Microbial biomass and species in the rhizosphere soil of Mirabilis jalapa（Linn.）（the saline-alkali soil contaminated by total petroleum hydrocarbon（TPH））were studied with the technology of phospholipid fatty ac...Microbial biomass and species in the rhizosphere soil of Mirabilis jalapa（Linn.）（the saline-alkali soil contaminated by total petroleum hydrocarbon（TPH））were studied with the technology of phospholipid fatty acids（PLFAs） analysis,to explore the effects of Mirabilis jalapa（Linn.） growth on the structure characteristics of microbial communities and degradation of TPH in the petroleum-contaminated salinealkali soil.The result showed that compared with the CK soil without Mirabilis jalapa（Linn.）,the kind change rates of PLFAs were 71.4%,69.2% and 33.3% in spring,summer and autumn,respectively,and the degradation of TPH increased by 47.6%,28.3%,and 18.9% in the rhizosphere soil in spring,summer and autumn,respectively.Correlation analysis was used to determine the correlation between the degradation of TPH and the soil microbial communities：77.8% of the microbial PLFAs showed positive correlation（the correlation coefficient r﹥0） with the degradation of TPH,and 55.6% of the PLFAs had high positive correlation with the degradation of TPH with a correlation coefficient r ≥0.8.In addition,the relative contents of SAT and MONO had high correlation with the degradation of TPH in the CK soil,and the correlation coefficients were 0.92 and 0.60,respectively;but in the rhizosphere soil,42.1% of the PLFAs had positive correlation with it,and only21.1% had high positive correlation with the degradation of TPH,the relative contents of TBSAT,MONO and CYCLO had moderate or low positive correlation with the degradation of TPH,and the correlation coefficients were 0.56,0.50 and 0.07 respectively.It was shown that the growth of mirabilis jalapa（Linn.） highly affected the microbial community structure and TPH degradation speed in the rhizosphere soil,providing a theoretical basis for the research on phytoremediation of petroleumcontaminated saline-alkali soil.展开更多
Cobalt and copper recovery from aqueous Co （II） and Cu（II） is one critical step for cobalt and copper wastewaters treatment. Previous tests have primarily examined Cu（II） and Co（II） removal in microbial electr...Cobalt and copper recovery from aqueous Co （II） and Cu（II） is one critical step for cobalt and copper wastewaters treatment. Previous tests have primarily examined Cu（II） and Co（II） removal in microbial electro- lysis cells （MECs） with abiotic cathodes and driven by microbial fuel cell （MFCs）. However, Cu（II） and Co（II） removal rates were still slow. Here we report MECs with biocathodes and driven by MFCs where enhanced removal rates of 6.0＋0.2mg·L^-1·h^-1 for Cu（II） at an initial concentration of 50 mg·L^-1 and 5.3~0.4mg·L^-1·h^-1 for Co（II） at an initial 40 mg· L^-1 were achieved, 1.7 times and 3.3 times as high as those in MECs with abiotic cathodes and driven by MFCs. Species of Cu（II） was reduced to pure copper on the cathodes of MFCs whereas Co（II） was removed associated with microorganisms on the cathodes of the connected MECs. Higher Cu（II） concentrations and smaller working volumes in the cathode chambers of MFCs further improved removal rates of Cu（II） （115.7 mg·L^-1·h^-1） and Co（II） （6.4 mg·L^-1·h^-1） with concomi- tantly achieving hydrogen generation （0.054-0.00 mol·mol^-1 COD）. Phylogenetic analysis on the bio- cathodes indicates Proteobacteria dominantly accounted for 67.9% of the total reads, followed by Firmicutes （14.0%）, Bacteroidetes （6.1%）, Tenericutes （2.5%）, Lentisphaerae （1.4%）, and Synergistetes （1.0%）. This study provides a beneficial attempt to achieve simultaneous enhanced Cu（II） and Co（II） removal, and efficient Cu（II） and Co（II） wastewaters treatment without any external energy consumption.展开更多
文摘Microbial biomass and species in the rhizosphere soil of Mirabilis jalapa（Linn.）（the saline-alkali soil contaminated by total petroleum hydrocarbon（TPH））were studied with the technology of phospholipid fatty acids（PLFAs） analysis,to explore the effects of Mirabilis jalapa（Linn.） growth on the structure characteristics of microbial communities and degradation of TPH in the petroleum-contaminated salinealkali soil.The result showed that compared with the CK soil without Mirabilis jalapa（Linn.）,the kind change rates of PLFAs were 71.4%,69.2% and 33.3% in spring,summer and autumn,respectively,and the degradation of TPH increased by 47.6%,28.3%,and 18.9% in the rhizosphere soil in spring,summer and autumn,respectively.Correlation analysis was used to determine the correlation between the degradation of TPH and the soil microbial communities：77.8% of the microbial PLFAs showed positive correlation（the correlation coefficient r﹥0） with the degradation of TPH,and 55.6% of the PLFAs had high positive correlation with the degradation of TPH with a correlation coefficient r ≥0.8.In addition,the relative contents of SAT and MONO had high correlation with the degradation of TPH in the CK soil,and the correlation coefficients were 0.92 and 0.60,respectively;but in the rhizosphere soil,42.1% of the PLFAs had positive correlation with it,and only21.1% had high positive correlation with the degradation of TPH,the relative contents of TBSAT,MONO and CYCLO had moderate or low positive correlation with the degradation of TPH,and the correlation coefficients were 0.56,0.50 and 0.07 respectively.It was shown that the growth of mirabilis jalapa（Linn.） highly affected the microbial community structure and TPH degradation speed in the rhizosphere soil,providing a theoretical basis for the research on phytoremediation of petroleumcontaminated saline-alkali soil.
文摘Cobalt and copper recovery from aqueous Co （II） and Cu（II） is one critical step for cobalt and copper wastewaters treatment. Previous tests have primarily examined Cu（II） and Co（II） removal in microbial electro- lysis cells （MECs） with abiotic cathodes and driven by microbial fuel cell （MFCs）. However, Cu（II） and Co（II） removal rates were still slow. Here we report MECs with biocathodes and driven by MFCs where enhanced removal rates of 6.0＋0.2mg·L^-1·h^-1 for Cu（II） at an initial concentration of 50 mg·L^-1 and 5.3~0.4mg·L^-1·h^-1 for Co（II） at an initial 40 mg· L^-1 were achieved, 1.7 times and 3.3 times as high as those in MECs with abiotic cathodes and driven by MFCs. Species of Cu（II） was reduced to pure copper on the cathodes of MFCs whereas Co（II） was removed associated with microorganisms on the cathodes of the connected MECs. Higher Cu（II） concentrations and smaller working volumes in the cathode chambers of MFCs further improved removal rates of Cu（II） （115.7 mg·L^-1·h^-1） and Co（II） （6.4 mg·L^-1·h^-1） with concomi- tantly achieving hydrogen generation （0.054-0.00 mol·mol^-1 COD）. Phylogenetic analysis on the bio- cathodes indicates Proteobacteria dominantly accounted for 67.9% of the total reads, followed by Firmicutes （14.0%）, Bacteroidetes （6.1%）, Tenericutes （2.5%）, Lentisphaerae （1.4%）, and Synergistetes （1.0%）. This study provides a beneficial attempt to achieve simultaneous enhanced Cu（II） and Co（II） removal, and efficient Cu（II） and Co（II） wastewaters treatment without any external energy consumption.
