An integrated migration and transformation model to evaluate the occurrence characteristics and environmental risks of Nitrogen and phosphorus in constructed wetland | JoVE Visualize

An integrated migration and transformation model to evaluate the occurrence characteristics and environmental risks of Nitrogen and phosphorus in constructed wetland

Hongrui Li¹, Xiaodong Ma¹, Bin Zhou²

¹School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin, 300401, China.

Chemosphere|March 28, 2021

View abstract on PubMed

Summary

A new integrated model accurately predicts nitrogen (N) and phosphorus (P) in constructed wetlands. This model, considering microbial action and plant uptake, improves understanding of pollutant dynamics and wetland function.

Area of Science:

Environmental Science
Ecology
Water Quality Management

Background:

Constructed wetlands (CWs) are crucial for water purification.
Accurate modeling of nutrient (N and P) dynamics in CWs is essential for effective management.
Conventional models often lack comprehensive factors influencing nutrient behavior.

Purpose of the Study:

To establish an integrated migration and transformation (IMT) model for evaluating nitrogen (N) and phosphorus (P) distribution in a hybrid constructed wetland.
To compare the predictive accuracy of the IMT model against conventional transformation models.
To identify key factors influencing N and P concentrations and distribution within the CW.

Main Methods:

Development of an integrated migration and transformation (IMT) model incorporating microbial action, plant absorption, sediment release, and substrate adsorption.
Application of the IMT model to assess temporal-spatial distribution of N and P in Lingang CW, Tianjin.
Utilized Principal Component Analysis (PCA) and Nemerow pollution index for water quality assessment.

Main Results:

The IMT model demonstrated superior accuracy in predicting N and P occurrence compared to conventional models.
Nitrate-N (NO3--N) was the dominant N form, and total phosphorus (TP) was at low levels (0.04-0.07 mg/L).
Dissolved oxygen (DO) significantly impacted N and P concentrations temporally; PCA identified TN, NO3--N, and DO as key water quality factors.
The Nemerow index indicated moderate overall pollution, with subsurface areas being primary pollutant removal units.

Conclusions:

The developed IMT model provides a more accurate prediction of N and P characteristics in constructed wetlands.
Temporal variations, influenced by DO, play a more significant role in N and P distribution than spatial variations.
This study offers valuable insights for environmental risk assessment and optimizing constructed wetland design and management.