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Updated: Jan 9, 2026
12:44
Watershed Planning within a Quantitative Scenario Analysis Framework
Published on: July 24, 2016
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Predicting Algae Occurrence and Identifying Influencing Factors in Two Adjacent Weirs Installed Upstream and
Seong-Jik Park1,2, Gyesik Lee3
1Department of Bioresources and Rural System Engineering, Hankyong National University, Anseong, Republic of Korea.
Summary
Algal blooms in the Yeongsan River are driven by low discharge and influenced by upstream conditions. Understanding these factors, like water temperature and organic carbon, improves prediction and management of chlorophyll-a concentrations.
Area of Science:
- Environmental Science
- Water Resource Management
- Ecology
Background:
- Chlorophyll-a (Chl-a) concentrations are key indicators of algal blooms in river systems.
- Regulated rivers with weirs present complex challenges for water quality management.
- Understanding spatial and temporal drivers of Chl-a is crucial for effective bloom mitigation.
Purpose of the Study:
- To identify primary drivers of Chl-a variations at Seungchon Weir (SC Weir) and Juksan Weir (JS Weir).
- To enhance the prediction accuracy of Chl-a concentrations in the Yeongsan River.
- To investigate conditions leading to extreme algal blooms.
Main Methods:
- Utilized over a decade of high-frequency monitoring data.
- Employed a gradient boosting (GB) regression model for analysis.
- Analyzed spatial-temporal variations and predictor importance for Chl-a.
Main Results:
- Extreme Chl-a concentrations (>100 μg/L) at JS Weir occurred under low discharge (<20 m³/s).
- Diatom blooms dominated JS Weir in colder months, contrary to typical summer bloom expectations.
- Water temperature, total organic carbon, and upstream parameters significantly influenced Chl-a; a lagged discharge effect was observed.
Conclusions:
- Upstream data integration improved downstream bloom prediction, highlighting river connectivity.
- Coordinated weir operation and upstream nutrient management are essential for mitigating algal blooms.
- Findings support improved water quality and ecosystem health in regulated river systems.
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