Aquaponics combines aquaculture and hydroponics, offering methods to produce fish and plants. However, optimization of its nitrogen transformation processes, which would lead to higher nitrogen utilization efficiency (NUE) and lower nitrous oxide (N2O) emission, is still a daunting challenge. This study investigated these issues by using biochar and zerovalent iron (ZVI) with low (LD) and high (HD) doses. Results showed that LD improved NUE by 15%, reaching 57%, along with a significant 36% reduction in N2O emissions. Conversely, denitrifying bacteria were disturbed in HD due to incomplete denitrification, resulting in higher N2O emissions. Microbial analysis showed that the abundance of denitrifying bacteria increased from 12% to 24% in LD, compared with the control, leading to lower N2O emissions and optimized nitrogen cycling. These findings suggested that using the appropriate proportion of biochar and ZVI would be a promising approach to enhance the sustainability and productivity of aquaponics systems.

中文翻译：

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使用生物炭和零价铁在基于媒体的水生系统中增强氮转化


鱼菜共生结合了水产养殖和水培，提供了生产鱼类和植物的方法。然而，优化其氮转化过程，从而提高氮利用效率 （NUE） 和降低一氧化二氮 （N2O） 排放，仍然是一项艰巨的挑战。本研究通过使用低剂量 （LD） 和高剂量 （HD） 的生物炭和零价铁 （ZVI） 来调查这些问题。结果显示，LD 将 NUE 提高了 15%，达到 57%，同时 N2O 排放量显着减少了 36%。相反，由于反硝化不完全，反硝化细菌在 HD 中受到干扰，导致更高的 N2O 排放。微生物分析表明，与对照相比，LD 中反氮化细菌的丰度从 12% 增加到 24%，从而降低了 N2O 排放并优化了氮循环。这些发现表明，使用适当比例的生物炭和 ZVI 将是提高水生生物系统的可持续性和生产力的一种有前途的方法。