This study aimed to compare the effect of different phosphate additives including superphosphate (CP) and MP [Mg(OH) + HPO] on nitrogen conversion, humus fractions formation and bacterial community in food waste compost. The results showed the ratio of humic acid nitrogen in total nitrogen (HA-N/TN) in CP increased by 49 %. Ammonium nitrogen accumulation was increased by 75 % (CP) and 44 % (MP). Spectroscopic techniques proved that phosphate addition facilitated the formation of complex structures in HA. CP enhanced the dominance of , while and were improved in MP. Structural equation modeling and network analysis demonstrated that ammonium nitrogen can be converted to HA-N and has positive effects on bacterial composition, reducing sugars and amino acids, especially in CP with more clustered network and synergic bacterial interactions. Therefore, the addition of phosphate provides a new idea to regulate the retained nitrogen toward humification in composting.

中文翻译：

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磷酸盐添加剂通过调节前体和堆肥细菌群落促进腐植酸碳和氮骨架的形成

本研究旨在比较不同磷酸盐添加剂（包括过磷酸钙 (CP) 和 MP [Mg(OH) + HPO]）对食物垃圾堆肥中氮转化、腐殖质部分形成和细菌群落的影响。结果表明，CP中腐殖酸氮占总氮的比例（HA-N/TN）增加了49%。铵态氮积累量增加了 75% (CP) 和 44% (MP)。光谱技术证明磷酸盐的添加促进了HA中复杂结构的形成。 CP 增强了 、 、 的优势，而 和 则在 MP 中得到了提高。结构方程模型和网络分析表明，铵态氮可以转化为HA-N，并对细菌组成、还原糖和氨基酸产生积极影响，特别是在具有更多簇网络和协同细菌相互作用的CP中。因此，磷酸盐的添加为调节堆肥中滞留氮的腐殖化提供了新的思路。