State Key Laboratory of Resources and Environmental Information System, Institute of Geographical Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China.
Water Sci Technol. 2012;66(5):927-33. doi: 10.2166/wst.2012.257.
Enhancing water use efficiency (WUE) is the key approach to maintain sustainable water resource supply. Due to the complexity of the water cycle, accurate estimation of WUE at the regional scale is a challenging task. Here we presented a framework of relative water use efficiency (RWUE). According to the linkage between RWUE and land use types, assessment of WUE at a regional scale could be performed operationally. This approach was evaluated in a study area, Tuhai-Majia Basin, North China. Based on remote sensing-derived evapotranspiration (ET) and land use data, regional WUE were assessed accordingly. The mean RWUE of agriculture, ecosystem and total basin in 2005 was 60.12, 30.07 and 62.5%, respectively. Spatial analysis showed that the agricultural WUE played the dominant role in water-saving of the study area; water management of unused land (RWUE of 2005 was 5.46%), especially wetland protection and other unused land development, will contribute significantly to ecological RWUE improvement. Temporal analysis indicated that there was considerable inter-annual variability in RWUE time series profiles. The agricultural interlude period might be important for enhancing WUE in the Tuhai-Majia Basin. In general, the results indicated that the RWUE-based method was an efficient and simple method to evaluate WUE at regional scale.
提高水利用效率（WUE）是维持可持续水资源供应的关键途径。由于水循环的复杂性，准确估计区域尺度的 WUE 是一项具有挑战性的任务。在这里，我们提出了相对水利用效率（RWUE）的框架。根据 RWUE 与土地利用类型的联系，可以在区域尺度上进行 WUE 的评估。该方法在华北图海河玛加流域研究区进行了评估。基于遥感衍生的蒸散量（ET）和土地利用数据，对区域 WUE 进行了评估。2005 年农业、生态系统和整个流域的平均 RWUE 分别为 60.12%、30.07%和 62.5%。空间分析表明，农业 WUE 在研究区的节水方面发挥了主导作用；未利用土地的水资源管理（2005 年的 RWUE 为 5.46%），特别是湿地保护和其他未利用土地的开发，将显著促进生态 RWUE 的提高。时间分析表明，RWUE 时间序列曲线存在相当大的年际变化。农业间歇期可能对提高图海河玛加流域的 WUE 很重要。总的来说，结果表明，基于 RWUE 的方法是评估区域尺度 WUE 的一种有效且简单的方法。
