融合热成像-遥感的黑河中游绿洲耗水特征研究

Evapotranspiration is an important process and consume most of the oasis water resources, thus accurate estimates of evapotranspiration is critical for understanding hydrological processes and the establishment of water resources management strategies. Due to limitations of heterogeneity, scale, and research methods, it was also considered as one of the most difficult issues in the related research field, and faced several challenges. The quantification of water consumption is still not clear, and the precision of some conventional estimation algorithms is relatively low, it cannot tell the distribution of water consumption continuously, therefore cannot meet the need of water resources management. Based on the data accumulation and our study experience in evapotranspiration in the Heihe River Basin, by the approaches of thermal infrared remote sensing monitoring and model development, and fully integration of thermal infrared and remote sensing technology, this proposed project are going to develop a new method of water consumption estimation that can fit the arid oasis, and then to explore the continuous characteristic of water consumption under changing environment. This research will not only provide useful support for the improvement of water use efficiency, but also important for water resources allocation, and water resources sustainable development for the arid oasis.

绿洲蒸散耗水是绿洲水资源的最终消耗，是干旱区绿洲水资源配置的基础，因此干旱区绿洲耗水的准确估算变的尤为迫切和关键。然而由于地表异质性、尺度及研究方法等限制，使得干旱区绿洲蒸散耗水的准确量化变得比较困难。变化环境下的干旱区绿洲耗水量化还不够清楚，耗水量分析的时空精细度不能满足区域化管理的需求，且时空连续性不够。基于黑河流域的研究积累及蒸散发的研究基础，本项目将通过野外热红外观测、遥感模型开发等手段，充分融合热成像、遥感技术，发展适宜于干旱区绿洲耗水的新方法，旨在探索变化环境下具有一定时空连续性的黑河中游绿洲耗水特征，从而为绿洲水分利用效率提升、绿洲水资源合理配置及维系变化环境下的绿洲水资源可持续发展提供重要的科学依据。

绿洲蒸散耗水是绿洲水资源的最终消耗，是干旱区绿洲水资源配置的基础，因此干旱区绿洲耗水的准确估算尤为迫切和关键。然而由于地表异质性、尺度及研究方法等限制，使得干旱区绿洲蒸散耗水的准确量化变得比较困难。变化环境下的干旱区绿洲耗水量化还不够清楚，耗水量分析的时空精细度不满足区域化管理的需求，且时空连续性不够。本项目基于黑河流域的研究积累及蒸散发的研究基础，通过野外热红外观测、遥感模型开发等手段，充分融合热红外遥感、MODIS和Landsat8卫星遥感，发展了适宜于干旱区的耗水方法，探索了变化环境下具有一定时空连续性的黑河中游绿洲耗水特征。基于绿洲耗水特征，初步分析了空-地不同尺度下蒸散发耗水的差异，定量表征了其尺度效应，预测了变化环境下绿洲耗水特征，及在时间和空间上的分配。研究发现空地遥感地表温度和耗水相关性与下垫面性质密切相关，在异质性地表上，空-地尺度对模型估算ET的影响较小，尺度效应不明显，同时定量解析发现地表潜热通量对地表温度的敏感性较大，5%的地表温度差异，将会导致超过10%的潜热通量的变化。该项目研究为绿洲水分利用效率提升、绿洲水资源合理配置及维系变化环境下的绿洲水资源可持续发展提供重要的科学依据。