基于APSIM模型模拟水氮调控对旱地春小麦(Triticum aestivum)叶面积的影响

本研究针对水氮调控对旱地春小麦(‘定西42号’)叶面积的影响,采用大田试验数据与农业生产系统模型(agricultural production system simulator, APSIM)的结合,分别设定不同降水和施氮梯度对叶面积的变化趋势进行研究,试验获取2015-2017年定西田间试验不同水氮肥施入的试验数据,并对模型予以检验。APSIM模型对叶面积模拟精度较高,决定系数(R2=0.96)、归一化均方根误差(NRMSE=27.37%)、模型一致性指标(D=0.91)。结果表明:(1)随施氮量的增加,叶面积指数呈现先增后减的趋势;(2)随降水量的增加,叶面积整体呈现单一增长趋势;(3)水氮耦合作用中,降水量在自然降水基础上增加20%,施氮量为157.5 kg/hm2时,叶面积指数最高达2.766。本研究为田间试验水氮肥的施入量提供科学依据,为旱地春小麦增产提供了理论参考。

Simulating the Effects of Water and Nitrogen Regulationon Leaf Area of Triticum aestivum in Dryland Based on APSIM Model

In this study,the effects of water and nitrogen regulation on the leaf area of dryland spring wheat(‘Dingxi 42’)were studied.The field experiment data and the Agricultural Production System Simulator(APSIM)were used to set the trend of leaf area change with different precipitation and nitrogen application gradients.The test obtained the test data of different water and nitrogen fertilizer application in the Dingxi field test from 2015 to 2017,and tested the model.The APSIM model has higher simulation accuracy for leaf area,determination coefficient(R^2=0.96),normalized root mean square error(NRMSE=27.37%),and model consistency index(D=0.91).The results showed that:(1)With the increase of nitrogen application rate,the leaf area index increased first and then decreased;(2)With the increase of precipitation,the leaf area showed a single growth trend;(3)In the coupling of water and nitrogen,the precipitation increased by 20%on the basis of natural precipitation,and the leaf area index reached 2.766 when the nitrogen application rate was 157.5 kg/hm^2.This study provided a scientific basis for the application of water and nitrogen fertilizer in field experiment,and provided a theoretical reference for the yield increase of spring wheat in dryland.