Introduction: This study aimed to assess the influence of experimental warming and fertilization on rice yield and paddy methane emissions. Methods: A free-air temperature increase system was used for the experimental warming treatment (ET), while the control treatment used ambient temperature (AC). Each treatment contained two fertilization strategies, (i) normal fertilization with N, P and K fertilizers (CN) and (ii) without N fertilizer input (CK). Results: The yield was remarkably dictated by fertilization (p < 0.01), but not warming. Its value with CN treatment increased by 76.24% compared to CK. Also, the interactive effect of warming and fertilization on CH₄ emissions was insignificant. The seasonal emissions from warming increased by 36.93% compared to AC, while the values under CN treatment increased by 79.92% compared to CK. Accordingly, the ET-CN treatment obtained the highest CH₄ emissions (178.08 kg ha⁻¹), notably higher than the other treatments. Also, the results showed that soil fertility is the main driver affecting CH₄ emissions rather than soil microorganisms. Conclusions: Fertilization aggravates the increasing effect of warming on paddy methane emissions. It is a daunting task to optimize fertilization to ensure yield and reduce methane emissions amid global warming.

Soy products are among the most common sources of protein, and large volumes of wastewater are produced from legume processing. In this study, the Priestia aryabhattai FM5 strain, isolated from soil, was found to be capable of nitrogen assimilation. The NH₄⁺ and NO₃⁻ removal characteristics of P. aryabhattai FM5 were investigated to better understand its removal capability. The optimal conditions for NH₄⁺ removal were pH 8.0, temperature—25 °C, and C/N ratio—20, with sodium succinate as the carbon source. Under the conditions of pH 7.0, temperature—35 °C, and C/N ratio—10, with sodium acetate as the carbon source, strain FM5 reached the highest NO₃⁻ removal efficiency. The genome of FM5 revealed genes involved in assimilatory nitrate reduction and glutamate metabolism, such as nasA, nirA, nrt, glnA, gltB/D, and gdhA. When cultured in wastewater from soymilk processing with activated carbon for 72 h (h), the NH₄⁺ concentration and chemical oxygen demand (COD) decreased from 29.5 to 4.8 mg·L⁻¹ and 2058.3 mg·L⁻¹ to 295.3 mg·L⁻¹, respectively. This study provides deeper insights into the NH₄⁺ and NO₃⁻ removal-capable bacterial strain FM5 and improves the application of Priestia in wastewater.