Influence of Meteorological Factors and Nitrogen Fertilization on Spring Wheat Yield in the Longzhong Dryland Region

Abstract

【Objective】 Longzhong is a region located over the transitional zone between the Sichuan Basin and the Loess Plateau; it has a unique climate and agriculture. This paper investigates the interactive impact of meteorological factors and nitrogen fertilization on yield of spring wheat in dryland in the region. 【Method】 The study was based on the APSIM model, using meteorological data measured from 1970 to 2017, crop growth data measured from 2016 to 2017 in zero-till mulched fields, and grain yield data measured between 2005—2009 and 2013—2015. We simulated the response of grain yield of the spring wheat to changes in next-day average temperature, average daily radiation, CO2 mass fraction, nitrogen fertilization, both individually or in combination. 【Result】 ① The simulated growing duration and grain yield agreed well with the ground-true data with R2=0.98 and NRMSE=5% for the former; and R2=0.91, NRMSE=12% and D=0.95 for the latter. ② For the three precipitation scenarios we simulated, changing meteorological factors and nitrogen fertilization individually or in combination both had a significant impact on grain yield, especially in dry years. ③ When other conditions were the same, grain yield reached its peak and showed greater stability during wet years. 【Conclusion】 Elevated precipitation not only boosted grain yield but also played a pivotal role in influencing the effects of other meteorological factors on crop growth and enhancing the efficiency of nitrogen fertilizer.

Keywords

• dryland spring wheat
• climate change
• apsim