华北平原不同等级干旱对冬小麦产量的影响

华北平原是中国重要的粮食生产基地,其中冬小麦播种面积和产量均居中国首位,在国家粮食安全中具有重要作用,干旱是影响该区域冬小麦产量的最主要农业气象灾害。该研究基于华北平原44个气象站点1981—2017年的逐日气象数据以及作物、土壤和田间管理资料,以作物水分亏缺指数为农业干旱指标,基于调参验证后的农业生产系统模型(Agricultural Production Systems Simulater,APSIM),评估了冬小麦生长发育中后期各生育阶段不同等级干旱对冬小麦单产和总产的影响。结果表明,冬小麦拔节-开花和开花-成熟阶段干旱造成冬小麦减产率空间上均呈北高南低的分布特征,且开花-成熟阶段干旱引起的减产率(26.8%)高于拔节-开花阶段干旱引起的减产率(19.1%),区域间比较均表现为干旱对京津冀地区冬小麦单产影响最大,对河南省冬小麦单产影响最小;随着干旱等级的加重减产率增大,开花-成熟阶段轻旱、中旱和重旱的减产率分别为16.5%、32.8%和44.9%,拔节-开花阶段轻旱、中旱和重旱的减产率分别为10.3%、18.8%和28.6%。结合冬小麦实际播种面积得到各生育阶段干旱对总产的影响,区域间比较均表现为干旱对山东省冬小麦总产影响最大,对河南省冬小麦总产影响最小。

Impacts of different grades of drought on winter wheat yield in North China Plain

Abstract: North China Plain is one of the most important crop production bases in China, particularly on the sowing area and winter wheat yield in national food security. Meanwhile, the most serious agro-meteorological disaster, drought has posed a great threat to the yield of winter wheat in this region. Therefore, this study aims to explore the impacts of different drought grades on the yield of winter wheat using the management data of crop, soil, and field. The daily weather data was also collected from 44 meteorological stations in the North China Plain from 1981 to 2017. The crop water deficit index (CWDI) was employed for the agricultural drought. A validated agricultural production systems simulator (APSIM) was utilized to evaluate the effects of different drought grades on the yield and production of winter wheat during growing stages from jointing to flowering date and from flowering to maturity date. The results showed that there was a spatially higher yield reduction rate in the north than the south in the study area when the drought occurred during growing stages from jointing to flowering date, and from flowering to maturity date of winter wheat. Furthermore, the yield reduction rate caused by drought during the growing stage from flowering to maturity date was higher than that during the growing stage from jointing to flowering date (26.8% vs. 19.1%). In addition, the winter wheat yield suffered the most from drought in the Beijing-Tianjin-Hebei region, whereas the least in Henan Province. The yield reduction rate increased significantly, with the increase of drought grades. Specifically, the yield reduction rates under the light, moderate, and severe drought during the stage from flowering to maturity date were 16.5% (3.0%~47.8%), 32.8% (9.9%~54.2%), and 44.9% (11.9%~63.5%), respectively. The yield reduction rates under the light, moderate, and severe drought during the stage from jointing to flowering date were 10.3% (2.1%~25.3%), 18.8% (5.4%~36.0%), and 28.6% (10.6%~45.9%), respectively. Among three regions, the winter wheat yield suffered the most in the Beijing-Tianjin-Hebei region at the same drought level, while suffered the least in Henan province, except for the severe drought during the stage from jointing to flowering date, during which suffered the least in Shandong province. There was also a gradual increase in the effect of different grade droughts on winter wheat production from southwest to northeast actual planting areas. The winter wheat production in Shandong province suffered the most from the severe drought during growing stages from jointing to flowering date and from flowering to maturity date of winter wheat, but the least in Henan province in practice. The total yield suffered the least in the Beijing-Tianjin-Hebei region. In the case of light and moderate drought during the growing stage from jointing to flowering date, the most effect in the Beijing-Tianjin-Hebei region, and the least effect in Henan province. In the case of light and moderate drought during the growing stage from flowering to maturity date, the most effect was shown in Shandong province, while the least effect in Henan province.