基于东北玉米区域动力模型的低温冷害预报应用研究

STUDY OF LOW TEMPERATURE DAMAGE PREDICTION APPLICATIONS IN EN, CHINA BASED ON A SCALING-UP MAIZE DYNAMIC MODEL

在田间试验资料基础上 ,采用改进的发育模型和分区作物参数 ,结合前人有关研究成果建立了东北玉米区域动力模型 ,并利用模型模拟了 1 2站 40年 ( 1 961～ 2 0 0 0年 )玉米生长发育过程。确定抽雄期延迟天数为低温冷害指标 ,分析了历史低温冷害年及减产情况。模拟了典型冷害年和 40年气候平均的 0 .2 5°× 0 .2 5°网格点玉米生长发育过程 ,探讨了与区域气候模式结合进行低温冷害预报的方法。主要结论有 :①玉米发育模型能够较好地模拟玉米发育期和发育期对低温冷害的响应 ,以抽雄期延迟天数为冷害指标评估的历史冷害发生状况基本符合历史实况。②模型有一定的模拟玉米生长量对低温冷害响应的能力 ,但还需要更多的试验数据校正品种参数 ,完善模型。③利用GIS技术 ,结合区域化的作物参数运行区域作物模型 ,是作物模型区域化应用的一种解决方案。④东北玉米区域动力模型解释性好 ,根据确定的冷害指标 ,以区域气候模式输出结果驱动玉米模型可以模拟和预测低温冷害 ,是农业气象灾害预测预报的一个有益的尝试。

A scaling up maize dynamic model in EN, China is established,including an improved heat unit development model and crop parameters in the certain regions based on the maize field experiments data and predecessors' studies on crop simulation models. The development and growth processes are simulated for 12 stations using daily weather data for 40 years (1961～2000). The index for low temperature damage is defined by the days of tasseling postponed. The years with low temperature damage and the related reduction of yield are analyzed using the index. The development and growth processes in the grids with 0.25°×0.25°are simulated for the year with typical low temperature damage and for mean climate condition in 40 years. The experiment on prediction method of low temperature damage using maize simulation model combined with regional climate model is carried out. The main conclusions are as follows: (1) The model of development stage well simulates maize development stages and the response of development stages to low temperature damage. Using the index for low temperature damage defined by the days of tasseling postponed, the degree of low temperature damage is estimated. The results are very well and are conformed by historical cases. (2) The model can basically simulate responses of maize biomass to low temperature damage; but the parameters of cultivar should be calibrated by more measured experiment data, and the model will be modified further. (3) It is a resolution to scaling up application of crop models to determine the crop parameters in these areas and to apply GIS. (4) The method for scaling up maize dynamic model is of more mechanism and explanatory. Running maize model, according to low temperature damage index and output of regional climate models, it is easily to simulate and predict occurrence degree of low temperature damage.