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Beyond the Cascade Dams: Scale-Dependent Effects on Zooplankton Stability in River Ecosystems
Xufei Jiang1,2,3, Rixiu Zhou2, Wenzhang Dai2
1Institute of Water Sciences Zhejiang University of Water Resources and Electric Power Hangzhou China.
Ecology and Evolution
|August 14, 2026
Summary
Cascade dams alter river ecosystems, impacting zooplankton community stability differently across local and regional scales. Improved water quality enhances stability, while heavy metals reduce it, highlighting the importance of scale in dam impact assessments.
Area of Science:
- Ecology
- Environmental Science
- Freshwater Biology
Background:
- Cascade dams significantly alter river ecosystems, affecting biodiversity and community stability.
- Understanding factors influencing community stability across spatial scales is crucial for effective river management.
Purpose of the Study:
- To compare zooplankton community synchrony and stability at local and regional scales.
- To investigate the relationship between environmental variables (water quality, heavy metals) and zooplankton community stability.
Main Methods:
- Field sampling and community analysis were employed.
- Structural equation modeling was used to analyze relationships between variables.
- Zooplankton diversity, synchrony, stability, water quality, and heavy metal concentrations were assessed.
Main Results:
- Cascade dams induced complex shifts in community stability and synchrony, varying by spatial scale.
- Locally, stability correlated positively with diversity but not directly with environmental variables.
- Regionally, stability increased downstream, influenced positively by water quality and negatively by heavy metals.
Conclusions:
- Spatial scale is critical for assessing river ecosystem stability.
- Cascade dams can reduce regional stability through altered water quality.
- Management strategies should consider scale-dependent impacts of dams on aquatic communities.
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