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The different metals were ranked according to their weight effect sizes (ES+) in the following order Cd > Pb > Hg > Zn > As > Cu > Ni > Cr. Metal mining in both Sichuan and Yunnan led to higher effect sizes of soil Cd (ES+Sichuan=4.16, ES+Yunnan=3.20) and Pb (ES+Sichuan=3.47, ES+Yunnan=2.54) than those of the other heavy metals, while metal mining in Guizhou led to a higher effect size of soil Hg (ES+=2.80). The effect size of metal mining on soil heavy metals was higher in cultivated soil (ES+=1.42) than in forested soil (ES+=0.50). The mining of lead-zinc and tin significantly increased the concentrations of soil Cd, Pb, and Zn, and the mining of copper significantly increased the concentrations of soil Cu, Cd, and Pb. Of the investigated soil heavy metals in Southwest China, Pb and Zn showed slight potential publication biases (P less then 0.05). The above results can provide more effective information for the environmental protection of soil in metal mining areas of Southwest China.In this study, domestic sewage was used to inoculate mature short-cut nitrification denitrifying phosphorus removal particles, which were cultivated and matured under artificial water. The operation of the short-cut nitrification denitrifying phosphorus removal system was optimized using different aerobic/anoxic durations combined with zoned sludge discharge. The results showed that regulating the aerobic/anoxic duration, in combination with zoned sludge discharge, can realize the stable operation of the system. In the later stable period, the effluent COD concentration was below 50 mg·L-1, the effluent TN concentration was below 15 mg·L-1, the TN removal rate reached about 83% and remained stable, the effluent P concentration was below 0.5 mg·L-1, and the average P removal rate was 93.72%. At the same time, zoned sludge discharge (70% top sludge and 30% bottom sludge) can be used to screen out microorganisms, maintain good nitrosation and phosphorus removal performance, limit the particle size distribution, and ensure the growth advantages of AOB and DPAOs. Increases in the anoxic duration improved the growth rate of anoxic heterotrophic bacteria, causing them to secrete more EPS and ensuring granular sludge improvements and continued stability.Actual domestic sewage has a complex composition and relatively low carbon and nitrogen content. Anaerobic plug-flow influent can enhance the utilization of COD by aerobic granular sludge by providing a locally high concentration of substrate. In this study, intermittent aeration was used to cultivate aerobic granular sludge in a sequencing batch reactor (SBR), and actual domestic sewage was used as the feed water to inoculate the sewage plant sludge. In the R1 experiment, rapid anaerobic feeding was adopted, while in R2, anaerobic plug-flow feeding was adopted, to explore the impact of different feeding modes on the aerobic granular sludge system of domestic sewage. Under rapid anaerobic feeding in R1, the particle structure appeared earlier, but particle breakage occurred after 71 days of operation; the particle structure generated in R2 was denser than that of R1, the particle surfaces were smoother, and the denitrifying phosphorous accumulating organisms (DPAO) had a more enriching effect. In the final R1 and R2 reactors, the proportion of DPAO to phosphorous accumulating organisms (PAO) was 14.17% and 22.07%, respectively. The results show that the anaerobic plug-flow feeding mode can enhance the use of influent COD by granular sludge, which is conducive to enriching DPAO, generating denser and more stable particles, realizing "one carbon dual purpose" operation, and removing more nitrogen and phosphorus.As an intermediate form of microbial denitrification, nitrite serves as a key substrate for anaerobic ammonium oxidation (ANAMMOX). This study investigated the partial dentification (PD) characteristics and the coupling feasibility of PD+ANAMMOX in the biofilm system, using a moving bed biofilm reactor which was operated for 120 days. After 40 days of operation with a C/N ratio of 3.0 and filling fraction of 20%, the nitrate-to-nitrite transformation ratio (NTR) reached (69.38±3.53)%, and enzymatic assays indicated that the activities of nitrate reductase (NAR) had increased from 0.03 to 0.45 μmol·(min·mg)-1 while the activities of nitrite reductase (NIR) had decreased from 0.18 to 0.02 μmol·(min·mg)-1. Illumina high-throughput sequencing analysis revealed that the proportion of genus of Thauera bacteria to total microorganism increased from 0.3% (d1) to 37.27% (d64). Finally, the effluent had a total nitrogen (TN) concentration of (6.41±1.50) mg·L-1, indicating a total nitrogen removal ratio of (88.16±2.71)% and confirming the feasibility of PD+ANAMMOX in the biofilm system.This study explored the effect of sludge retention time (SRT) on ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) under intermittent gradient aeration, as well as the effect of the short-range nitrification endogenous denitrification phosphorus removal system on the treatment of low C/N ratio domestic sewage. In this study, an SBR reactor was used to cultivate aerobic granular sludge, using actual domestic sewage as the influent substrate. As the SRT decreased from 50 d to 30 d, the specific ammonia oxidation rate increased from 3.16 mg·(g·h)-1to 4.38 mg·(g·h)-1, and the specific nitrite oxidation rate decreased from 3.4 mg·(g·h)-1to 1.8 mg·(g·h)-1. The activity of NOB decreased by about 44%, resulting in short-range nitrification within the system. With an SRT of 30 d, the maximum nitrite accumulation was 6.93 mg·L-1. EGFR inhibitors list Because the reduced SRT led to a slight decrease in sludge concentration within the system, an aeration reduction strategy was adopted after 40 d, according to the DO curve. When the final SRT was 30 d, the effluent COD concentration was 40.76 mg·L-1, the TN concentration was 12.4 mg·L-1, the TP concentration was 