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The logBCFs, BSSAFs, and BSAFs of PCDPS congeners in fishes were determined to be 3.91-5.18, 0.0500-2.33, and 0.0360-4.94 L/kg, respectively. The organic carbon normalized partition coefficients (logKoc) of PCDPSs in surface water-SPM (4.61-5.54 L/g) and surface water-sediment (4.38-5.69 L/g) systems were determined, and it was found that highly chlorinated PCDPSs were more prone to migrate from water to sediment and SPM. The toxic equivalent (TEQ) values of PCDPSs in the samples (lower than 10-1 pg/g or pg/L) and daily intake via fish consumption (0.180-0.340 μg/kg/day) were estimated for humans, and cumulative risk quotients (RQs) after correction at ten sampling sites (0.065-0.66) were calculated for green algae. The findings elucidated the environmental behaviour of PCDPSs in Chaohu Lake.Granular activated carbon (GAC) filtration impacts pathogen colonization and bacterial communities in drinking water. However, the effects of ozone and heterogeneous Fenton oxidation on microbial community composition, in particular opportunistic pathogens (OPs), and their metabolic potential in biofilms and effluents from GAC filtration are not fully understood. The results of our pilot-scale test indicated that Fenton-GAC filtration removed more dissolved organic carbon (DOC, 1.25 mg/L) than ozone-GAC filtration (0.98 mg/L). Excitation-emission matrix (EEM) results showed that Fenton-GAC removed more tyrosine-like proteins and fulvic acid-like materials, while ozone-GAC removed more humic acid-like compounds and tryptophan-like proteins. Illumina HiSeq analysis indicated that Curvibacter and Hydrogenophaga dominated in the Fenton-GAC biofilm, while Bradyrhizobium, Aquabacterium and Limnobacter were predominant in the ozone-GAC biofilm. Functional prediction suggested that the microbial functional gene related to glyoxylate and dicarboxylate metabolism (the pathway for carbohydrate metabolism) was higher in the Fenton-GAC biofilm, resulting in higher contents of protein in extracellular polymeric substances (EPS) in the Fenton-GAC biofilm. Therefore, there were fewer bacteria that detached from the biofilm into the water during the Fenton-GAC filtration process. The lower EPS content in the effluents from Fenton-GAC resulted in bacteria, including OPs, being easier to remove by chlorine. However, ozone oxidation removed more bacteria, including different OPs, than Fenton oxidation, which contributed to fewer bacteria and OPs in the effluents from ozone-GAC. Overall, our results provide a Fenton-GAC treatment process to remove DOC and control OPs in drinking water systems, the cost of which was comparable to that of ozone-GAC.Response of aquatic organisms to eutrophication have been well reported, while less studies are available for the recovery of eutrophic lakes following a reduction in the external loading, especially for systems where nitrogen is reduced but the phosphorus concentration is maintained high due to internal loading. Diatoms are nitrate (NO3-N) opportunists but can also use ammonium (NH4-N). They may, therefore, be more sensitive to nitrogen reduction than other algae that typically prefer NH4-N. We document the variations of nutrients and diatoms in subtropical, eutrophic Lake Taihu over 28 yr during which a reduction of the external loading resulted from lake management. According to the results of change point analysis, data on environmental variables were divided into two periods (P1 1992-2006; P2 2007-2019) with two different seasons (WS Winter-Spring; SA Summer-Autumn), respectively. Compared with P1-WS, the concentration of NH4-N decreased significantly whereas NO3-N showed no significant change in P2-WS. Thus, parallel reductions in external nitrogen loading, along with variations in dominant inorganic nitrogen, will stimulate the growth of diatom and therefore increase the total biomass of phytoplankton in still high internal phosphorus loading, which is should be regarded as a good sign of restoration measures.Algal organic matter (AOM) is a potential precursor of disinfection byproducts (DBPs) in water treatment. It is a major challenge to identify macromolecular DBPs due to the diversity of AOM. In this study, Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR/MS) was applied to diagnose the AOM diversity after algae removal by plasma oxidation and to recognize the macromolecular DBPs in subsequent chlorination. Significant removal of AOM released by M. aeruginosa, C. raciborskii, and A. spiroies was achieved by plasma oxidation, accompanied by decrease in the proportion of CHNO formulas and increase in CHO formulas. [https://www.selleckchem.com/products/dooku1.html Mechanosensitive Cha antagonist] Without plasma treatment, chlorination generated approximately 2486 macromolecular carbonaceous DBPs (C-DBPs) and 1984 nitrogenous DBPs (N-DBPs), with C11HnOmClx and C18HnNmOzClx as the most abundant DBPs. The numbers of C-DBPs and N-DBPs decreased by 63.3% and 62.9%, respectively, if plasma treatment was applied prior to chlorination. Network computational analysis revealed that Cl substitution was the main formation pathway of AOM-derived DBP formation rather than HOCl addition. The precursors of macromolecular DBPs contained a characteristic atomic number of C and O (7 ≤ C ≤ 18; 3 ≤ O ≤ 11). This study firstly disclosed the relationship between AOM diversity and novel macromolecular DBPs during algae-laden water treatment.Tetracycline (TC) has been frequently detected in various environments, thus promoting the occurrence of resistance in bacterial populations. In this study, a suite of soybean straw biochars (SSBs) were fabricated under different pyrolysis temperatures (600-1000 °C), which were utilized as peroxydisulfate (PS) activators for TC degradation and TC resistant Escherichia coli (E. coli) disinfection. The purification effect of SSBs/PS systems manifested obvious positive dependence on pyrolysis temperature of SSBs with SSB1000/PS system obtained the superior TC degradation, E. coli disinfection and coexisting TC and E. coli elimination capacity. The leakage of intracellular DNA and the degradation of total DNA and extracellular DNA was revealed no matter in alone E. coli or combined pollution which can also be supported by the gradual ruptured bacterial morphology and attenuated internal components. It can be found that TC adsorption in SSBs played a significant role on TC degradation, while the electrostatic repulsion always existed between E. coli and SSB1000. Furthermore, a battery of solid evidences collectively demonstrated the significant different purification mechanism of TC and E. coli. The TC degradation was achieved dominantly by surface-bound radicals, while bactericidal activity should be attributed to free SO4·- in bulk solutions. In contrast to other SSBs, the largest mesopore volumes, highest C=O content, lowest interfacial charge transfer resistance and strongest electron donating capacity explained the outperformed catalytic performance of SSB1000.The Jiaozhou Bay as a model marine ecosystem in China has been intensively investigated over the last 90 years. However, detailed phytoplankton community composition, spatial-temporal dynamics, and its assembly mechanism were still unclear. To address these, we systematically examined the composition and spatial-temporal dynamics of phytoplankton in the Jiaozhou Bay through high-throughput sequencing of 18S rDNA V4. Analysis of 468 samples from 12 sampling sites over one full year revealed much higher phytoplankton diversity than previous reports, and strong seasonal succession patterns. Some phytoplankton also showed spatial variations, although the phytoplankton community didn't show significant distance-decay pattern. Environmental factors (especially temperature), species-species interrelationships and unique resting stages were uncovered to be the main contributors instead of stochastic process in shaping the phytoplankton community assembly. The overwhelming positive correlations between phytoplankton and other protists suggested that coevolution might be critical in this marine ecosystem. Complementary distributions of different amplicon sequence variants (ASVs) of same genera, such as Skeletonema marinoi (ASV_2) and Skeletonema tropicum (ASV_263) of the genus Skeletonema, suggested that phytoplankton have evolved differentially to exploit a wide range of ecological niches. This study laid a solid foundation for asertaining phytoplankton composition and spatial-temporal dynamics in temperate seawaters and mechanisms underlying phytoplankton community assembly, allowing in-depth studies of marine ecology.Removal of planktivorous fish is used extensively in northern temperate lakes to reduce phytoplankton abundance via enhanced zooplankton grazing. However, whether this method would work also in large subtropical highland lakes to alleviate cyanobacterial blooms is unknown. We conducted a one-year pilot in situ experiment where we removed a substantial biomass of fish in a fenced-in area, followed by a 3-year whole-lake experiment where the dominant fish species (Japanese smelt) was removed in Lake Erhai in southwest China. The fencing experiments showed that between July and November, when the biomass of the removed stock reached 4 g/m2, the zooplankton biomass inside the fence increased significantly compared to a control fence. In the full-lake experiment, we found that sustained removal of Japanese smelt led to an increase in the biomass of cladocerans (Daphnia spp. but especially of Bosmina spp.) and a significant decrease in the biomass of Cyanobacteria and Chlorophyta. Additionally, a marked increase in the ratio of zooplankton to phytoplankton biomass, as well as an increase in the body size of cladocerans, emphasising the importance of enhanced top-down control for mitigating cyanobacterial blooms following extensive fish removal. Our results reveal that removal of small fish (here Japanese smelt) can lead to a reduction of the phytoplankton and cyanobacteria biomass through a trophic cascade in highland deep subtropical lakes. Thus fish removal may be a feasible additional restoration tool to external nutrient loading reduction in such lakes.Foaming is a key issue that threatens the efficient and stable operation of the anaerobic digestion process. This study introduced three disturbances to induce foaming and explored the responses of physicochemical parameters, microbial communities, and metabolites to reveal the foaming mechanism. Under the three disturbance conditions, extracellular polymeric substances (EPS)-related parameters are significantly positively correlated with foam height, and EPS may cause foam by lowering the surface tension. Microorganisms that are more tolerant to high acid or high ammonia stress environments were identified after foaming, and they could resist the stress environment by producing more EPS. The up-regulated expression of sphingomyelin or ceramide was discovered after foaming, involved in the signal molecular transduction process of cell apoptosis or necrosis, which might be related to EPS production. Pantothenic acid involved in pantothenate and CoA biosynthesis pathways was down-regulated expression after foaming, which might be related to the hindered degradation of EPS. The response of multi-scale parameters in the foaming process shows that EPS is the key factor in foaming events.