Individual and combined assessment of risks of adverse effects to aquatic ecosystems of three chlorophenols(CPs),including 2,4dichlorophenol(2,4-DCP),2,4,6-trichlorophenol(2,4,6-TCP) and pentachlorophenol(PCP)...Individual and combined assessment of risks of adverse effects to aquatic ecosystems of three chlorophenols(CPs),including 2,4dichlorophenol(2,4-DCP),2,4,6-trichlorophenol(2,4,6-TCP) and pentachlorophenol(PCP),were conducted.A probabilistic approach based on the concentrations of CPs in surface waters of China was used to determine the likelihood of adverse effects.The potential risk of CPs in surface waters of China was determined to be of concern,especially PCP and mixtures of CPs.The risks of adverse effects were examined as the joint probabilities of exposure and response.The joint probability for PCP was 0.271 in the worst case and 0.111 in the median case,respectively.Based on the cumulative probability,5% of aquatic organisms included in the assessment would be affected 21.36% of the time in the worst case and 5.99% of the time in median case,respectively.For the mixtures of CPs,the joint probability were 0.171 in the worst case and 0.503 in median case,respectively and 5% of species would be affected 49.83% of the time for the worst case and 12.72% in the median case,respectively.Risks of effects of the individual CPs,2,4-DCP and 2,4,6-TCP were deemed to be acceptable with a overlapping probability of 0.1 with 5% of species being affected less than 4% of the time.展开更多
The effect of salinity on sludge alkaline fermentation at low temperature(20°C) was investigated, and a kinetic analysis was performed. Different doses of sodium chloride(Na Cl, 0–25 g/L) were added into the...The effect of salinity on sludge alkaline fermentation at low temperature(20°C) was investigated, and a kinetic analysis was performed. Different doses of sodium chloride(Na Cl, 0–25 g/L) were added into the fermentation system. The batch-mode results showed that the soluble chemical oxygen demand(SCOD) increased with salinity. The hydrolysate(soluble protein, polysaccharide) and the acidification products(short chain fatty acids(SCFAs), NH+4–N, and PO_4^(3-)–P) increased with salinity initially, but slightly declined respectively at higher level salinity(20 g/L or 20–25 g/L). However, the hydrolytic acidification performance increased in the presence of salt compared to that without salt.Furthermore, the results of Haldane inhibition kinetics analysis showed that the salt enhanced the hydrolysis rate of particulate organic matter from sludge particulate and the specific utilization of hydrolysate, and decreased the specific utilization of SCFAs. Pearson correlation coefficient analysis indicated that the importance of polysaccharide on the accumulation of SCFAs was reduced with salt addition, but the importance of protein and NH+4–N on SCFA accumulation was increased.展开更多
For comprehensive insights into the influences of sulfate on performance,microbial community and metabolic pathways in the acidification phase of a two-phase anaerobic system,a laboratory-scale acidogenic bioreactor w...For comprehensive insights into the influences of sulfate on performance,microbial community and metabolic pathways in the acidification phase of a two-phase anaerobic system,a laboratory-scale acidogenic bioreactor was continuously operated to treat wastewater with elevated sulfate concentrations from 2000 to 14000 mg/L.The results showed that the acidogenic bioreactor could achieve sulfate reduction efficiency of greater than 70%for influent sulfate content less than 12000 mg/L.Increased sulfate induced the accumulation of volatile fatty acids(VPAs),especially propionate and butyrate,which was the primary negative effects to system performance under the high-sulfate environment.High-throughput sequencing coupled with PICRUSt2 uncovered that the accumulation of VFAs was triggered by the decreasing of genes encoding short-chain acyl-CoA dehydrogenase(EC:1.3.8.1),regulating the transformation of propanoyl-CoA to propenoyl-CoA and butanoyl-CoA to crotonyl-CoA of propionate and butyrate oxidation pathways,which made these two process hardly proceed.Besides,genes encoding(EC:1.3.8.1)were mainly carried by order Clostridiales.Desulfovibrio was the most abundant sulfate-reducing bacteria and identified as the primary host of dissimilatory sulfate reduction ftinctional genes.Functional analysis indicated the dissimilatory sulfate reduction process predominated under a low sulfate environment,but was not favored under the circumstance of high-sulfate.With the increase of sulfate,the assimilatory sulfate reduction process finally overwhelmed dissimilatory as the dominant sulfate reduction pathway in acidogenic bioreactor.展开更多
The authors regret that the printed version of the above article contained an error of the afliation of one of the co-authors Baikun Li.The correct and final version is shown below:Baikun Li,Department of Civil and En...The authors regret that the printed version of the above article contained an error of the afliation of one of the co-authors Baikun Li.The correct and final version is shown below:Baikun Li,Department of Civil and Environmental Engineering,University of Connecticut,Storrs,CT 06269,USA The authors would like to apologise for any inconvenience caused.展开更多
