基于DSSAT模拟的不同水分利用效率指标区域评价差异研究

The Differences of Variety Water Use Efficiency Indices in Regional Evaluation Based on DSSAT Simulation

为研究不同水分利用效率评价指标在区域评价方面的差异、相关关系和适用性,利用DSSAT-CERESWheat模型模拟得到不同定义下的农田总供水分利用效率(WUEg)、广义水分利用效率(WUEu)、作物水分生产率(WP)和灌溉水利用效率(WUEi)及真实灌溉水利用效率(WUEti)5个常用评价指标,分析得出:1 WUEu与WUEg站点间、年际间及区域水平评价结果均一致,推荐使用WUEg;2WUEi不能表征真实的灌溉水利用效率,但黄淮海区域水平WUEi表征结果实则接近总水分利用效率;3WUEti站点和区域水平均难以计算不方便使用;4站点水平各指标相关关系不同,但区域水平各指标间均呈良好的正相关性。站点和区域水平不同指标评价结果均有差异;站点水平WP评价结果最稳定,区域水平WUEg评价结果最稳定。

In order to quantify the differences, correlation and use conditions between different forms of water use efficiency evaluation indi- ces, this paper calculates water use efficiency under 5 different definitions by DSSAT-CERES-Wheat model simulation, including five com- monly used evaluation indices, namely farmland total water use efficiency （ WUEg）, generalized water resources use efficiency （ WUEu ）, crop water productivity （ WP）, irrigation water use efficiency （ WUEi ） and real irrigation water use efficiency（ WUEti ）. The research con- cludes that： ①The evaluation results of WUEu and WUEg are consistent among the interannual, site level and regional level. ② WUEi can＇t represent the real irrigation water use efficiency, but WUEi represents the total water use efficiency in Huang huaihai area. ③ WUEtl is hard to calculate and inconvenient to use on site level and regional level. ④Pearson＇s correlation coefficient （R） is different among variety water use efficiency indices on site level, but in a good positive correlation on regional level. The conclusion is that there are differences among the evaluation results of variety water use efficiency indices on site level and regional level. The evaluation results of WP are the most stable on site level and WUEg on regional level.