Identification and emergy quantification methods of water shortage loss in regional water use system under extreme drought conditions

Under extreme drought conditions, water shortage loss assessment is essential for regional water use system management decisions and the development of drought mitigation measures. This study addresses current research on economic losses in water use systems, which often overlooks the social and ecological losses caused by drought mitigation measures. The impact of measures such as water use compression, industrial structure adjustment, and hierarchical, zoned and time-divided water allocation on various water use subsystems is analysed. A comprehensive framework for quantifying regional water shortage losses was established using emergy analysis, enabling unified evaluation of multidimensional impacts. The framework was applied to quantify water use system losses in Chuxiong Prefecture, Yunnan Province, during the severe drought event in 2009 ~ 2012. The results show that the overall trend of water shortage losses in the water use system initially increased before gradually declining, with subsystem losses ranked as follows: domestic water > agricultural water > industrial water > ecological water. This study offers a new perspective for evaluating water shortage losses under extreme drought conditions.