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Ecological Flow Response Analysis to a Typical Strong Hydrological Alteration River in China
Rui Xia1,2,3, Hao Sun1,4, Yan Chen5,6
1State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
International Journal of Environmental Research and Public Health
|February 11, 2023
Summary
This study introduces a new method to calculate ecological flow, accounting for hydrological changes. The approach provides a more scientific basis for water resource management in rivers experiencing alterations.
Area of Science:
- Environmental Science
- Hydrology
- Ecosystem Stability
Background:
- Ecological flow is crucial for watershed ecosystem stability.
- Calculating ecological discharge under hydrological variation is a key research area.
- The Ganjiang River basin in China serves as the study area.
Purpose of the Study:
- To develop and apply a method for calculating ecological flow considering hydrological variations.
- To assess the impact of hydrological alterations on ecological flow.
- To provide a scientific basis for water resource planning and allocation.
Main Methods:
- Hydrological Alteration Diagnosis System (HADS) to identify change-points.
- Distributed Time Variation Gain Model (DTVGM) for runoff restoration.
- Probability-weighted Flow Duration Curve (PWFDC) for ecological flow calculation.
Main Results:
- Hydrological alteration detected at Waizhou Station in 1991, with increased runoff and Gini coefficient, driven by precipitation changes.
- DTVGM demonstrated high accuracy (R and NSE > 0.84) for runoff restoration.
- The proposed method accurately reflects inter-annual ecological flow variations, outperforming traditional methods.
Conclusions:
- The developed method offers a more scientific approach to calculating ecological flow under hydrological variation.
- It enables the calculation of ecological flow under various human activities like dam operations and water transfers.
- The study provides a foundation for effective water resource management in dynamic environments.
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