水收支平衡應用於水田灌溉用水消耗特性之評估

Estimation on Consumptive Characteristic of Irrigation Water for Paddy Fields Using Water Balance Theorem

陳豐文(Feng-Wen Chen) ； 劉振宇(Chen-Wuing Liu)

《農業工程學報》 59卷1期 (2013/03) Pp. 77-98

https://doi.org/10.29974/JTAE.201303_59(1).0006

摘要

本文以台中葫蘆墩圳灌區為研究區域，以2001-2005年各項水文及用水記錄為資料來源，應用水收支平衡原理推估水田長期灌溉條件下各項用水來源及耗水參數的變化及特性；結果顯示研究區域之兩期作水田的田間需水量分別為1,593 （mm/期作•ha）及1,381（mm/期作•ha）；若考量輸水損失之引水量提高為2,570（mm/期作•ha）及 2,227（mm/期作•ha）。統計灌溉歷程產生之明迴歸水及暗迴歸水比例為 1.85：1（一期作）及 3.13：1（二期作）；兩期作之有效雨量及其利用率分別為293 mm（63%）及242mm（41%），顯示雨量利用對於水田一期作補助灌溉之重要性。水收支平衡原理分析大區域水田灌區之水分消耗特性顯示長期灌溉歷程中，水田系統水量的消耗途徑，以補注地下水量為主，約48.80%，其說明水田灌溉對於地下水資源涵養之重要貢獻，其次產生20.45%迴歸水量，為水資源再利用之潛勢量，作物需水量為19.92%，有效雨量僅10.83%。

關鍵字

水田灌溉 ； 水平衡 ； 迴歸水 ； 有效雨量 ； 作物需水量

並列摘要

In the article, the water balance theorem was used for evaluating the consumptive characteristic of irrigation water on paddy fields, which in the condition of crop irrigated during the long-term period. The irrigation area of Huludum main canal was selected as an research region, and the each water records and hydrologic data in 2001-2005 was used to analyze. The results show that water requirement (WR) of paddy fields in the first and second crop periods were 1,593 and 1,381 (mm/crop period•ha) respectively. With considering the conveyance loss, the irrigation water requirement was intake from rivers were raised to 2,570 and 2,227 (mm/crop period•ha) in the first and second crop periods.The 5 years average of effective rainfall was conducted to analyzed as 293 and 242 mm in the first and second crop periods, and the usage ratio were respectively showed as 63% and 41%. The result revel the significance that effective rainfall played a subsidiary for irrigation in the first crop period. The study used the water balance theorem was conducted to analyze evaluate the consumptive characteristic of irrigation water in a large scale paddy region, and the results show the main consumption of water is to recharge the groundwater in paddy field system, and the the ratio was 48.80%. Return flow, evapotranspiration and effective rainfall were the subsequent in order, and the contributions were respectively showed as 20.45%, 19.92%, and 10.83%. Return flow was consists of visible return flow and invisible return flow, and the ratio between them in the first crop period and second crop period were respectively 1.85:1, and 3.13:1.

並列關鍵字

Irrigation on paddy field ； Water balance ； Return flow ； Effective rainfall ； Crop requirement