High-throughput profiling the effects of zinc on antibiotic resistance genes in the anaerobic digestion of swine manure. - Related Documents




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704401.0000High-throughput profiling the effects of zinc on antibiotic resistance genes in the anaerobic digestion of swine manure. The problem of antibiotic resistance genes (ARGs) caused by heavy metals has attracted extensive attention of human beings. Zn, a widely used feed additive, has a very high residue in swine manure, but the distribution characteristics of ARGs imposed by Zn in anaerobic digestion (AD) products are not clear. In this study, the behaviour of mobile genetic elements (MGEs), bacterial community, and their association with ARGs were determined in the presence of 125 and 1250 mg L(-1) Zn in AD system of swine manure. Zn-treated enriched the abundance of ARGs, and produced some new genotypes that were not detected in CK treatment. In addition, low concentration of Zn significantly increased the relative abundance of ARGs, as compared to higher Zn and CK group. Correspondingly, the abundances of most top30 genus were highest in ZnL (125 mg L(-1) Zn), followed by CK and ZnH (1250 mg L(-1) Zn). Notably, network analysis showed that the relationship between ARGs and MGEs is closer than that ARGs and bacteria, suggesting that ARGs increased in Zn-treated, especially low level Zn, may be due to the amplification transfer of ARGs among varied microorganisms by horizontal transfer with MGEs. Therefore, strengthen the management of in livestock manure is crucial to control the spread of ARGs in organic fertilizers.202437193677
704310.9999Antibiotic resistance gene transfer during anaerobic digestion with added copper: Important roles of mobile genetic elements. The abuse of heavy metals as feed additives in livestock is widespread and it might aggravate the spread of antibiotic resistance genes (ARGs) in the environment. However, the mechanisms that allow heavy metals to increase the transmission of ARGs in the environment remain unclear. Cu is the heavy metal present at the highest concentration in livestock manure, and thus Cu was selected to investigate the responses of ARGs to heavy metals. The effects of the microbial communities, mobile genetic elements (MGEs), and heavy metal resistance genes (HMRGs) on ARGs were determined in the presence of 75 and 227 mg L(-1) Cu in a swine manure anaerobic digestion (AD) system. In the AD products, the presence of residual Cu (75 and 227 mg L(-1)) increased the total ARGs, HMRGs, and some MGEs, and the higher Cu selected more ARGs than the lower Cu treatment. The results demonstrated that Cu could promote the co-selection of HMRGs, ARGs, and MGEs. The different levels of Cu did not change the bacterial community composition, but they influenced the abundances of bacteria during AD. Network analysis showed that the presence of Cu increased the co-occurrence of specific bacteria containing ARGs, HMRGs, and MGEs. Furthermore, the co-occurrence of MGEs and ARGs increased greatly compared with that of HMRGs and ARGs. Therefore, compared HMRGs, the increased MGEs had the main effect on increasing of ARGs.202032659562
704220.9998Response of antibiotic resistance genes abundance by graphene oxide during the anaerobic digestion of swine manure with copper pollution. The pollution of various environments with antibiotic resistance genes (ARGs) is an urgent problem that needs to be addressed, especially in heavy metal-polluted environments. This study investigated the responses of ARGs and mobile genetic elements (MGEs) to the addition of graphene oxide (GO) to swine manure containing a high concentration copper during anaerobic digestion. The total copy numbers of ARGs and MGEs were significantly enhanced by the pressure due to Cu. GO significantly decreased the ARG and MGE copy numbers, where the low GO concentration performed better than the high GO concentration. Network analysis showed that most of the ARGs and MGEs co-occurred and they shared the same major potential host bacteria. The contributions of different factors to ARG abundances were assessed by redundancy analysis and MGEs had the most important effect on the fate of ARGs. Thus, GO may reduce the abundance of ARGs mainly by removing MGEs.201930445329
