基于遥感蒸散发模型的区域灌溉水有效利用系数测算方法框架设计

Study of Regional Irrigation Water Use Efficiency Calculation Method Based on Remote Evapotranspiration Model

在农业用水计量率较低、作物净灌溉用水量较难量测的现状下,最严格水资源管理灌溉用水效率考核指标的复核工作缺乏有力抓手。针对净灌溉用水量难以准确测算的问题,在考核指标复核技术体系不完善的条件下,提出融合"遥感反演-实地监测-计量经济学模型测算-数据综合分析"四位一体的方法,通过基于遥感蒸散发模型的ET测算、典型灌区直接量测、计量经济学模型的灌溉水有效利用系数测算、多学科方法数据对比分析,实现准确、快速测算区域灌溉水有效利用系数,研究结论为最严格水资源管理用水效率指标考核提供复核依据。

At present,the rate of agricultural irrigation water is biggest in regional water utilization amount. And crop net water demand is hard to be monitored accurately. So, it is hard to recheck the water use efficiency evaluation index in the most strict water management evaluation. The method in 'National irrigation water use efficiency calculation and analysis technical guide'( the GUIDE) is recommended to be applied in the most strict water resources management evaluation. The method in the GUIDE has been applied for nearly ten years and there are much application experiences in the industry. However, it is timing costly and hard to monitor the crop net water demand accurately in the present evaluation technical system. And the irrigation water use monitoring rate is so low that water use stochastic data which used in the evaluation is not so accurate. Therefore, a composite method is produced in this subject, which irrigation water use efficiency calculation based on remote evapotranspiration model, monitoring of typical irrigation areas, econometrics model,comparison analysis method are combined together, and the results can be used to recheck the evaluation index IE of the study area.