辽西北灌区玉米干旱灾害动态风险预警与玉米灌溉调控模拟研究

This project takes the irrigation area in the northwest of Liaoning province as the case study, where was severely affected by the drought disaster. And it is focused on the traditional agricultural problems about drought disaster risk assessment, the early warning and the irrigation water allocation in farmland. By studying on the basic theory of the formation mechanism of drought disaster risk and the maize irrigation control ways, this project build the early warning system and the mitigation curve of the dynamic risk of maize drought disaster, and simulate the effective irrigation of maize under different risk scenarios. They play a significant role in achieving their function in making the mitigation measures of irrigation. Based on the different growth stages of the maize, fusing the multi-source, and the integrated use of indoor and outdoor experiments, mathematical methods, dynamic simulation models of crop growth and 3S technology, the model building of the dynamic risk assessment of maize drought, the integrated and real-time of the early warning results and the effective irrigation will be achieved. The research achievements can be extended to other farmland irrigation area in China, promote the process of agricultural drought disaster risk management research, and provide the theoretical basis and technical support for relevant government departments and farmland manager to make countermeasures and mitigation plans of drought disaster. And it is also very significant to food security, reduce drought losses and efficient use of agricultural water resources.

针对传统农业干旱灾害风险评价、预警和农田灌溉水分配中存在的问题，本研究以受旱灾影响严重的辽西北地区的灌区为研究区，以玉米不同生育阶段为切入点，综合运用室内外实验、数理方法、作物生长动力模拟模型和3S 技术，通过对玉米干旱灾害风险的形成机理和玉米灌溉调控方法等基础问题的研究，融合遥感、地面观测、气象等多源数据，构建“干旱早期识别—干旱灾害动态风险评价”的玉米干旱灾害动态风险预警体系和干旱灾害动态风险缓解曲线，模拟不同风险情景下的玉米有效灌溉量，实现预警结果与有效灌溉的一体化、实时化。其研究成果可推广到我国其它农田灌区，推动农业干旱灾害风险管理研究的进程，为政府相关部门和农田管理者制定农业干旱灾害管理对策和灌溉减灾规划提供理论依据和技术支撑，对保障粮食安全、降低旱灾损失、实现农业水资源的有效利用具有重要意义。

干旱已经对我国农业生产和粮食安全带来了巨大的威胁。辽西北地区是辽宁省玉米主产地，且是辽宁省干旱发生最频繁、最严重的地区。在水资源严重紧缺、干旱灾害频发的形势下，开展辽西北灌区玉米干旱灾害动态风险预警与玉米灌溉调控模拟研究，能够避免盲目灌溉，实现农业水资源的有效利用，保障粮食安全，为农业干旱灾害管理和应急抗旱减灾研究提供理论依据和技术支撑。项目以研究区玉米不同生育阶段为切入点，结合降雨、土壤、地形及农业生产类型等资料，评价了研究区农业干旱的危险性程度；利用遥感、土壤等数据，构建了研究区玉米各生育阶段干旱早期识别模型，识别玉米的干旱程度；利用遥感数据，探讨了玉米干旱灾害脆弱性的时空变化；研究玉米各生育阶段危险性与脆弱性之间的耦合关系，构建辽西北灌区玉米不同生育阶段的干旱灾害风险评价模型，动态地监测区域玉米各生育阶段干旱灾害发生的可能性、造成损失的程度及其时空分布格局和变化特征；在此基础上构建了玉米干旱灾害风险预警体系；通过模拟玉米的生长过程，结合遥感数据，估算了干旱胁迫下的玉米潜在产量损失率；基于水分平衡原理，结合玉米各生育阶段干旱早期识别模型，估算玉米不同干旱情况下的灌溉需水量，研究缓解玉米各生育阶段干旱灾害风险的有效灌溉量时空分布特征。本项目可改变区域农业干旱灾害应急减灾模式，为区域快速制定作物防旱抗旱决策提供技术支撑，为国家粮食安全提供保障。