703730.9998Impacts of cadmium addition on the alteration of microbial community and transport of antibiotic resistance genes in oxytetracycline contaminated soil. The large-scale development in livestock feed industry has increased the chances of antibiotics and heavy metals contamination in the soil. The fate of antibiotic resistance genes (ARGs) and microbial community in heavy metals and antibiotic contaminated soil is still unclear. In this study, we investigated the effect of cadmium (Cd) addition on the transport of ARGs, microbial community and human pathogenic bacteria in oxytetracycline (OTC) contaminated soil. Results showed that the addition of OTC significantly increased the abundance of ARGs and intI1 in the soil and lettuce tissues. The addition of Cd to OTC treated soil further increased the abundance and translocation of ARGs and intI1. Moreover, Cd promoted the transfer of potential human pathogenic bacteria (HPB) into lettuce tissues. Compared with O10 treatment, the addition of Cd decreased the concentration of OTC in soil and lettuce tissue, but slightly increased the fresh weight of lettuce tissues. Redundancy analysis indicated that bacterial community succession is a major factor in ARGs variation. Network analysis indicated that the main host bacteria of ARGs were mainly derived from Proteobacteria. Correlation analysis showed that intI1 was significantly correlated with tetG, tetC, sul1, sul2, ermX, and ermQ. Meanwhile, potential HPB (Clostridium, and Burkholderia) was significantly correlated with intI1 and eight ARGs (tetG, tetC, tetW, tetX, sul1, sul2, ermX, and ermQ.). The findings of this study suggest that the addition of heavy metals to agricultural fields must be considered in order to reduce the transfer of ARGs in the soil and crops.202133183716
695040.9998Ceftiofur in swine manure contributes to reducing pathogens and antibiotic resistance genes during composting. Aerobic composting is a common way for the disposal of feces produced in animal husbandry, and can reduce the release of antibiotic resistance genes (ARGs) from feces into the environment. In this study, we collected samples from two distinct treatments of swine manure compost with and without ceftiofur (CEF), and identified the ARGs, mobile genetic elements (MGEs), and bacterial community by metagenomic sequencing. The impacts of CEF on the bacterial community composition and fate of ARGs and MGEs were investigated. With increasing composting temperature and pH, the concentration of CEF in the manure decreased rapidly, with a degradation half-life of 1.12 d and a 100% removal rate after 10 d of aerobic composting. Metagenomics demonstrated that CEF in the manure might inhibit the growth of Firmicutes and Proteobacteria, thereby reducing some ARGs and MGEs hosted by these two bacteria, which was further confirmed by the variations of ARGs and MGEs. A further redundancy analysis suggested that pH and temperature are key environmental factors affecting ARG removal during composting, and intI1 and bacterial communities also have significant influence on ARG abundance. These results are of great significance for promoting the removal of some ARGs from animal manure by controlling some key environmental factors and the type of antibiotics used in animals.202438685300
704050.9998The maturity period is the main stage of antibiotic resistance genes reduction in aerobic composting process of swine manure in sub-scale farms. This study was focused on the changes of antibiotic resistance genes (ARGs) and their potential host bacteria during the swine manure composting on sub-scale farms. Eight target ARGs increased 427% on average, with a trend of increase at early stage and decrease at later stage, and the main reduction stage appeared in maturity stage. The abundance of ARGs was mainly affected by the community succession of potential host bacteria. Composting could reduce the abundance of potential host bacteria of ARGs as well as pathogens such as Pseudomonas, and reduce the environmental risks of swine manure. N/C and S levels had a positive effect on the potential host of most ARGs. Prolonging the maturity period would inhibit the growth of potential host bacteria of ARGs during composting, therefore inhibiting the transmission of ARGs.202132971337
809160.9998Changes in antibiotic resistance genes and mobile genetic elements during cattle manure composting after inoculation with Bacillus subtilis. This study explored the effects of Bacillus subtilis at four levels (0, 0.5%, 1%, and 2% w/w compost) on the variations in ARGs, mobile genetic elements (MGEs), and the bacterial community during composting. The composting process had a greater impact on ARGs than Bacillus subtilis. The main ARG detected was sul1. The addition of Bacillus subtilis at 0.5% reduced the relative abundances of ARGs, MGEs, and human pathogenic bacteria (by 2-3 logs) in the mature products. Network and redundancy analyses suggested that intI1, Firmicutes, and pH were mainly responsible for the changes in ARGs, thus controlling these factors might help to inhibit the spread of ARGs.201931442833