0.31 mg·L-1, and the simultaneous removal of C, N and P was realized. Thus, a stable short-range nitrification endogenous denitrification phosphorus removal system was finally obtained. At the same time, the EPS content of aerobic granular sludge was negatively correlated with SRT, the protein content increased from 66.7 mg·g-1 to 95.1 mg·g-1, and the polysaccharide content remained in the range of 12.1-17.2 mg·g-1, indicating that the decreased SRT had a great effect on the protein content. With an SRT of 30 d, the PN/PS value was maintained at approximately 6.2, and the structural stability of aerobic granular sludge can be maintained under such conditions.To explore the effects of dissolved oxygen (DO) on the treatment of low carbon/nitrogen municipal wastewater, this study examined the characteristics of the microbial community in a low carbon source environment. The treatment process was conducted with the aeration area having DO concentrations of 2-3, 1-2, and lower than 1 mg·L-1. The results demonstrated that reduced DO concentration in the aeration area increased the efficiency of the nitrogen removal process by 20.23% and 80.54%, for external and internal carbon sources, respectively. Similarly, the efficiency of internal carbon source utilization in the phosphorus removal process increased by 13.89%, thus enhancing the nutrient removal efficiency of the low carbon/nitrogen wastewater treatment system. High-throughput sequencing and RDA analysis showed that reduced oxygen concentration motivated an adjustment in microbial community structure, causing functional microorganisms (i.e., Dechloromonas) to become dominant. In addition, the upregulation of genes associated with energy production and conversion, signal transduction, substrate transport, and metabolism provided favourable nutritional conditions for the proliferation of functional microorganisms in low carbon source conditions. This study provides a theoretical basis for improving the growth of microorganisms involved in the nutrient removal process when treating low carbon/nitrogen municipal wastewater.In order to understand the characteristics and interactions of the microbial community during the anaerobic ferric ammonium oxidation (FEAMMOX) process, this study investigated the effects of various forms of chelated iron on nitrogen removal efficiency and microbial community structure. After 77 days of reactor operation, the removal efficiency of total nitrogen was 83.32% for the ferric humate group, 43.67% for the ferric citrate group, 55.07% for the ferric sodium ethylene diamine tetraacetate group, and 12.65% for the ferric ammonium triacetate group. After the experiment, the abundance of denitrifying bacteria Comamonadaceae in ferric humate group was 17.57%, the abundance of Clostridium in ferric citrate group was 47.70%; and the abundance of denitrifying bacteria Thermomonas in the ferric sodium ethylene diamine tetraacetate group was 20.11%. This indicates that ferric humate is a more effective electron acceptor for the FEAMMOX process. The result of function prediction shows that the iron, sulfur, and nitrogen cycles are all closely related, with iron and sulfur metabolism playing an important role in nitrogen removal. In the humate group, iron respiration and the nitrogen cycle are more strongly correlated than other groups. Co-occurrence network analysis showed that the keystone species in the FEAMMOX process is Tessaracoccus.Wastewater from antibiotic production usually contains a huge amount of antibiotic resistance genes (ARG). Therefore, it is essential to study the dissemination and control of antibiotic resistance during the treatment of antibiotic production wastewater. The mutual influence between microbial community evolution, wastewater characteristics, and ARG was investigated using high-throughput sequencing and a variety of statistical analysis methods. Results showed that the influent characteristics had only a marginal influence on the microbial community of each treatment section. Methanogenic bacteria and sulfate-reducing bacteria were the dominant microbes in the anaerobic and anoxic tank. Chemical oxygen demand (COD), NO2--N, and PO43--P exhibited an intimate relationship with the microbial community, whereas biomass, NH4+-N, and COD showed a strong correlation with ARG and mobile genetic elements (MGE). In the sludge, more genera (including pathogenic bacteria) were significantly correlated with ARG and MGE than that in the wastewater, indicating that bacteria in the sludge had a greater chance of acquiring pathogenicity and resistance. Therefore, more attnetion should be given to waste sludge from the treatment plants of antibiotic production wastewater. This research could provide further understanding of antibiotic resistance dissemination and control during wastewater treatment, especially for antibiotic production wastewater.The release of manufactured nanomaterials (MNMs) into the environment has raised concerns about combined toxicological risks, as MNMs could significantly alter the environmental behavior and fate of co-existing contaminants. Numerous studies have been published on the combined toxicity of MNMs and co-existing contaminants, but the potential mechanisms controlling the combined toxicity, especially the biological response mechanism, remain unclear. This study investigated the combined toxicity of nano-titanium dioxide (nTiO2), a typical MNM, and the heavy metal cadmium (Cd2+), using Scenedesmus obliquus as the test organism. The molecular mechanism was examined under different concentrations, using an equivalent dose (toxic ratio 1 ∶1) on S. obliquus. The results showed that the 72h-EC50 of nTiO2 and Cd2+ at the equivalent dose was significantly higher than that of single exposure, indicating an antagonistic effect. Further transcriptomics analysis revealed that the photosynthesis, chlorophyll metabolism, and starch and sucrose metabolism pathways involved in the energy metabolism of S.