This study systematically investigated the effects of temperature changes on the degradation of antibiotics in soil, as well as the alterations in microbial community structure and aggregation, through a field warming experiment in a greenhouse. Compared to non-warming soil, the warming treatment significantly accelerated the degradation rate of tetracyclines during soil freezing and mitigated the impact of environmental fluctuations on soil microbial communities. The greenhouse environment promoted the growth and reproduction of a wide range of microbial taxa, but the abundance of Myxococcota was positively correlated with antibiotic concentrations in both treatments, suggesting a potential specific association with antibiotic degradation processes. Long-term warming in the greenhouse led to a shift in the assembly process of soil microbial communities, with a decrease in dispersal limitation and an increase in the drift process. Furthermore, co-occurrence network analysis revealed a more loosely structured microbial community in the greenhouse soil, along with the emergence of new characteristic taxa. Notably, more than 60% of the key taxa that connected the co-occurrence networks in both groups belonged to rare taxa, indicating that rare taxa play a crucial role in maintaining community structure and function.

The surface chemistry of biochar plays a pivotal role in the adsorption and stabilization of soil organic carbon (SOC); however, sorption-mediated mechanisms remain insufficiently understood for biochars derived from invasive plants. In this study, Solanum rostratum biomass, an aggressive invasive weed in northern China, was pyrolyzed at 400–600 °C in 2023 to produce biochars with varying surface functionalities and structural features. FTIR, Raman, XPS, and SEM analyses revealed that increasing pyrolysis temperature led to decreased oxygen-containing functional groups and enhanced aromatic condensation, reflecting a transition from hydrogen bonding to π–π and hydrophobic sorption mechanisms. Soil incubation experiments using sandy loam soil showed that biochar produced at 500 °C significantly increased the stable carbon pool (SCP) to 52.4%, compared to 30.6% in unamended soils. It also reduced cumulative CO₂ release from 1.74 mg g⁻¹ to 1.21 mg g⁻¹ soil, indicating improved carbon retention. Bacterial 16S rRNA gene sequencing revealed that biochar amendments significantly altered community composition and increased deterministic assembly, particularly under 500 °C biochar, suggesting a sorption-driven niche filtering effect. These findings demonstrate that S. rostratum-derived biochar, especially at intermediate pyrolysis temperatures, enhances both carbon sequestration and microbial habitat structure. This has direct implications for improving degraded soils in arid farming regions, offering a dual strategy for invasive biomass management and climate-resilient agriculture.

The dissemination of antibiotic resistance genes (ARGs) in paddy ecosystems poses a serious threat to environmental health. A pot experiment was conducted to assess the efficacy of alkyl glycoside-stabilized selenium nanoparticles (AG-SeNPs) in mitigating ARG abundance within the soil, phyllosphere, and rice grains. Functional prediction, null model analysis, variance partitioning, and structural equation modeling were employed to identify ARG hosts, key metabolic pathways, and environmental drivers of ARG dynamics. Results showed that foliar application of AG-SeNPs (30 g ha ⁻¹ ) reduced ARGs by 5.13 × 10 ⁶ copies g ⁻¹ , 2.28 × 10 ⁷ copies g ⁻¹ , and 1.25 × 10 ⁶ copies g ⁻¹ in the rhizosphere soil, phyllosphere, and grains, respectively. TetPA and tetGF were dominant ARGs, predominantly associated with Mariniphaga anaerophila , Sediminibacter magnilacihabitans , and Limnospira fusiformis . ARG attenuation was linked to enhanced ABC transporter activity and suppressed purine metabolism and ribosome function, thereby reducing intracellular antibiotic pressure and limiting ARG expression in soil microbes. In the phyllosphere, activation of two-component systems modulated stress responses and antimicrobial resistance pathways, constraining horizontal gene transfer. Nano-selenium increased heterogeneous selection in the phyllosphere, enhancing deterministic filtering of ARG hosts and restructuring microbial communities. Environmental factors explained 42.81% of ARG variation, wherein selenium accumulation in leaves directly reduced ARG abundance, and soil pH, electrical conductivity, and organic matter indirectly influenced ARG dynamics through microbial community restructuring. These findings highlight that AG-SeNPs mitigate ARGs through an environmentally mediated, microbially driven cascade, offering a promising strategy for antibiotic resistance control in agricultural systems. IMPORTANCE: The dissemination of antibiotic resistance genes within agricultural soil-plant systems poses a severe threat to food safety and public health. This study demonstrates that foliar application of nano-selenium fertilizer effectively reduces ARG abundance in the soil, phyllosphere, and rice grains. We found that nano-selenium functions not by direct bactericidal action but by beneficially reshaping the microbial communities in both the leaves and soil, thereby suppressing the pathways for ARG transmission. Our findings provide a novel and sustainable strategy to mitigate antibiotic resistance in agricultural ecosystems, potentially reducing the risk of these genes entering the human food chain via rice.