807670.9998Effects of chlortetracycline and copper on tetracyclines and copper resistance genes and microbial community during swine manure anaerobic digestion. As antibiotic and heavy metals are over used in the livestock industry, animal manure is a reservoir of antibiotic resistance genes (ARGs). Anaerobic digestion has been reported to have the potential to reduce ARGs. However, few studies investigated whether reduction of ARGs would be affected by different external pressures including antibiotics and heavy metals during anaerobic digestion. The purpose of this study was thus to investigate effects of both chlortetracycline (CTC) and Cu on reduction of ARGs, heavy metal resistance genes (HMRGs) and mobile genetic elements (MGEs) during the swine manure anaerobic digestion. The results showed that the predominant ARGs (tetO, tetW, tetX, tetL) could be effectively reduced (approximately 1.00 log copies/g TS) through mesophilic anaerobic digestion. Microbial community evolution was the main driver. It was interesting that Treponema might indicate the termination of anaerobic digestion and compete with ARGs host bacteria. Addition of CTC, Cu and CTC+Cu affected microbial community change and hindered removal of ARGs, especially, CTC+Cu seriously affected Treponema and ARGs during anaerobic digestion.201728432950
807980.9998Response of antibiotic resistance to the co-exposure of sulfamethoxazole and copper during swine manure composting. Heavy metals driven co-selection of antibiotic resistance in soil and water bodies has been widely concerned, but the response of antibiotic resistance to co-existence of antibiotics and heavy metals in composting system is still unknown. Commonly used sulfamethoxazole and copper were individually and jointly added into four reactors to explore their effects on antibiotic resistance genes (ARGs), mobile genetic elements (MGEs), heavy metal resistance genes (MRGs) and bacterial community structure. The abundance of total ARGs and MGEs were notably decreased by 68.64%-84.95% and 91.27-97.38%, respectively, after the composting. Individual addition of sulfamethoxazole, individual addition of copper, simultaneously addition of sulfamethoxazole and copper increased the abundance of ARGs and MGEs throughout the composting period. Co-exposure of sulfamethoxazole and copper elevated the total abundance of ARGs by 1.17-1.51 times by the end of the composting compared to individual addition of sulfamethoxazole or copper. Network analysis indicated that the shifts in potential host bacteria determined the ARGs variation. Additionally, MGEs and MRGs had significant effects on ARGs, revealing that horizontal gene transfer and heavy metals induced co-resistance could promote ARGs dissemination.202234537705
704190.9998Antibiotic and heavy metal resistance genes in sewage sludge survive during aerobic composting. Municipal sewage sludge has been generated in increasing amounts with the acceleration of urbanization and economic development. The nutrient rich sewage sludge can be recycled by composting that has a great potential to produce stabilized organic fertilizer and substrate for plant cultivation. However, little is known about the metals, pathogens and antibiotic resistance transfer risks involved in applying the composted sludge in agriculture. We studied changes in and relationships between heavy metal contents, microbial communities, and antibiotic resistance genes (ARGs), heavy metal resistance genes (HMRGs) and mobile genetic elements (MGEs) in aerobic composting of sewage sludge. The contents of most of the analyzed heavy metals were not lower after composting. The bacterial α-diversity was lower, and the community composition was different after composting. Firmicutes were enriched, and Proteobacteria and potential pathogens in the genera Arcobacter and Acinetobacter were depleted in the composted sludge. The differences in bacteria were possibly due to the high temperature phase during the composting which was likely to affect temperature-sensitive bacteria. The number of detected ARGs, HMRGs and MGEs was lower, and the relative abundances of several resistance genes were lower after composting. However, the abundance of seven ARGs and six HMRGs remained on the same level after composting. Co-occurrence analysis of bacterial taxa and the genes suggested that the ARGs may spread via horizontal gene transfer during composting. In summary, even though aerobic composting is effective for managing sewage sludge and to decrease the relative abundance of potential pathogens, ARGs and HMRGs, it might include a potential risk for the dissemination of ARGs in the environment.202336608829
6999100.9998Different impacts of manure and chemical fertilizers on bacterial community structure and antibiotic resistance genes in arable soils. Both manure and chemical fertilizers are widely used in modern agriculture. However, the impacts of different fertilizers on bacterial community structure and antibiotic resistance genes (ARGs) in arable soils still remain unclear. In this study, high-throughput sequencing and quantitative PCR were employed to investigate the bacterial community structure, ARGs and mobile genetic elements (MGEs) influenced by the application of different fertilizers, including chemical fertilizers, piggery manure and straw ash. The results showed that the application of fertilizers could significantly change the soil bacterial community and the abundance of Gaiella under phylum Actinobacteria was significantly reduced from 12.9% in unfertilized soil to 4.1%-7.4% in fertilized