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Updated: May 13, 2026
10:49
Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading
Published on: March 6, 2014
[Bivariate statistical model for calculating phosphorus input loads to the river from point and nonpoint sources]
Ding-Jiang Chen1, Si-Yang Sun, Ying-Na Jia
1College of Environmental Science and Resources, Zhejiang University, Hangzhou 310058, China. chendj@zju.edu.cn
Huan Jing Ke Xue= Huanjing Kexue
|March 16, 2013
Summary
A new bivariate statistical model quantifies river phosphorus pollution. Nonpoint sources (NPS) contribute 83% of total phosphorus (TP) load, with summer high flows increasing algal bloom risk.
Area of Science:
- Hydrology
- Environmental Chemistry
- Water Quality Management
Context:
- Riverine phosphorus pollution stems from point sources (PS) and nonpoint sources (NPS).
- In-stream retention processes significantly influence nutrient transport and transformation.
- Existing hydrological methods often overlook in-stream retention and upstream inflow dynamics.
Purpose:
- To develop a bivariate statistical model for estimating river phosphorus load based on flow rate and temperature.
- To differentiate and quantify phosphorus contributions from PS and NPS.
- To incorporate in-stream retention and upstream inflow into phosphorus load calculations.
Summary:
- A bivariate statistical model was developed using river monitoring data (phosphorus load, flow rate, temperature).
- The model accurately estimates monthly phosphorus loads from PS and NPS, accounting for in-stream retention.
- Applied to the Changle River, the model revealed NPS as the dominant TP source (83%), particularly during summer high flows.
Impact:
- The model provides a cost-effective tool for quantifying TP pollution, aiding district and watershed management.
- It enhances understanding of phosphorus dynamics, improving water quality management strategies.
- Identified high summer NPS loads highlight increased risk of algal blooms in downstream areas.
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