하수처리수의 농업용수 재이용을 위한 관개수량 산정방법에 관한 연구

Abstract

The purpose of this study was to establish the estimation method of irrigation water amount for sewage treated water reuse for agricultural purpose. To calculate the irrigation water amount, we adopted Penman-Monteith for potential evapotranspiration estimation and applied crop coefficient andirrigation efficiency factor. We developed the irrigation water amount calculation program using C language in Xcode environment. The target districtfor calculation is having 259 ha of agricultural land located near the Jinyeong Clear Water Circulation Center in Hanrim-myeon, Gimhae city. Themeteorological data of the study area were obtained from Changwon weather station from 1986 to 2017. Calculated average and maximum of annualmean potential evapotranspiration were 2.72 mm/day and 6.22 mm/day, respectively. We used K-S (Kolmogorov-Smirnov) for goodness-of-fit test tofind optimal probability distribution of annual mean and maximum evapotranspiration. As a result, the normal distribution was selected for theappropriate distribution. The annual mean and maximum potential evapotranspiration for 10-year return period by applying normal distribution were 2.88mm/day and 6.76 mm/day, respectively. Assuming that the irrigation efficiency is 80%, the irrigation water requirement was calculated as 36.05 m3/day/ha and 84.45 m3/day/ha, respectively, when annual mean and maximum potential evapotranspiration were applied. The actual irrigation water amountcan be calculated by applying the crop coefficient and cropping days for the study area based on the developed irrigation water amount estimationprogram in this study.