soil (P < 0.05). It was also found that the application of manure could cause a transient effect on soil resistome composition and the relative abundance of ARGs increased from 7.37 ppm to 32.10 ppm. The abundance of aminoglycoside, sulfonamide and tetracycline resistance genes greatly increased after manure fertilization and then gradually returned to normal levels with the decay of some intestinal bacteria carrying ARGs. In contrast, the application of chemical fertilizers and straw ash significantly changed the bacterial community structure but exerted little effect on soil resistome. Overall, the results of this study illustrated the different effects of different fertilizers on the soil resistome and revealed that the changes of soil resistome induced by manure application mainly resulted from alteration of bacteria community rather than the horizontal gene transfer.201728898777
6948110.9998Fate of antibiotic resistance genes and metal resistance genes during the thermophilic fermentation of solid and liquid swine manures in an ectopic fermentation system. Environmental pollution due to resistance genes from livestock manure has become a serious issue that needs to be resolved. However, little studies focused on the removal of resistance genes in simultaneous processing of livestock feces and urine. This study investigated the fate of antibiotic resistance genes (ARGs), metal resistance genes (MRGs), and class 1 integron-integrase gene (intI1) during thermophilic fermentation of swine manure in an ectopic fermentation system (EFS), which has been regarded as a novel system for efficiently treating both feces and urine. The abundances of MRGs and tetracycline resistance genes were 34.44-97.71% lower in the EFS. The supplementation of heavy metals significantly increased the abundance of intI1, with the enhancement effect of copper being more prominent than that of zinc. The highest abundances of resistance genes and intI1 were observed at high Cu levels (A2), indicating that Cu can increase the spreading of resistance genes through integrons. Network analysis revealed the co-occurrence of ARGs, MRGs, and intI1, and these genes potentially shared the same host bacteria. Redundancy analysis showed that the bacterial community explained most of the variations in ARGs, and environmental factors had influences on ARGs abundances by modulating the bacterial community composition. The decreased Sphingomonas, Comamonas, Acinetobacter, Lactobacillus, Bartonella, Rhizobium, and Bacteroides were mainly responsible for the reduced resistance genes. These results demonstrate that EFS can reduce resistance genes in simultaneous processing of livestock feces and urine.202133592372
6949120.9998Tracing the transfer characteristics of antibiotic resistance genes from swine manure to biogas residue and then to soil. Based on laboratory simulation experiments and metagenomic analysis, this study tracked the transmission of antibiotic resistance genes (ARGs) from swine manure (SM) to biogas residue and then to soil (biogas residue as organic fertilizer (OF) application). ARGs were abundant in SM and they were assigned to 11 categories of antibiotics. Among the 383 ARG subtypes in SM, 43 % ARG subtypes were absent after anaerobic digestion (AD), which avoided the transfer of these ARGs from SM to soil. Furthermore, 9 % of the ARG subtypes in SM were introduced into soil after amendment with OF. Moreover, 43 % of the ARG subtypes in SM were present in OF and soil, and their abundances increased slightly in the soil amended with OF. The bacterial community in the soil treated with OF was restored to its original state within 60 to 90 days, probably because the abundances of ARGs were elevated but not significantly in the soil. Network analysis identified 31 potential co-host bacteria of ARGs based on the relationships between the bacteria community members, where they mainly belonged to Firmicutes, followed by Bacteroidetes, Actinobacteria, and Proteobacteria. This study provides a basis for objectively evaluating pollution by ARGs in livestock manure for agricultural use.202438072280
7039130.9998Profiles and key drivers of bacteria/phage co-mediated antibiotic resistance genes during swine manure composting amended with humic acid. Phages can promote the spread of antibiotic resistance genes (ARGs) in agricultural environments through transduction. However, studies on phage-mediated ARG profiles during composting have not been performed. This study investigated the effects of adding humic acid (HA) on the abundances of bacteria/phage co-mediated ARGs (b/pARGs) during swine manure composting and the key factors that affected the transmission of b/pARGs. The results showed that the addition of 5 % HA during composting could effectively reduce the absolute abundances of b/pARGs, inhibit the proliferation of pathogenic microorganisms (e.g., Corynebacterium and Streptococcus) that carried ARGs, and ultimately affect the fate of b/pARGs in the composting process by regulating key environmental factors to change the abundance of co-host bacteria. Overall, the findings of this study provided new information for understanding the main driving factors affecting the b/pARGs profile and provided a reference for the prevention and control of ARGs pollution during composting.202336774987
