基于非平稳和作物系数的黄淮海平原冬小麦干旱精细化风险预估

RISK ASSESSMENT OF WINTER WHEAT DROUGHT IN THE HUANG-HUAI-HAI PLAIN BASED ON NONSTATIONARY AND CROP COEFFICIENTS

关键词:  NSPEI-kc  时空特征  干旱脆弱性  干旱风险  黄淮海平原

Key words:  NSPEI-kc  spatio-temporal characteristics  drought vulnerability  drought risk  Huang-Huai-Hai Plain

摘要:

目的 黄淮海平原是我国冬小麦主产区和干旱易发区，水分是影响冬小麦生长发育的重要因子，水分亏缺会严重制约冬小麦生产，预估黄淮海平原冬小麦未来不同生育期的干旱风险，是实现冬小麦生产合理布局和防旱减灾的关键科学问题。方法 文章基于逐日冬小麦作物系数的NSPEI-kc干旱指数分析不同生育期的干旱脆弱性权重，利用冬小麦危险性、易灾性、防灾减灾能力以及不同生育期干旱对产量的影响权重，构建冬小麦不同生育期的干旱风险模型，分析过去和未来黄淮海平原冬小麦不同生育期干旱风险时空演变特征。结果 （1）冬小麦分蘖期对干旱响应最敏感，干旱危险性整体表现为由西向东递减，播种期与分蘖期干旱危险性指数相对较大；而易灾性和防灾减灾能力空间分布基本一致，主要表现为由西南向东北递减的规律，黄淮海平原的西南部是易灾性和防灾减灾能力高值区。（2）在SSP1-2.6情景下未来河南省西部以及河北省中北部干旱风险整体处于高风险范围内，SSP2-4.5情景末期整体干旱风险大于SSP1-2.6情景。SSP5-8.5情景下冬小麦分蘖期阶段的干旱风险明显强于其他生育期。结论 因此，建立未来不同情景下黄淮海平原冬小麦不同生育期的干旱风险预估模型，实现对冬小麦各生育期的干旱风险空间分布格局的精细化评估，为未来黄淮海平原冬小麦干旱精准监测与风险防范提供理论依据与技术支撑。

Abstract:

Water is an important factor affecting the growth and development of winter wheat in Huang-Huai-Hai (HHH) Plain, which is the main producing area and drought-prone area in China. Water deficit will seriously restrict the production of winter wheat. Estimating the drought risk of winter wheat in different growth stages in the future is the key to realize the rational distribution of winter wheat production and to prevent drought and disaster. Based on the NSPEI of daily winter wheat crop coefficient, this research analyzed the proportion of drought vulnerability in different growth periods, and used the weight of winter wheat risk, disaster susceptibility, disaster prevention and reduction ability, as well as the influence weights of drought in different growth periods on yield to build drought risk models of winter wheat in different growth periods. Temporal and spatial evolution characteristics of drought risk at different growth stages of winter wheat in HHH Plain in the past and future were analyzed. The results showed that drought of winter wheat at tillering stage had great effect on the final yield. The disaster vulnerability was mainly manifested as the law of decreasing from southwest to northeast, and the southeast of Henan, the northwest of Anhui and the central and northern of Hebei were more prone to disaster. The overall risk decreased from west to east, and the drought risk index was relatively large at sowing stage and tillering stage. The ability of disaster prevention and mitigation decreased gradually from southwest to northeast, and the high value center was in the southwest of the HHH Plain. Under the SSP1-2.6 scenario, the overall drought risk of western Henan province and central and northern Hebei province in the future was in the high risk range, and the overall drought risk at the end of the SSP2-4.5 scenario was greater than that under the SSP1-2.6 scenario. The drought risk of winter wheat at tillering stage under SSP5-8.5 was obviously stronger than that at other growth stages. Therefore, it is essential to establish a drought risk prediction model for different growth stages of winter wheat in the HHH Plain under different scenarios, achieve a refined evaluation of the spatial distribution pattern of drought risk in each growth stage of winter wheat, so as to provide a theoretical basis and technical support for accurate monitoring and risk prevention of winter wheat drought in the HHH Plain in the future.