Efficient Pollutant Removal and Low-Carbon Emission Mechanisms in Constructed Wetlands Synergistically Driven by Low COD/N Ratio and Coastal Location
Abstract
:1. Introduction
2. Materials and Methods
2.1. Description of Experimental Wetlands
2.2. Sample Collection and Analysis
2.2.1. Liquid and Soil Sample Collection
2.2.2. GHG Collection
2.2.3. Gas Detection and Analysis
2.2.4. The Calculation of Greenhouse Gas Flux
2.3. Global Warming Potential (GWP) in the Wetlands
2.4. Statistical Analysis
3. Results
3.1. Pollutant Removal
3.1.1. COD Removal
3.1.2. TN Removal
3.1.3. NH4+-N Removal
3.2. CH4 Flux
3.3. N2O Flux
3.4. CO2 Flux
3.5. Global Warming Potential (GWP) from Different Wetlands
3.6. The Correlation of GHG with the Environmental Factors in Constructed Wetlands
4. Discussion
4.1. Pollutant Removal Efficiency
4.2. Effect of Influent COD/N Ratio on GHG Emissions
4.2.1. CH4 Flux
4.2.2. N2O Flux
4.2.3. CO2 Flux
4.2.4. GWP
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
Abbreviations
CWs | Constructed wetlands |
GHGs | Greenhouse gases |
COD/N | Chemical oxygen demand to nitrogen |
GWP | Global warming potential |
TC | Total carbon |
TN | Total nitrogen |
NH4+-N | Ammonia nitrogen |
CO2-eq | Carbon dioxide equivalent |
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Soil pH | Soil Moisture Content (%) | Soil Carbon Content (%) | Soil Nitrogen Content (%) | |
---|---|---|---|---|
CW-1 | 6.71 ± 0.64 | 5.14 ± 1.14 | 0.69 ± 0.38 | 0.11 ± 0.06 |
CW-2 | 7.69 ± 0.19 | 25.84 ± 9.84 | 1.43 ± 0.31 | 0.07 ± 0.03 |
CW-3 | 7.28 ± 0.11 | 20.78 ± 6.04 | 0.89 ± 0.19 | 0.12 ± 0.03 |
CW-4 | 7.80 ± 0.09 | 8.19 ± 2.38 | 0.64 ± 0.01 | 0.05 ± 0.01 |
CW-5 | 6.32 ± 0.23 | 16.23 ± 2.17 | 0.28 ± 0.02 | 0.07 ± 0.01 |
Average Temperature (°C) | COD/N | Influent COD (mg/L) | Influent NH4+-N (mg/L) | Influent TN (mg/L) | |
---|---|---|---|---|---|
CW-1 | 26.8 | 3 | 34.28 | 0.50 | 10.23 |
CW-2 | 20.3 | 3 | 26.97 | 0.16 | 8.64 |
CW-3 | 25.8 | 6 | 33.77 | 0.23 | 5.64 |
CW-4 | 28.2 | 8 | 30.62 | 0.04 | 3.74 |
CW-5 | 14.0 | >40 | 202.79 | 2.30 | 4.65 |
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Wu, W.; Mairemu, M.; Zheng, X.; Xiong, Y.; Xu, S.; Jiang, C.; Zhang, X.; Wang, J.; Liu, X.; Zhuang, X. Efficient Pollutant Removal and Low-Carbon Emission Mechanisms in Constructed Wetlands Synergistically Driven by Low COD/N Ratio and Coastal Location. Sustainability 2025, 17, 4168. https://doi.org/10.3390/su17094168
Wu W, Mairemu M, Zheng X, Xiong Y, Xu S, Jiang C, Zhang X, Wang J, Liu X, Zhuang X. Efficient Pollutant Removal and Low-Carbon Emission Mechanisms in Constructed Wetlands Synergistically Driven by Low COD/N Ratio and Coastal Location. Sustainability. 2025; 17(9):4168. https://doi.org/10.3390/su17094168
Chicago/Turabian StyleWu, Wenzheng, Maihaiti Mairemu, Xiaoxu Zheng, Yanghui Xiong, Shengjun Xu, Cancan Jiang, Xupo Zhang, Jinglin Wang, Xiaoxuan Liu, and Xuliang Zhuang. 2025. "Efficient Pollutant Removal and Low-Carbon Emission Mechanisms in Constructed Wetlands Synergistically Driven by Low COD/N Ratio and Coastal Location" Sustainability 17, no. 9: 4168. https://doi.org/10.3390/su17094168
APA StyleWu, W., Mairemu, M., Zheng, X., Xiong, Y., Xu, S., Jiang, C., Zhang, X., Wang, J., Liu, X., & Zhuang, X. (2025). Efficient Pollutant Removal and Low-Carbon Emission Mechanisms in Constructed Wetlands Synergistically Driven by Low COD/N Ratio and Coastal Location. Sustainability, 17(9), 4168. https://doi.org/10.3390/su17094168