Biochar was added into constructed wetlands (CWs) as an amendment to the main substrate (i.e., coarse gravel) for improving the removal efficiency of pollutants and mitigating greenhouse gas (GHG) emissions. Four types of mesocosm-scale CWs, i.e., unamended subsurface batch constructed wetland (SSBCWs) and surface batch CWs (SBCWs), and biochar-amended SSBCWs and SBCWs, were established in this study. The SSBCWs outperformed SBCWs in both removing pollutants (particularly COD, NO₃^--N and TN) and reducing the global warming potential (GWP), irrespective of adding biochar or not. The amendment of biochar improved the efficacy of CWs for removing pollutants and mitigating GHG emissions in both configurations of CWs. The highest removal percentages of COD (89.6%), NO₃^--N (89.2%) and TN (92.5%) were obtained in biochar-amended SSBCWs, followed by unamended SSBCWs, biochar-amended SBCWs, and unamended SBCWs. The lowest GWP (5.252 mg/m²/h) was simultaneously obtained in biochar-amended SSBCWs, and the addition of biochar reduced GWP by 57.3% and 3.0% for SSBCWs and SBCWs, respectively. The abatement of GHG by biochar addition was mainly reflected in reduction of N₂O fluxes, while the CH₄ fluxes were promoted and the CO₂ fluxes were not affected. The quantitative PCR results indicate that the reduced N₂O fluxes in biochar-amended CWs were driven by the enhanced transcription of the nosZ gene and the ratio of nosZ / (nirS + nirK). This study demonstrates that biochar-amended SSBCWs can be an ideal alternative for design and application of CWs for removing pollutants and abating GHG emissions in the future.

生物炭被添加到人工湿地（CW）中，作为对主要基质（即粗砾石）的修正，以提高污染物的去除效率并减少温室气体（GHG）的排放。在这项研究中，建立了四种类型的中观规模化的连续水，即未经修改的地下分批人工湿地（SSBCW）和地面分批的湿地（SBCW），以及经生物炭改性的SSBCW和SBCW。无论是否添加生物炭，SSBCW在去除污染物（特别是COD，NO ₃ ^-- N和TN）和降低全球变暖潜能值（GWP）方面均优于SBCWs 。对生物炭的修正提高了两种废物配置中化工厂清除污染物和减少温室气体排放的功效。COD（89.6％）的最高百分比去除，NO ₃ ^-在生物炭改性的SSBCW中获得了-N（89.2％）和TN（92.5％），随后是未改性的SSBCW，生物炭改性的SBCW和未改性的SBCW。在经生物炭改性的SSBCW中，同时获得了最低的GWP（5.252 mg / m ² / h），而添加生物炭后，SSBCW和SBCW的GWP分别降低了57.3％和3.0％。通过添加生物炭减少温室气体主要体现在减少N ₂ O通量，而促进CH ₄通量而不影响CO ₂通量。定量PCR结果表明，生物炭修饰的CW中N ₂ O通量的减少是由nos Z基因转录增强和nos Z /（nir S + nir K）。这项研究表明，经过生物炭改良的SSBCW可以成为CW的设计和应用的理想替代方案，以在将来去除污染物和减少温室气体排放。