旱地小麦在不同氮肥处理下叶面积指数变化的模拟模型研究

Model of LAI changes of dryland wheat under different nitrogen treatments

【目的】为了解旱地小麦叶片生长规律、研究旱地小麦地上部主要器官的生长规律提供科学依据.【方法】采用单株叶面积最大值作为品种遗传参数,用两段非线性方程构建了不同氮肥处理条件下旱地小麦叶面积指数变化的模型.试验采用裂区设计,获取2013-2015年兰州和定西两地试验田间不同氮肥施入和不同品种的试验数据,并对模型予以检验.【结果】在适中量氮肥施入方案下,模型对两个品种的模拟值与实测值都表现出更好的一致性和相关性;在低氮和高氮施入方案下,模型指标处在可接受范畴,其中,RMSE为0.107~0.596;R2为0.761~0.983;Me值均大于0.5.【结论】在旱地小麦全生育期的8个阶段,通过模型计算的模拟值与实测值呈显著正相关,模拟效果较好;就施肥方案而言,在适中量氮肥施入方案下,模型更加贴近实际数据,更具普适性;就品种而言,模型计算数据对‘西旱2号’的实际数据解释程度更高、有效性更强.

【Objective】In order to understand the law of leaf growth of dryland wheat,and to provide theoretical basis for the study of the main organs for dryland wheat.【Method】The maximum value of leaf area per plant was used as genetic parameter,and the simulation model of leaf area index of dryland wheat under different N treatments was constructed with two sections of nonlinear equation.Split plot design was used in the experiment,obtain the experimental data of different nitrogen fertilization and different varieties in the field of Lanzhou and Dingxi during 2013-2015,and the model was tested.【Result】Under moderate amount of nitrogen fertilizer application program,the model of the two varieties of simulated and measured values showed a better consistency and correlation;under the low nitrogen and high nitrogen fertilizer application,the model index was in an acceptable range,in which,RMSE was between 0.107 to 0.596;R2 was between 0.761 to 0.983;Me was greater than 0.5.【Conclusion】During the eight phases of the total growth period of dryland wheat,the simulated value of the model is positively correlated with the measured value,and the simulation results are better.In terms of fertilization schemes,the model is more realistic andmore general under moderate amount of nitrogen fertilization.In terms of variety,the actual data interpretation of the west drought 2 is higher and more effective.