Actual condition of water utilization in upland irrigation zone: studies on design of upland water requirement (I)

摘要

The present study was performed to investigate the actual conditions of the water utilization at zone level in upland irrigation zone from the observations of variations of planted area of each crop, potential ET and daily amount of water utilization. The observations were carried out for many years in 4 zones of the Kantou area. The study-spot were in SH and HO zones of Mikatahara irrigation district in Shizuoka, MH zone of Hokusoutoubu irrigation district in Chiba,and MO zone of Fuefukigawa irrigation district in Yamanashi. In each irrigation district, more than ten years have been passed since the main upland irrigation facilities were constructed by the govenment supported project. The findings are as follows; 1) There is a positive correlation between the potential ET by using the Penman method and the daily amount of water utilization per planted area. 2) The maximum daily amount of water utilization is caused by supplemental water demand in summer. 3) Much daily amounts of water utilization except in summer are caused by water demand for cultivation management. 4) Frequent water utilizations throughout the year occur in the upland irrigation zone including greenhouse cultivation. 5) The maximum design amount of daily consumption of water is reasonable. 6) It is desirable to consider no-planted area to design upland water requirement.