复杂下垫面条件下冬小麦干旱机制辨析研究进展

对冬小麦干旱机制辨析研究目前主要有:冬小麦干旱灾害时空特征研究、冬小麦生长需水量研究、冬小麦生长有效降水量研究、冬小麦干旱过程的缺水环节和干旱形成机制研究、冬小麦干旱灾害风险研究。为了进一步开展冬小麦干旱研究,特别是冬小麦干旱形成机制,亟需加强的方面:一是细化需水量和有效降水量的空间格局研究,可尝试以田间试验数据为基础,综合考虑气候、地形地貌、土壤特性、植被等格网化的下垫面因素,研发中观尺度冬小麦需水量、有效降水量的新模式,同时借助格网概念,尝试将冬小麦干旱精准定位于空间格网上,为冬小麦干旱防灾减灾等提供技术支撑;二是确定冬小麦干旱的缺水环节,研究掌握冬小麦的干旱机制,可从“气候—土壤—冬小麦”系统角度出发构建缺水量空间分布模型。结合气候模式数据,对冬小麦缺水量进行深入的研究并探讨冬小麦干旱形成机制,开展不同气候变化情景下冬小麦需水量和缺水量的时空变异及模拟预测研究,识别冬小麦干旱时空演变特征,研判冬小麦干旱风险,为保障冬小麦生产提供理论依据。

Advances in the Identification of Drought Mechanism of Winter Wheat under the Influence of Complex Underlying Surface

The study on drought mechanism identification of winter wheat included studying on the spatial-temporal of winter wheat drought disasters,studying on the optimum soil moisture for growth of winter wheat,studying on the effective precipitation at growth stages for winter wheat,studying on the water shortage and the drought formation mechanism in the winter wheat drought process,studying on the drought disaster risk of winter wheat.Further research on winter wheat drought,especially the formation mechanism of winter wheat drought,the urgent scientific problems needed to be strengthened were:Based on field trial data,considering the complex underlying surface of climate,landform area,soil,vegetation by the gridding,studied on the spatial patterns of how to refine the optimum soil moisture and effective precipitation,a new model for the development of mesoscale winter wheat was to study the optimum soil moisture and effective precipitation,provided technical support for winter wheat drought disaster prevention and mitigation,and tried to locate the drought of winter wheat on the space grid accurately by the concept of grid.How to determine the water shortage link of winter wheat drought,studied and mastered the drought mechanism of winter wheat could be used to construct the spatial distribution model of water shortage from the perspective of“climate-soil-winter wheat”system.Combined with the climate model data,a thorough research on winter wheat water deficit and winter wheat drought formation mechanism was discussed in this paper,and developed the water requirement of winter wheat under the different climate change scenarios and the variation of time and space of water deficit simulation prediction research,identified the spatial and temporal evolution characteristics of winter wheat drought,hinted on winter wheat drought risk,and provided theoretical basis for winter wheat production.