WOFOST模型在内蒙古河套灌区模拟玉米生长全程的适应性

Adaptability of WOFOST model to simulate the whole growth period of maize in Hetao irrigation region of Inner Mongolia

在河套灌区引入成熟的作物模型并进行适应性验证,可为进一步开展玉米生长监测及估产提供依据和基础。本文利用河套灌区巴彦淖尔农业气象试验站2012年玉米观测数据,结合当地气象、土壤资料对荷兰瓦赫宁根大学开发的WOFOST模型进行参数校准,并利用2013年玉米观测数据和2001—2011年农业气象观测资料对模型的区域适用性进行验证,获得了玉米的基本作物参数,包括各发育阶段比叶面积、最大CO2同化率、单叶光能利用率等。结果表明:通过校准作物参数,WOFOST模型可以较好地模拟LAI扩展、生物量的动态积累过程,LAI、各器官生物量及最终产量的模拟值与实测值吻合较好;独立样本检验中,模型模拟LAI的绝对偏差平均值为0.75,叶生物量、茎生物量、贮存器官生物量、地上部总生物量、产量的归一化均方根误差分别为33%、26%、17%、18%和13%;模拟2001—2011年玉米产量的归一化均方根误差为7.5%。参数校准后的模型对LAI、各器官生物量、产量的模拟结果较为符合实际,WOFOST模型能够适用于河套地区玉米生产过程生理、生态因子诊断、评估等。

Introducing a mature crop model and validating its adaptability can provide a basis for further study of maize growth monitoring and yield estimation in Hetao irrigation region. Based on the observed maize data in 2012,as well as the local weather and soil data,the WOFOST crop model developed by Wageningen University was calibrated and verified by the crop data of 2013 and agrometeorological observation data from 2001 to 2011 at Bayannur agrometeorological experiment station. The basic crop parameters were obtained,which included specific leaf area,maximum rate of CO2 assimilation,light-use efficiency of single leaf,etc. The result showed that after parameters were calibrated,WOFOST model could simulate LAI expansion and biomass accumulation well,and the simulated values on LAI,biomass of organs and yield fitted well with the observed ones. The average absolute deviation of LAI was 0. 75,and the normalized root mean square errors（ NRMSE） for dry weight of leaves,stems,storage organs,total aboveground biomass and yield were 33%,26%,17%,18%,and 13%,respectively. The NRMSE for the simulated yield from 2001 to 2011 was 7.5%. Therefore,it was reasonable and practical to simulate LAI,biomass of organs and yield by the calibrated model. WOFOST model was suitable for the diagnosis and assessment of physiological and ecological factors during maize production in the Hetao irrigation region.