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111.

Animal manure is an important source of antibiotics and antibiotic resistance genes (ARGs) in the environment. However, the difference of antibiotic residues and ARG profiles in layer and broiler manure as well as their compost remains unexplored. In this study, we investigated the profiles of twelve antibiotics, seventeen ARGs, and class 1 integrase gene (intI1) in layer and broiler manure, and the corresponding compost at large-scale. Compared with layer manure, broiler manure exhibited approximately six times more residual tetracyclines, especially chlortetracycline. The relative abundances of qnrS and ermA genes in broiler manure were significantly higher than those in layer manure. The concentration of tetracyclines not only had a significantly positive correlation with tetracycline resistance genes (tetA and tetC) but was also positively correlated with quinolone resistance (qepA, qnrB, and qnrS) and macrolide resistance (ermA and ermT). Most ARGs in manure were reduced after composting. However, the relative abundance of sulfonamide resistance gene sul1 increased up to 2.41% after composting, which was significantly higher than that of broiler (0.41%) and layer (0.62%) manure. The associated bacterial community was characterized by high-throughput 16S rRNA gene sequencing. The relative abundances of thermophilic bacteria had significant positive correlations with the abundance of sul1 in compost. The composting has a significant impact on the ARG-associated gut microbes in poultry manure. Variation partitioning analysis indicated that the change of bacterial community compositions and antibiotics contributed partially to the shift in ARG profiles. The results indicate that at industry-scale production broiler manure had more antibiotics and ARGs than layer manure did, and composting decreased most ARG abundances in poultry manure except for sulfonamide resistance genes.

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112.
Environmental Science and Pollution Research - In this work, the Ni-doped anatase TiO2 single crystals loaded on activated carbon (Ni-T/AC) were synthesized by a sol–gel method. The chemical...  相似文献   
113.
Environmental Science and Pollution Research - Aerobic denitrifiers have the potential to reduce nitrate in polluted water under aerobic conditions. A salt-tolerant aerobic denitrifier was newly...  相似文献   
114.
Environmental Science and Pollution Research - Longchun 30, a new wheat variety, was used to investigate seedling growth, element absorption, and antioxidant response under 150 mM NaCl and tea...  相似文献   
115.
Environmental Science and Pollution Research - Municipal solid waste (MSW) incineration power generation is an important treatment technology, which has been widely concerned in recent years. It is...  相似文献   
116.
Environmental Science and Pollution Research - Polycyclic aromatic hydrocarbons (PAHs), as a class of important environmental pollutants, have received considerable concern due to their widespread...  相似文献   
117.
Environmental Science and Pollution Research - In the process of coal gangue surface accumulation and underground filling disposal, the heavy metals contained in coal gangue will inevitably...  相似文献   
118.
南京北郊黑碳气溶胶的来源解析   总被引:4,自引:4,他引:0  
利用七波段黑碳仪对2015年1~12月南京北郊地区黑碳(black carbon,BC)气溶胶实时监测,并结合黑碳仪模型对该期间内BC进行来源解析,探讨化石燃料排放产生BC(BCff)与生物质燃烧产生BC(BCbb)各自的贡献大小.结果表明,观测期间BC的吸收波长指数(α)和生物质燃烧对BC的贡献百分比(BB)的变化范围都较大但趋势较为一致;冬季α值偏高而夏季α值较低,表明不同季节时间BC来源和强度的差异性.BCff在各季节BC总浓度中占比略有不同但均高于75%;BC、BCff和BCbb的日变化趋势均呈双峰特征,在07:00~09:00和18:00~21:00左右浓度有最大值;全天中,BCff对BC贡献最大,浓度值约为BCbb的3~5倍;夜晚BC浓度普遍高于白天,其平均浓度值是白天的1.2倍.由浓度权重轨迹分析的结果可知,影响南京北郊地区高浓度BC的源区主要集中在浙江、安徽以及江西和福建等地区.  相似文献   
119.
J市饮用水氯消毒副产物分析及其健康风险评价   总被引:7,自引:7,他引:0  
J市位于太湖下游,其水源水质受上游和自身工农业发展的影响,有机物和氨氮浓度较高,氯消毒副产物及其引发的健康风险广泛受到关注.2012年5、8、10月以及2013年1月采样,使用气相色谱法分析了J市饮用水中4种三卤甲烷和5种卤乙酸的含量,发现自来水中三卤甲烷浓度占三卤甲烷与卤乙酸总和的88.1%以上,5月、8月和次年1月浓度较高(分别为39.34、50.37和28.02μg.L-1),10月浓度(19.19μg.L-1)较低,远高于卤乙酸的浓度(2.58~4.02μg.L-1).自来水煮沸3min后,三卤甲烷可去除92.3%以上,但卤乙酸会大幅度增加.基于EPA推荐的健康风险评价模型对经口摄取途径时氯消毒副产物的致癌和非致癌风险进行计算,发现化学致癌物质的健康风险为3.1×10-6~7.3×10-6,高于可接受风险水平1×10-6;煮沸后致癌物质的健康风险大幅度降低至7.9×10-7,低于可接受风险水平.煮沸后非致癌氯消毒副产物的健康风险由2.1×10-11显著升高至3.4×10-9,未超过10-5的风险管理参考值.  相似文献   
120.
In this study, a lab-scale biological anaerobic/anaerobic/anoxic/membrane bioreactor(A_-~3MBR) was designed to treat wastewater from the ethanol fermentation of food waste,a promising way for the disposal of food waste and reclamation of resources. The 454 pyrosequencing technique was used to investigate the composition of the microbial community in the treatment system. The system yielded a stable effluent concentration of chemical oxygen demand(202 ± 23 mg/L), total nitrogen(62.1 ± 7.1 mg/L), ammonia(0.3 ±0.13 mg/L) and total phosphorus(8.3 ± 0.9 mg/L), and the reactors played different roles in specific pollutant removal. The exploration of the microbial community in the system revealed that:(1) the microbial diversity of anaerobic reactors A_1 and A_2, in which organic pollutants were massively degraded, was much higher than that in anoxic A_3 and aerobic MBR;(2) although the community composition in each reactor was quite different, bacteria assigned to the classes Clostridia, Bacteroidia, and Synergistia were important and common microorganisms for organic pollutant degradation in the anaerobic units, and bacteria from Alphaproteobacteria and Betaproteobacteria were the dominant microbial population in A_3 and MBR;(3) the taxon identification indicated that Arcobacter in the anaerobic reactors and Thauera in the anoxic reactor were two representative genera in the biological process. Our results proved that the biological A_-~3MBR process is an alternative technique for treating wastewater from food waste.  相似文献   
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