基金supported by the National Natural Science Foundation of China(No.20737001,20977047)the Major State Basic Research Development Program (No.2008CB418102)+3 种基金the Specialized Research Fund for the Doctoral Program of Higher Education(No. 200802841030)the National Major Project of Science & Technology Ministry of China(No.2008ZX08526-003)supported by the Canada Research Chair Program,and is at-large Chair Professor at the Department of Biology and Chemistry and State Key Laboratory in Marine Pollution,City University of Hong Kongthe Einstein Professor Program of the Chinese Academy of Sciences and the Visiting Professor Program of King Saud University
文摘Individual and combined assessment of risks of adverse effects to aquatic ecosystems of three chlorophenols(CPs),including 2,4dichlorophenol(2,4-DCP),2,4,6-trichlorophenol(2,4,6-TCP) and pentachlorophenol(PCP),were conducted.A probabilistic approach based on the concentrations of CPs in surface waters of China was used to determine the likelihood of adverse effects.The potential risk of CPs in surface waters of China was determined to be of concern,especially PCP and mixtures of CPs.The risks of adverse effects were examined as the joint probabilities of exposure and response.The joint probability for PCP was 0.271 in the worst case and 0.111 in the median case,respectively.Based on the cumulative probability,5% of aquatic organisms included in the assessment would be affected 21.36% of the time in the worst case and 5.99% of the time in median case,respectively.For the mixtures of CPs,the joint probability were 0.171 in the worst case and 0.503 in median case,respectively and 5% of species would be affected 49.83% of the time for the worst case and 12.72% in the median case,respectively.Risks of effects of the individual CPs,2,4-DCP and 2,4,6-TCP were deemed to be acceptable with a overlapping probability of 0.1 with 5% of species being affected less than 4% of the time.
基金supported by the National Natural Science Foundation of China (No. 51178007)
文摘The effect of salinity on sludge alkaline fermentation at low temperature(20°C) was investigated, and a kinetic analysis was performed. Different doses of sodium chloride(Na Cl, 0–25 g/L) were added into the fermentation system. The batch-mode results showed that the soluble chemical oxygen demand(SCOD) increased with salinity. The hydrolysate(soluble protein, polysaccharide) and the acidification products(short chain fatty acids(SCFAs), NH+4–N, and PO_4^(3-)–P) increased with salinity initially, but slightly declined respectively at higher level salinity(20 g/L or 20–25 g/L). However, the hydrolytic acidification performance increased in the presence of salt compared to that without salt.Furthermore, the results of Haldane inhibition kinetics analysis showed that the salt enhanced the hydrolysis rate of particulate organic matter from sludge particulate and the specific utilization of hydrolysate, and decreased the specific utilization of SCFAs. Pearson correlation coefficient analysis indicated that the importance of polysaccharide on the accumulation of SCFAs was reduced with salt addition, but the importance of protein and NH+4–N on SCFA accumulation was increased.
基金We gratefully acknowledge generous support provided by the National Natural Science Foundation of China(No.51978328).
文摘For comprehensive insights into the influences of sulfate on performance,microbial community and metabolic pathways in the acidification phase of a two-phase anaerobic system,a laboratory-scale acidogenic bioreactor was continuously operated to treat wastewater with elevated sulfate concentrations from 2000 to 14000 mg/L.The results showed that the acidogenic bioreactor could achieve sulfate reduction efficiency of greater than 70%for influent sulfate content less than 12000 mg/L.Increased sulfate induced the accumulation of volatile fatty acids(VPAs),especially propionate and butyrate,which was the primary negative effects to system performance under the high-sulfate environment.High-throughput sequencing coupled with PICRUSt2 uncovered that the accumulation of VFAs was triggered by the decreasing of genes encoding short-chain acyl-CoA dehydrogenase(EC:1.3.8.1),regulating the transformation of propanoyl-CoA to propenoyl-CoA and butanoyl-CoA to crotonyl-CoA of propionate and butyrate oxidation pathways,which made these two process hardly proceed.Besides,genes encoding(EC:1.3.8.1)were mainly carried by order Clostridiales.Desulfovibrio was the most abundant sulfate-reducing bacteria and identified as the primary host of dissimilatory sulfate reduction ftinctional genes.Functional analysis indicated the dissimilatory sulfate reduction process predominated under a low sulfate environment,but was not favored under the circumstance of high-sulfate.With the increase of sulfate,the assimilatory sulfate reduction process finally overwhelmed dissimilatory as the dominant sulfate reduction pathway in acidogenic bioreactor.
文摘The authors regret that the printed version of the above article contained an error of the afliation of one of the co-authors Baikun Li.The correct and final version is shown below:Baikun Li,Department of Civil and Environmental Engineering,University of Connecticut,Storrs,CT 06269,USA The authors would like to apologise for any inconvenience caused.