SUJun-tao,XUYi-ming,SUNAi-li,et al.Influencing Factors of Nitrogen Release from Sediments of Polluted Lake in the North[J].China Water & Wastewater,2023,39(11):62-68.
Influencing Factors of Nitrogen Release from Sediments of Polluted Lake in the North
China Water & Wastewater[ISSN:1000-4062/CN:12-1073/TU]
volume:
第39卷
Number:
第11期
Page:
62-68
Column:
Date of publication:
2023-06-01
- Keywords:
- nitrogen release from sediment; nitrogen migration and transformation; response surface method; environmental factor
- Abstract:
- To explore the rule of nitrogen release from sediments in lakes in northern China and predict the risk of endogenous nitrogen release, the correlation between three factors (temperature, pH and dissolved oxygen) and nitrogen in overlying water was explored based on actual water indicators of the lake. The response surface method was used to investigate the effects of interaction between different environmental factors on the total nitrogen release rate. Multiple regressions were constructed to estimate the total annual nitrogen release from sediments and predict the most unfavorable nitrogen release factor levels. Temperature, pH and dissolved oxygen were significantly correlated with the nitrogen concentration in water, among which the pH and dissolved oxygen had more significant effects on nitrogen release rate. The interaction between dissolved oxygen and pH as well as the interaction between dissolved oxygen and temperature had a significant effect on the total nitrogen release rate. The average total annual nitrogen release from sediments in the polluted lake was 0.35 t calculated by the response surface fitting model. The most unfavorable environmental conditions for nitrogen release from the sediments were temperature of 4 ℃, dissolved oxygen of 5 mg/L and pH of 9. In this case, the predicted average nitrogen release rate was 33.565 mg/(m2·d), and the error of the measured value was less than 5%, indicating that the model had a high reliability. Controlling water pH and dissolved oxygen was a powerful means to limit nitrogen release from sediments.
Last Update:
2023-06-01