Studies on the Effective Rainfall of Upland Irrigation Design Water Requirement

点击翻译按钮获取中文摘要

The amount of upland irrigation water requirement was necessary to reconsideration viewpoint of practice upland irrigation, in humid region like Japan.This study examines about relationships between upland irrigation water requirement and the effective rainfall, of the experimental farm and upland irrigation field.The results are summarized as follows :1. The irrigation effect was admitted at proper irrigation water quantity at the Atsugi Central Experimental farm. But it happened that over irrigation, by increase of precipitation at the drip irrigation test farm.2. The quantity of water use was dependent on kind of crops, season and effective rainfall. But amount of effective rainfall was little influenced for amount of upland irrigation water requirement.Because it was difficult to presume of precipitation and to control of water taken through intake facilities.3. The settlement method of this study was calculation of effective rainfall by take statistics, and the relationships of practice effective rainfall at the upland irrigation area from precipitation data. And the small portion of rainfall, which was considered ineffective at the planning time, is useful for increase of soil moisture and admitted for effective rainfall. And the drip irrigation system had been useful in saving water and increase of effective rainfall.4. If this study's methods are recommended in used, the reduction plan of irrigation water demand may be expected. Then it is possible to cultivation at the little water source rural.