Establishment of the ecological relationships and properties of the Lhasa River Basin water resources system, China

Rapid socioeconomic development poses a critical challenge to sustainable management of water resources. Further development of systems-oriented approaches and objective tools is required to allow the improved evaluation of system-level properties within water resources systems. Using the Lhasa River Basin as a case study, we categorized the water resources system into nine compartments with 22 flows, following which ecological network analysis was used to calculate a comprehensive utility matrix for the flow between compartments from 2000 to 2016 and the corresponding ecological relationships among compartments were identified. More specifically, we examined changes to the evolution of the network structure through calculating system-level indices involving total system throughput, average mutual information, development capacity, ascendency, overhead, redundancy and Finn cycling index. The results indicated that the system is dominated by exploitation relationships whereas the degree of synergism degenerated. Resilience was shown to be stronger than efficiency since 2004; therefore, the efficiency of internal flow transfer requires improvement. External pressure on the system decreased, but increasing water consumption resulted in decreasing system maturity. Such analysis provides scientific support for water resources management to improve the sustainability of water resources systems.