Simulation and Evaluation on Necessary Irrigation Quantity of Water in Fields That Has Been Affected by Climate Change

―The case of turf fields in Hokuei-cho, Tottori Prefecture―

Abstract

We estimated the necessary irrigation quantity of water of the turf field by the simulation using a tank model to evaluate the influence that climate change gave to irrigation. The simulation intended for the past 41 years from 1979 through 2019. As a result, the necessary irrigation quantity of water was a tendency to meaningful increase, and the irrigation quantity of water was found to have risen 15% in 41 years. We performed a multiple regression analysis to assume necessary irrigation quantity of water as the objective variable, while the explanatory variable was meteorological conditions. Using a multiple regression type, we evaluated the influence that each meteorological elements gave for increase of the necessary irrigation quantity of water. As for the ratio of the increased factor of the necessary irrigation quantity of water, two of the temperature and the maximum consecutive dry weather days accounted for 81.1% of factors. In addition, the planning irrigation quantity of water was decided using past data, but it was shown that there is the possibility that the irrigation security degree decreases because necessary irrigation quantity of water increases as the progress of years.