Phosphine (PH) is an important contributor to the phosphorus cycle and is widespread in various environments. However, there are few studies on PH in constructed wetlands (CWs). In this study, lab-scale CWs and batch experiments were conducted to explore the characteristics and mechanisms of PH production in sulfur-based CWs. The results showed that the PH release flux of sulfur-based CWs varied from 0.86±0.04 ng·m·h to 1.88±0.09 ng·m·h. The dissolved PH was the main PH form in CWs and varied from 2.73 μg·L to 4.08 μg·L. The matrix-bound PH was a staging reservoir for PH and increased with substrate depth. In addition, the sulfur-based substrates had a significant improvement on PH production. Elemental sulfur is more conducive to PH production than pyrite. Moreover, there was a significant positive correlation between PH production, the gene, and nicotinamide adenine dinucleotide (NADH) NADH might catalyze the phosphate reduction process. And the final stage of the dissimilatory sulfate reduction pathway driven by the gene might also provide energy for phosphate reduction. The migration and transformation of PH increased the available P (Resin-P and NaHCO-P) from 35 % to 56 % in sulfur-based CW, and the P adsorption capacity was improved by 12 %. The higher proportion of available P increased the plant uptake rate of P by 17 %. This study improves the understanding of the phosphorus cycle in sulfur-based CW and provides new insight into the long-term stable operation of CWs.

中文翻译：

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硫基人工湿地磷化氢产生特征及机制

磷化氢（PH）是磷循环的重要贡献者，广泛存在于各种环境中。然而，关于人工湿地（CWs）PH的研究很少。本研究通过实验室规模的化武和批量实验来探索硫基化武中PH产生的特征和机制。结果表明，硫基水的PH释放通量范围为0.86±0.04 ng·m·h~1.88±0.09 ng·m·h。溶解PH是CW中的主要PH形式，变化范围为2.73 μg·L至4.08 μg·L。基质结合的 PH 是 PH 的分级储存库，并随着基质深度的增加而增加。此外，硫基基质对PH产生有显着的改善。单质硫比黄铁矿更有利于PH的产生。此外，PH的产生、基因和烟酰胺腺嘌呤二核苷酸(NADH)之间存在显着的正相关性，NADH可能催化磷酸盐还原过程。该基因驱动的异化硫酸盐还原途径的最后阶段也可能为磷酸盐还原提供能量。 PH的迁移和转化使硫基CW中有效磷（Resin-P和NaHCO-P）从35%增加到56%，磷吸附能力提高12%。有效磷比例较高，植物对磷的吸收率提高了 17%。这项研究提高了对硫基化学武器中磷循环的认识，并为化学武器的长期稳定运行提供了新的见解。