8085140.9998Elevated CO(2) alleviated the dissemination of antibiotic resistance genes in sulfadiazine-contaminated soil: A free-air CO(2) enrichment study. Climate change affects soil microbial communities and their genetic exchange, and subsequently modifies the transfer of antibiotic resistance genes (ARGs) among bacteria. However, how elevated CO(2) impacts soil antibiotic resistome remains poorly characterized. Here, a free-air CO(2) enrichment system was used in the field to investigate the responses of ARGs profiles and bacterial communities to elevated CO(2) (+200 ppm) in soils amended with sulfadiazine (SDZ) at 0, 0.5 and 5 mg kg(-1). Results showed that SDZ exposure induced the co-occurrence of beta-lactamase and tetracycline resistance genes, and SDZ at 5 mg kg(-1) enhanced the abundance of aminoglycoside, sulfonamide and multidrug resistance genes. However, elevated CO(2) weakened the effects of SDZ at 0.5 mg kg(-1) following an observed reduction in the total abundance of ARGs and mobile genetic elements. Additionally, elevated CO(2) significantly decreased the abundance of vancomycin resistance genes and alleviated the stimulation of SDZ on the dissemination of aminoglycoside resistance genes. Correlation analysis and structural equation models revealed that elevated CO(2) could directly influence the spread of ARGs or impose indirect effects on ARGs by affecting soil properties and bacterial communities. Overall, our results furthered the knowledge of the dissemination risks of ARGs under future climate scenarios.202336857828
8080150.9998Fates of antibiotic resistance genes and bacterial/archaeal communities of activated sludge under stress of copper: Gradient increasing/decreasing exposure modes. Effect of copper (Cu) on antibiotic resistance genes (ARGs) and bacterial/archaeal community of activated sludge under gradient increasing (0.5-10 mg/L) or decreasing exposure (10-0.5 mg/L) modes was explored. Here, 29 genes were detected among 48 selected ARGs and mobile gene elements (MGEs). Two exposure modes showed dissimilar effects on ARGs and distribution was more affected by environmental concentrations of Cu, which promoted transmission of ARGs (multiple drug resistance and sulfonamide). Cellular protection was main resistance mechanism, which was less inhibited than efflux pumps. The tnpA-02, as main MGE, interacted closely with ARGs (sul2, floR, etc.). Gradient increasing exposure mode had more effects on bacterial/archaeal structure and composition. Bacteria were main hosts for specific ARGs and tnpA-02, while archaea carried multiple ARGs (cmx(A), adeA, etc.), and bacteria (24.24 %) contributed more to changes of ARGs than archaea (19.29 %). This study clarified the impacts of Cu on the proliferation and transmission of ARGs.202236096328
6951160.9998The vertical migration of antibiotic-resistant genes and pathogens in soil and vegetables after the application of different fertilizers. The prevalence of bacterial resistance caused by the application of animal manure has become an important environmental issue. Herein, the vertical migration of antibiotic resistance genes (ARGs) and pathogens in soil and vegetables after the application of different fertilizers was explored. The results showed that the application of composted manure considerably enhanced the abundance of most ARGs and pathogens, especially in surface soil and pakchoi roots. Moreover, the soil ARGs increased partially from log 1.93 to log 4.65 after the application of composted manure, and six pathogens were simultaneously detected. It was observed that the increase in soil depth decreased most ARGs and pathogens by log 1.04-2.24 and 53.98 %~85.54 %, respectively. This indicated that ARGs and pathogens still existed in the deep soil (80-100 cm). Moreover, total organic carbon had a significant influence on the pathogen distribution, whereas bacterial communities primarily drove the vertical migration of ARGs rather than environmental factors. Although most of the ARG-host associations observed in the surface soil were disappeared in deep soil as revealed by network analysis, some co-occurrence pattern still occurred in deep soil, suggesting that some ARGs might be carried to deep soil by their host bacteria. These results were novel in describing the vertical migration of ARGs in the environment after the application of different fertilizers, providing ideas for curbing their migration to crops.202234400159
