Enhancing water use efficiency (WUE) at field and regional scales via innovative management is the key to coping with the challenges of water shortage. Comprehensive assessment of debris flow hazard risk is a challenging task due to the complexity of water cycle.

Researchers from Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences (IGSNRR-CAS) proposed a novel approach for assessing regional WUE based on remote sensing derived evapotranspiration (ET) , vegetation cover fraction and land use data.

A framework of relative water use efficiency (RWUE) was established according to the linkage between RWUE and land use types. The method has been evaluated at Tuhai Majia basin, North China. The agricultural, ecological and regional RWUE of this area were estimated and evaluated.

The results show that the mean RWUE of agriculture, ecosystem and total basin in 2005 was 60.12%, 30.07% and 62.5%, respectively. 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.

The project is supported by grants from State Key Lab of Resources and Environmental Information System of China, and China Postdoctoral Science Foundation （20100480437, 201104133）. The result of the research has been published on the Water Science & Technology (2012,66.5: 927-933).

CONTACT:
JIANG Dong
Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences. Beijing, China,
E-mail: jiangd@igsnrr.ac.cn