为了研究膜下滴灌旱作水稻灌溉定额和施肥量对产量的影响。采用通用旋转组合设计试验方法,建立膜下滴灌旱作水稻水肥耦合模型。结果表明,在供试土壤膜下滴灌条件下,灌溉定额、氮、磷与水稻产量之间符合三元二次回归模型,其一次项、二次项及水氮交互项回归系数均达极显著水平,三因素的增产作用大小依次为:灌溉定额〉施氮量〉施磷量。采用此模型计算的预测产量与实际产量之间呈高度正相关(R^2=0.981),并可由此计算得出目标产量灌溉定额及其施肥量。经模型寻优,得出不同目标产量下的水、氮、磷最佳组合方案,通过2 a验证试验,验证产量与水分生产效率与模型优化组合目标产量和水分生产效率相吻合,此最优组合方案可以为膜下滴灌旱作水稻节水节肥、水肥一体化技术和高效栽培技术提供科学依据和理论支持。
Studies on how to improve the yield of rice, which are mostly affected by water and fertilizer, are receiving more and more attention. However, little is known about the coupling effect of irrigation and fertilizer on rice's yield and water production efficiency(WPE). This study aimed at investigating the relations of water and fertilizer with the yield of rice cultivated in aerobic soil with drip irrigation under plastic film. The field experiments were conducted to establish yield model of water and fertilizer coupling of rice. Two groups of tests were set up including a preliminary test conducted in Yinchuan Xixia in 2012, and verification test conducted in Yinchuan Xixia in 2013 and Yinchuan Helan in 2014.The annual average rainfalls were 208, 260 and 300 mm for the three year. By quadratic current rotary combination method, 3 treatments of irrigation quota, N and P2O5 fertilizers with 5 levels for each were designed. Each plot was 25 m in length and 1.4 m in width, and plots were separated by 50 cm deep plastic film to prevent the cross penetration of water and fertilizer. The drip tapes were laid under plastic film, the dripper flow rate was 2 L/h. The rice variety was 96D10. Ternary quadratic regression model was used to fit relationship between yield and three treatments in 2012. The results showed that the model could well fit the relationship between the actual yield and irrigation, N and P fertilizer with the determination coefficient R2 of 0.981. The main factor analysis for the model revealed that the effects of three treatments on yield was ordered in irrigation quotaNP2O5 fertilizers. In addition, the model was used to obtain optimal combinations of treatments for target yield and results showed that: 1) when the target yield of rice was 5000-6500 kg/hm^2, the irrigation quota should be 2218.9-3087.3 m^3/hm^2, the N and P2O5 fertilizers was 131.7-236.9 and 66.1-109.5 kg/hm^2, respectively; 2)when the yield of rice was 6500-8000 kg/hm^2, the irrigation quota should be 4219.6-5157.6 m^3/h