东北地区玉米冷害预测评估模型改进研究

Improvement study on prediction and assessment model for chilling damage of maize in Northeast China

考虑到东北气候变暖和玉米种植范围扩大的事实,利用大量的长期观测资料,详细分析了东北玉米模型作物发育参数的时空变异特点,进行了玉米模型发育参数的区域划分,得到了反映发育特性的晚熟、偏晚熟、中熟、中早熟和早熟5个品种的熟性类型区。改进了模型发育参数,采用以年代平均发育期间累积CHU为指标的变化的发育参数,克服了气候变暖对发育参数的影响,取得了较好的模拟效果。根据作物生育过程的前后连续性和气象条件影响的复杂多样性,建立了考虑抽雄期延迟、抽雄以后热量条件和储存器官干重变化的动态、综合冷害指标,取得了有益的进展。改进后的模型和冷害指标对东北地区玉米延迟性冷害的历史拟合准确率达到95.6%,技巧评分89.5%,较原有单一指标对冷害的历史拟合率和预报检验效果有明显的改善,可应用于东北区域玉米冷害的预测和评估。

Considering the climate warming and expanding of maize growing areas, the spatiotemporal variance characteristics of phenological parameter of crop simulation for maize grown in Northeast China are analyzed based on long series of historical observation data. The phenological parameters are regionalized into 5 types reflecting the maturity features. The phenological parameters are corrected and improved, the decade averages of accumulated heat unit are used as phenological parameters of maize, which overcome the effects of climate warming. The simulations of development stages are improved. The dynamic and integrated indices of maize chilling damage in Northeast China is established based on the delay days of tasseling date, temperature condition after tasseling as well as anomaly of storage dry weight with consideration of the continuity and complexity of meteorological condition effects during growing period. The validity of the improved maize model and chilling damage indices reaches 95.6% and has a considerable raise in comparison with original single index.