基于WOFOST模型的辽西地区典型旱年不同播期玉米干旱损失评估

针对干旱灾害频发的辽西地区, 以春玉米为研究对象, 选取WOFOST作物模型, 利用干旱胁迫控制试验数据、田间试验数据和气象数据驱动模型, 进行典型旱年的模型适用性及不同播期的干旱损失评估研究。结果表明: 经过参数校准后的WOFOST模型能够较好的模拟辽西地区典型旱年春玉米产量及损失。辽西地区不同播期受干旱的影响程度不同, 因旱减产风险随播期推迟而减小, 2015年(中旱)干旱导致的平均减产率可达59%—61%, 2018年(轻旱)可达20%—39%, 2020年(中旱)可达36%—62%。不同生育期内干旱对产量的影响程度不同, 总体上拔节期—抽雄期和抽雄期—乳熟期持续重旱对产量的影响最大, 其次是抽雄期—乳熟期、拔节期—抽雄期。玉米各生育期受干旱影响程度, 朝阳站最大, 其次是黑山站和阜新站。辽西地区在旱年, 拔节期—抽雄期发生中旱和重旱风险随播期推迟而增加, 抽雄期—乳熟期发生中旱和重旱风险随播期推迟而减少, 当拔节期—抽雄期和抽雄期—乳熟期连续发生重旱, 干旱灾损程度随播期推迟而加重, 减产率可高达46%—84%。

Evaluation of maize drought loss at different sowing dates of typical drought years in western Liaoning province based on WOFOST model

Aiming at the western Liaoning area where drought disasters occur frequently, taking spring maize as the research object, the WOFOST crop model was selected to study the model applicability in typical dry years and the evaluation of drought losses at different sowing dates.The model was driven by drought stress control test data, field test data and meteorological data.The results show that the WOFOST model after parameter calibration can better simulate the yield and loss of spring maize in typical dry years in western Liaoning province.Different sowing dates in western Liaoning province are affected by drought to different degrees, and the risk of drought reduction decreases with the delay of the sowing date.The average yield reduction rate caused by drought is about 59%-61% in 2015 (medium drought), 20%-39% in 2018 (light drought), and 36%-62% in 2020 (medium drought), respectively.The effect of drought on yield is different in different growth stages.In general, the continuous severe drought has the greatest effect on yield in joint-tasseling and tassel-milking stages, followed by tassel-milking and joint-tasseling stages.Drought in each growth period has the greatest impact on Chaoyang station, followed by Heishan station and Fuxin station.In western Liaoning province, the risk of moderate drought and severe drought in the jointing and tasseling stage increases with the sowing date, while the risk of moderate drought and severe drought in tasseling and milk-ripe stage decreases with the sowing date.When severe drought occurs continuously in the jointing and tasseling and milk-ripe stage, the degree of dry drought damage increases with the sowing date, and the yield reduction rate can be as high as 46%-84%.