7255170.9998Distribution of quinolone and macrolide resistance genes and their co-occurrence with heavy metal resistance genes in vegetable soils with long-term application of manure. The spread of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs) has become an increasingly serious global public health issue. This study investigated the distribution characteristics and influencing factors of ARB and ARGs in greenhouse vegetable soils with long-term application of manure. Five typical ARGs, four heavy metal resistance genes (MRGs), and two mobile genetic elements (MGEs) were quantified by real-time quantitative polymerase chain reaction (qPCR). The amount of ARB in manure-improved soil greatly exceeded that in control soil, and the bacterial resistance rate decreased significantly with increases in antibiotic concentrations. In addition, the resistance rate of ARB to enrofloxacin (ENR) was lower than that of tylosin (TYL). Real-time qPCR results showed that long-term application of manure enhanced the relative abundance of ARGs in vegetable soils, and the content and proportion of quinolone resistance genes were higher than those of macrolide resistance genes. Redundancy analysis (RDA) showed that qepA and qnrS significantly correlated with total and available amounts of Cu and Zn, highlighting that certain heavy metals can influence persistence of ARGs. Integrase gene intI1 correlated significantly with the relative abundance of qepA, qnrS, and ermF, suggesting that intI1 played an important role in the horizontal transfer of ARGs. Furthermore, there was a weakly but not significantly positive correlation between specific detected MRGs and ARGs and MGEs. The results of this study enhance understanding the potential for increasing ARGs in manure-applied soil, assessing ecological risk and reducing the spread of ARGs.202234559332
7033180.9998Environmental drivers and interaction mechanisms of heavy metal and antibiotic resistome exposed to amoxicillin during aerobic composting. The environmental accumulation and spread of antibiotic resistance pose a major threat to global health. Aerobic composting has become an important hotspot of combined pollution [e.g., antibiotic resistance genes (ARGs) and heavy metals (HMs)] in the process of centralized treatment and resource utilization of manure. However, the interaction mechanisms and environmental drivers of HMs resistome (MRGs), antibiotic resistance (genotype and phenotype), and microbiome during aerobic composting under the widely used amoxicillin (AMX) selection pressure are still poorly understood. Here, we investigated the dynamics of HMs bioavailability and their MRGs, AMX-resistant bacteria (ARB) and antibiotic resistome (ARGs and intI1), and bacterial community to decipher the impact mechanism of AMX by conducting aerobic composting experiments. We detected higher exchangeable HMs and MRGs in the AMX group than the control group, especially for the czrC gene, indicating that AMX exposure may inhibit HMs passivation and promote some MRGs. The presence of AMX significantly altered bacterial community composition and AMX-resistant and -sensitive bacterial structures, elevating antibiotic resistome and its potential transmission risks, in which the proportions of ARB and intI1 were greatly increased to 148- and 11.6-fold compared to the control group. Proteobacteria and Actinobacteria were significant biomarkers of AMX exposure and may be critical in promoting bacterial resistance development. S0134_terrestrial_group was significantly negatively correlated with bla(TEM) and czrC genes, which might play a role in the elimination of some ARGs and MRGs. Except for the basic physicochemical (MC, C/N, and pH) and nutritional indicators (NO(3) (-)-N, NH(4) (+)-N), Bio-Cu may be an important environmental driver regulating bacterial resistance during composting. These findings suggested the importance of the interaction mechanism of combined pollution and its synergistic treatment during aerobic composting need to be emphasized.202236687604
8099190.9998The fate of antibiotic resistance genes during co-composting of swine manure with cauliflower and corn straw. Composting is not completely effective in reducing antibiotic resistance genes (ARGs) in animal manure. This work studied the effects of different treatment conditions on the fate of ARGs in composting swine manure with cauliflower and corn straw as bulking agents. The results showed that the addition of microbial agents or the ratio of corn stalks to cauliflower (1:12) could significantly decrease the absolute abundances of most ARGs (an average of 480 times) compared with the control treatment. Principal component analysis indicated that bacterial communities were significantly correlated with ARG abundance, suggesting that microbial communities have an impact on ARG variation during co-composting. Redundancy and Network analysis confirmed the changing patterns of individual ARGs (qnrS, bla(AmpC), bla(TEM-1)) were influenced by the selectivity of host bacteria (Pseudomonas, Klebsiella, and Halocella) and environmental variables (TN, NH(3)-N, TOC, and pH). These findings helped to optimize composting conditions, thereby reducing the risk of ARGs spread.202031891854