Geosciences and Geophysics

To address the issue of water supplement of water-deficient rivers is important for rivers’ ecological protection and basin water resource management.Relevant researches delved into the water compensation of rivers focusing on a single river system with desired sustainable objectives.Too little research resolve this issue from a whole sustainable perspective of the entire water use system. Ecological network analysis(ENA) is a system-oriented method to reveal integrity attributes of a system and identify the complicated system interactions.In this paper, this approach is introduced to develop insights into the water supplement of water-lacking rivers from a globe angle of sustainability of water use system.We investigate the meaning and quantitative index of network efficiency and resilience,which are two essential but complementary attributes for an ecosystem’s long-term sustainability.According to optimize the water quantity and water quality in water use processes,we propose an optimal network model for analyzing the balance state of water use system.A regulative model of water use system is built as the basis for water supplement scenario analysis.A index (D),which incorporates the values of ascendency(A) and overhead(∅) of the optimal model and regulative model,is adopted to assess the sustainability of water use network under each water supplement scenario.We apply this methodology to Baiyangdian basin to illustrate the balanced network structure of water use system and achieve the best water supplement scheme.The results obtained indicate that the optimal balanced network structure for water use system of Baiyangdian basin has ascendency values ranging from 0.5419 to 0.5782.Turning out 20% of water storage capacity of Baiyangdian to water-deficient rivers can not only guarantee the ecological health of rivers,but also improve the sustainability of water use system.This research serves as a meaningful start to explore ecological network analysis as a way to guide water supplement of rivers from the perspective of sustainability of water use system.It is useful for water resource regulation and management.

Keywords:Ecological network analysis; sustainability; water use system;water supplement; rivers;Baiyangdian Basin.