铁基生物炭海绵与沉水植物协同净化水体中的氮磷

为探讨铁基生物炭海绵与沉水植物协同净化系统对农田退水中氮磷的去除效果，以苦草、伊乐藻、金鱼藻3种沉水植物和铁基生物炭海绵为材料，通过动态循环水模拟渠道的方式，研究不同净化系统对农田退水中总磷、总氮、氨氮的去除效果。结果表明：3种沉水植物均能在较高氮磷浓度农田退水中生长发育，株高及生物量有明显增长。在单一沉水植物净化系统中，金鱼藻对总磷的去除效率最高，达到29.85%，苦草对总氮的去除效率最高，为35.03%，金鱼藻对氨氮的去除效率最高，为83.09%。铁基生物炭与金鱼草协同净化系统对总磷和氨氮的去除效率最高，分别达到56.00%和91.86%，铁基生物炭与苦草协同净化系统对总氮的去除效率最高，为54.05%。研究表明，铁基生物炭海绵与沉水植物协同净化系统对氮磷的去除效果全面优于单一沉水植物净化系统。

Iron-based biochar sponge and submerged plant synergistic purification on nitrogen and phosphorus in water

This study aimed to better understand the effects of an iron-based biochar sponge and submerged plant synergism purification system on nitrogen and phosphorus removal from farmland drainage. The effects of different purification systems on total phosphorus, total nitrogen, and ammonia nitrogen levels in farmland drainage were studied using three submerged plants, Vallisneria natans, Elodea spp.,Ceratophyllum demersum, and an iron-based biochar sponge. The results showed that the three submerged plants could grow and develop well in farmland drainage with high nitrogen and phosphorus concentrations, and the plant height and biomass increased significantly. In the single submerged plant purification system, Ceratophyllum demersum had the highest total phosphorus removal efficiency, reaching 29.85%; Vallisneria natans had the highest total nitrogen removal efficiency, reaching 35.03%; and Ceratophyllum demersum had the highest ammonia nitrogen removal efficiency, reaching 83.09%. The highest total phosphorus and ammonia nitrogen removal efficiencies were observed in the iron-based biochar and Ceratophyllum demersum synergistic purification system, reaching 56.00% and 91.86%, respectively. The total nitrogen removal efficiency in the iron-based biochar and Vallisneria natans synergistic purification system was the highest, reaching 54.05%. The results show that the removal of nitrogen and phosphorus in the synergistic purification system of an ironbased biochar sponge and submerged plant is better than that of a single submerged plant purification system.