[Pollutant loading analyses and TP model calculation for eutrophication in Lichee Lake in Shenzhen]

Area of Science:

• Environmental Science
• Water Quality Management
• Limnology

Context:

• Lichee Lake in Shenzhen faces eutrophication challenges.
• In situ monitoring data over nine months were analyzed.
• Storm sewer overflow significantly impacts lake water quality.

Purpose:

• To investigate pollutant sources and loadings contributing to eutrophication in Lichee Lake.
• To assess the impact of external pollutant sources, particularly storm sewer overflow.
• To develop and validate a total phosphorus model for Lichee Lake's sub-basins.

Summary:

• Storm sewer overflow is identified as the main external pollutant source, leading to elevated total phosphorus levels (up to 0.347 mg/L).
• Sediment analysis revealed a nitrogen release rate of approximately 0.0368 g/(m2 x d) in the first week, with minimal phosphorus release under aerobic conditions.
• A validated total phosphorus model predicts that continuous daily operation of an integrated treatment project can achieve National Standard IV water quality in 2.18 days.

Impact:

• Provides crucial data for understanding eutrophication drivers in urban lakes.
• Offers a validated model for predicting water quality improvements.
• Demonstrates the efficacy of integrated treatment projects for rapid lake restoration.