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为探索水肥协同作用对不同耕作措施下作物产量影响规律,运用在黄土丘陵区率订和验证后的APSIM(agricultural production system simulator)模型,模拟研究区近35年传统耕作(T)、免耕(NT)和免耕覆盖(NTS)措施下轮作小麦/豌豆产量,并采用多元回归分析施氮量(X1)、休闲期降水量(X2)和生育期降水量(X3)对小麦/豌豆模拟产量的水肥协同效应。结果表明,自然降水条件下3因素对不同耕作措施小麦和豌豆产量的贡献率均为:X3>X2>X1。生育期降水量和休闲期降水量对产量的贡献率均为:NTS>NT>T。T、NT和NTS措施下小麦和豌豆的产量与施氮量均呈开口向下二次抛物线型变化,但小麦最佳施氮量分别为65.0,65.5和44.5kg/hm2,豌豆的最佳施氮量分别为17.9,18.5和23.8kg/hm2,并且施氮量对小麦产量的贡献率为:NT>T>NTS,而施氮量对豌豆产量的贡献率为:NTS>NT>T。在甘肃省定西黄土丘陵区,决定小麦和豌豆产量的关键因素是降水,降水量对免耕覆盖的增产效应最为显著,且3种耕作措施条件下小麦和豌豆对施氮效应有不同的表现。
In order to explore the effect of synergistic effect of water and fertilizer on crop yield under different tillage measures, APSIM (agricultural production system simulator) model, which was calibrated and validated in the loess hilly region, was used to simulate the effects of conventional tillage (T) NT) and no-tillage cover (NTS). The multivariate regression analysis was conducted on the simulated yield of wheat / pea (X1), the precipitation during the leisure time (X2) and the precipitation during the growth period Synergistic effect of water and fertilizer. The results showed that the contribution rate of three factors under natural rainfall to wheat and pea yield under different tillage measures was: X3> X2> X1. The contribution rate of precipitation during the growing season and precipitation during the leisure period to yield was: NTS> NT> T. Under the T, NT and NTS measures, the yield and nitrogen application rate of wheat and pea showed quadratic parabola changes, but the optimal nitrogen application rates for wheat were 65.0, 65.5 and 44.5 kg / hm2, respectively Nitrogen content was 17.9, 18.5 and 23.8 kg / hm2, respectively, and the contribution rate of nitrogen application rate to wheat yield was NT> T> NTS, while the contribution rate of nitrogen application rate to pea yield was NTS> NT> T. In Dingxi loess hilly region of Gansu, the key factor to determine the yield of wheat and pea is precipitation. Precipitation is the most obvious effect of increasing yield on no-tillage, and wheat and pea have different effects on nitrogen application under the three tillage measures.