The Measuring Experiment of Irrigation Water for Spreading Varieties of Rice Plant in Chuncheon Area

춘천지역의 장려수도품종의 용수량 측정시험

This Study was carried out at the experimental Plot of Kang-Weon Province, Institute of Agriculture experiment, to find out Irrigation Water requirement and suitable calculating formula of evapotranspiration on Spreading Varieties of rice plant such as Seul Oak, Bokkwang and Teaback in Chuncheon Area. The evapotranspiration, infiltration, and consumptive use of water were measured by Micro Lysimeter for four years from '86yr. Also, yield of rice was investigated during same period. With the Kc Value taken from experimental value, evapotranspiration was calculated by methods of Blaney & criddle, Penman, Hargreaves and Thornthwaite by Computer using meteorological data in Chuncheon Area for twenty one yrs from '66yr to '86yr. All analyses were conducted based on average value of experiment for four years and the results are summarized as follows : 1) The yield by varieties through this experiment showed 1.06 times in Seul Oak, 1.94 times in Bokkwang and 1.89 times in Teaback more than Standard Yield. 2) The consumptive use of water including infiltration were 1.068.4mm in Seul Oak, 1,102. 6mm in Bokkwang and 1,195.6mm in Teaback 3) The evapotranspiration by Actual measurement presented 520.lmm in Seul Oak, 540.lmm in Bokkwang and 598.4mm in Teaback 4)The ratio of evapotranspiration and infiltration over Panevaporation showed 1.2 to 1.4. 5) The irrigation water reguirement by water balance were shown to be irrigated more than 584 mm / yr in average during 21 years from '66yr to '86yr for all Varieties and those for loyr frequency 693 mm in Seul Oak, 712 mm in Bokkwang and 728 mm in Teaback respectively. 6) Crop Coefficient (Ke Value) of the tested rice plant during the period were shown as Table 10. 7) Penman Method was the formula the most close to experiment Value among four different methods of Blaney & Griddle Penman, Hargreaves, and Thornthwaite.