water in terms of percentage shall be distributed evenly to ecah 10-day period and thus to reduce the adverse impacts of water deficit. The Pai-Ho reservoir in southern Taiwan is chosen as a case study to evaluate the pertinency and usefulness of the proposed model. The result shows that the allocation of reservoir release for agricultural water through the model operation is quite satisfactory.