不同土壤水分条件下北方稻田耗水规律研究

采用田测法研究不同土壤水分条件下稻田需水规律．试验采用淹灌、湿润灌和间歇灌3种灌水处理．结果表明，在整个生育期内由田测法测得的淹灌、湿润灌和间歇灌3种处理的蒸散量分别为889．1、635．9和775．9mm．蒸散速率分别为6．9、4．9和6．0mm·d^-1．与淹灌处理相比．湿润灌和间歇灌处理分别节水28．5％和12．7％．在充分供水的情况下，由Penman法计算的潜在蒸散值分别比田测法小29．30％．淹灌、湿润灌和间歇灌3种处理的生物产量分别为16438．22、15887．94和15757．88kg·hm^-2．经济产量分别为8014．01、7828．91和7853．93kg·hm^-2．统计分析结果表明．3种处理间的产量差别不显著．淹灌、湿润灌和间歇灌3种处理的水分利用效率(WUE)分别为9．01、12．31和10．12kg·hm^-2·mm^-1．淹灌的WUE分别比湿润灌和间歇灌减少26．8％和11．0％．对比分析结果表明．湿润灌的节水效果最好．

Water requirement of paddy field under different soil water conditions

Field experiment with three irrigation treatments, i.e., continuous flooding irrigation (CSF), moisture condition irrigation (MTC), and intermittent irrigation (IT) were installed to study the water requirement of paddy fields. The results showed that in field experiment, the evapotranspiration(ET) was 889.1, 635.9 and 775.9 mm, and the evapotranspiration rate was 6.9, 4.9 and 6.0 mm.d-1 for CSF, MTC and IT, respectively during the entire growing season. MTC and IT were less than CSF by 28.5 and 12.7%. Under sufficient water supply, the evapotranspiration calculation by Penman formula was less than that from field experiment by 29.3%, during stages from returning green to milk. The biomass was 16438.22, 15887.94 and 15757.88 kg.hm-2, and the grain yield was 8014.01, 7828.91 and 7853.93 kg.hm-2 for CSF, MTC and IT, respectively. No significant differences were found among three treatments. The water use efficiency (WUE) was 9.01, 12.31 and 10.12 kg.hm-2.mm-1 for CSF, MTC and IT, respectively. The WUE of MTC and IT were higher than that of CSF by 26.8 and 11.0%, showing that MTC was a comparatively water-saving irrigation treatment.