New water consumption pattern of rice under water-saving irrigation

Abstract

Since 1982 tests of rice irrigation technique of controlled soil moisture content have been carried out at the Mairendian Testing Station of Hohai University and Jining Water Conservancy Bureau. The results prove that the water consumption (including ecological and physiological consumption) and output of rice vary considerably according to the different irrigation techniques used. In this paper, the water-saving effects are explained in terms of correlation between the varieties of ecological environment of rice growing and physiological indices such as soil moisture, soil air, soil temperature, leaf area index and stoma aperture etc., and rice root growth and a formation of an ideal colony. This irrigation technique makes watering quota most economical and efficient. The water consumption is reduced by 41% and only 46.8% of water are required for flooding irrigation. Rice yield increases by 15%. Not only are interplant evaporation and field seepage greatly reduced but also transpiration is greatly reduced under controlled irrigation. New water consumption pattern of rice growing is thus formed.