节水稻基农田作物轮作与灌溉模式需水规律研究

Study of water-demand regulations and water use efficiencies for water-saving rice cultivation patterns

采取田间试验方法,研究了南方丘陵典型季节性干旱区节水稻基农田作物轮作与灌溉模式的需水规律和稻田水分利用率。结果表明,节水稻基农田作物轮茬与灌溉模式通过对水稻和油菜等作物产生的生长调控作用和补偿生效应,使植株蒸腾量、棵间蒸发量及稻田渗漏量大幅降低,各阶段的腾发量、需水强度和需水模系均发生显著变化,形成了稻基农田作物轮茬与灌溉模式新的需水规律。与常规双季模式相比,节水灌溉双季稻模式、水旱轮作双季稻模式、稻油轮作模式的需水强度分别减少了0.76、1.15、0.71 mm/d,渗漏强度分别减少了0.12、0.16、0.19mm/d,水分利用率提高了30.14%、47.95%、17.81%。

The study of water-demand regulations and water use efficiencies （WUE） under conditions of different water-saving rice cultivation patterns were carried out through the field-scale experiments. The results show that the evapotranspiration of rice or rape reduced by a wide margin, and the water requirement and requirement intensity and coefficient at every stage change greatly with the growth regulation function and the compensation effect on crop of water-saving rice cultivation patterns. Thus, the new water requirement rules of water-saving rice cultivation patterns are formed. Compared with the conventional double cropping rice puttern, the water requirement intensities of the water-saving irrigation pattern of the double cropping rice （WSIPDCR）, the flood-drought cultivation pattern of double cropping rice（FDCPDCR）, and the water-saving rice cultivation pattern of rice and rape rotation （WSRCPRRR） decrease by 0.76 mm/d, 1.15 mm/d and 0.71 mm/d, respectively; The leakage intensities of WSIPDCE, FDCPDCR, and WSRCPRRR decrease by 0.12 mm/d, 0.16 mm/d and 0.19 mm/d, respecitively.The WUE of WSIPDC, FDCPDCR, and WSRCPRRR increase by 30.14%, 47.95 % and 17.81% respectively.