RESUMEN
The massive use of antibiotics has led to the escalation of microbial resistance in aquatic environment, resulting in an increasing concern regarding antibiotic resistance genes (ARGs), posing a serious threat to ecological safety and human health. In this study, surface water samples were collected at eight sampling sites along the Yangtze River Estuary. The seasonal and spatial distribution patterns of 10 antibiotics and target genes in two major classes (sulfonamides and tetracyclines) were analyzed. The findings indicated a high prevalence of sulfonamide and tetracycline resistance genes along the Yangtze River Estuary. Kruskal-Wallis analysis revealed significant seasonal variations in the abundance of all target genes. The accumulation of antibiotic resistance genes in the coastal area of the Yangtze River Estuary can be attributed to the influence of urban instream runoff and the discharge of effluents from wastewater treatment plants. ANISOM analysis indicated significant seasonal differences in the microbial community structure. VPA showed that environmental factors contribute the most to ARG variation. PLS-PM demonstrate that environmental factors and microbial communities pose direct effect to ARG variation. Analysis of driving factors influencing ARGs in this study may shed new insights into the mechanism of the maintenance and propagation of ARGs.
Asunto(s)
Farmacorresistencia Microbiana , Estuarios , Ríos , Ríos/microbiología , Farmacorresistencia Microbiana/genética , China , Monitoreo del Ambiente , Antibacterianos/farmacología , Genes Bacterianos , Estaciones del AñoRESUMEN
In this paper, water and sediments were sampled at eight monitoring stations in the coastal areas of the Yangtze River Estuary in summer and autumn 2021. Two sulfonamide resistance genes (sul1 and sul2), six tetracycline resistance genes (tetM, tetC, tetX, tetA, tetO, and tetQ), one integrase gene (intI1), 16 S rRNA genes, and microbial communities were examined and analyzed. Most resistance genes showed relatively higher abundance in summer and lower abundance in autumn. One-way analysis of variance (ANOVA) showed significant seasonal variation of some ARGs (7 ARGs in water and 6 ARGs in sediment). River runoff and WWTPs are proven to be the major sources of resistance genes along the Yangtze River Estuary. Significant and positive correlations between intI1 and other ARGs were found in water samples (P < 0.05), implying that intI1 may influence the spread and propagation of resistance genes in aquatic environments. Proteobacteria was the dominant phylum along the Yangtze River Estuary, with an average proportion of 41.7%. Redundancy analysis indicated that the ARGs were greatly affected by temperature, dissolved oxygen, and pH in estuarine environments. Network analysis showed that Proteobacteria and Cyanobacteria were the potential host phyla for ARGs in the coastal areas of the Yangtze River Estuary.
Asunto(s)
Estuarios , Microbiota , Resistencia a la Tetraciclina/genética , Ríos/microbiología , Genes Bacterianos , Farmacorresistencia Microbiana/genética , Antibacterianos/análisis , Tetraciclina/análisis , Sulfanilamida , Sulfonamidas/análisis , Agua/análisis , Microbiota/genética , China , Monitoreo del AmbienteRESUMEN
Due to the extensive use of antibiotics, the resistance of microorganisms to antibiotics in the environment is increasing, and the problem of antibiotic resistance genes (ARGs) is becoming more and more severe, which seriously threatens ecological security and human health. In order to study the distribution characteristics of ARGs and the microbial community in different media in the coastal area of the Yangtze River Estuary, water and sediment samples from eight sites were collected through a field investigation. Two sulfonamide resistance genes ([STBX]sul1, sul2[STBZ]) and six tetracycline resistance genes (tetM, tetC, tetX, tetA, tetO, and tetQ), one integrase gene intI[STBX]1[STBZ], 16S rRNA gene, and the microbial community were detected and analyzed. The results showed that the detection rate of 10 resistance genes in the coastal area of the Yangtze River Estuary was 100%. [STBX]intI1[STBZ] was significantly positively correlated with various ARGs in the water samples. Proteobacteria and Bacteroidota were the dominant bacteria phyla in the water environment of the Yangtze River Estuary. Chloroplast was the main bacteria genus in water, and Chloroplast and Nitrospira were the main bacteria genera in sediment. In water, Nitrospirota was the common potential host of four tetracycline resistance genes (tetX, tetA, tetO, and tetQ). In sediments, Sva0485 was a potential host community shared by [STBX]sul1 and intI1[STBZ]. The distribution of the microbial community was an important factor affecting the migration and transformation of ARGs in the nearshore area of the Yangtze River Estuary.
Asunto(s)
Antibacterianos , Microbiota , Humanos , Antibacterianos/análisis , Genes Bacterianos , Ríos , Estuarios , ARN Ribosómico 16S/genética , Bacterias/genética , Tetraciclina , Farmacorresistencia Microbiana/genética , Agua , ChinaRESUMEN
Mining operations lead to the production of large quantities of mineral waste, such as fluid fine tailings whose disposal is rather challenging. In Brazil, tailings disposal is facing a critical situation due to the large accidents that took place in the last couple of years. As a response to these accidents, the Brazilian Mining Agency became stricter on licensing mining complexes and issued an interruption on activities on 56 tailings dams. In this paper, the authors propose a promising approach to minimize risks on the existing tailings dams hoping that the industry succeeds at mining avoiding social harms and environmental damages. The results presented herein showed that in situ electrical dewatering is a promising technology that offers many benefits. It can significantly increase the solids content of liquefiable tailings stratum within a short time. This leads to tailings masses possessing higher shear strength. As a consequence, this technology might well lead to safe tailing dams in Brazil bringing socio-economic and environmental benefits.