Identification of the critical transmission sectors and typology of industrial water use for supply-chain water pressure mitigation

The industrial system produces pressure on water resources by directly consuming the water needed for industrial production and by indirectly consuming water through intermediate inputs. To date, identifying the critical transmission sectors for supply-chain water resources pressure mitigation has been under-examined. To fill this gap in knowledge, we use a betweenness-based method in combination with the standard input-output table extended with water-resource sector accounts to identify the key transmission sectors using Zhangye City in the Heihe River Basin, China as an example. The results show that the sectors with low rankings of the production-based indicator do not consume large amounts of water resources to directly generate products, which demonstrates that these sectors have limited scope for reducing water-resource consumption. The results also indicate that those sectors having higher betweenness-based water use but lower consumption-based and production-based water use merit close attention because these sectors transmit relatively large amounts of water resources embodied in their intermediate inputs from water-intensive upstream industrial sectors. Consequently, improving production efficiency in these sectors has an indirect effect by lowering the consumption of upstream water resources. This study also shows that the betweenness-based indicator is able to provide additional information beyond that given by the usual metrics derived from the production and demand sides. Moreover, the typology of water use that we innovatively generate is able to inform corresponding and targeted sector-specific policies and strategies for mitigating water resources pressure.