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- 2018
不同下限基点温度对积温模型模拟效果的影响
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Abstract:
为探究不同下限基点温度对作物发育阶段积温稳定性和对发育期模拟效果的影响,本研究基于一个下限温度的线性生长假设,以1990-2015年北京密云冬小麦抽穗至成熟期为例,统计设定下限温度5.0~15.0℃不同基点温度的阶段活动积温和有效积温,分析活动积温和有效积温这2种积温模型的阶段积温及其标准偏差和变异系数随下限温度的变化情况,并以模拟均方根误差和模拟准确率为指标对比分析下限温度指标对积温模型模拟效果的影响。结果表明:阶段积温随下限温度而变化,有效积温随下限温度升高而降低的趋势和程度比活动积温更快;阶段活动积温大于有效积温,且两者差值随着下限温度的升高而增大;在一定的下限温度范围内,以标准偏差为指标时有效积温绝对稳定度优于活动积温,而以变异系数为指标时则活动积温相对较有效积温相对稳定;以均方根误差检验模拟效果,则阶段活动积温模拟效果优于有效积温;以发育期模拟误差在2 d以内表征模拟准确率时,2种积温模型的模拟效果随下限温度而变化,下限温度在5.0~12.5℃时,有效积温的模拟准确率高于活动积温的,而当下限温度≥ 12.5℃时,活动积温的模拟准确率大于有效积温的。
To explore the impact of base temperatures on growing degree-day (GDD) and simulation effect of GDD model on crop development phases,Miyun winter wheat developmental phase data covering heading-maturity periods from 1990 to 2015 were analyzed.Active growing degree-day (GDDA) and effective growing degree-day (GDDE) were calculated based on linear growth assumptions using a base temperature range of 5 to 15℃.Stability variations of GDD models,and simulation effects of GDD models on crop developmental phases were analyzed with different base temperatures (Tb).The results showed that:The stability and simulation effect of GDDA model were better than those of GDDE model based on root-mean-square error (RMSE) and coefficient of variance (CV) values of modeled results;The simulation accuracy (error<2 days) of GDD varied with Tb within the range of 5.0 to 12.5℃.GDDE simulations were more accurate than GDDA when Tb was less than 12.5℃.However it was the opposite when Tb was more than 12.5℃.