The effects of single Cd^(2+)and Pb^(2+),and combined Cd^(2+)and Pb^(2+)on dehydrogenase activity and polysaccharide content of the substrate biofilms in the integrated vertical-flow constructed wetland(IVCW)were stud...The effects of single Cd^(2+)and Pb^(2+),and combined Cd^(2+)and Pb^(2+)on dehydrogenase activity and polysaccharide content of the substrate biofilms in the integrated vertical-flow constructed wetland(IVCW)were studied.Dehydrogenase activities decreased linearly with the increasing concentrations of Cd^(2+)and Pb^(2+)at different times(6,24,72,and 120 h).The activities at both 6 and 24 h were significantly higher than that at 72 and 120 h in the case of single and combined treatments.The single Cd^(2+)and...展开更多
The spacial distribution characteristics, activity and degradation capability of the biofilm in integrated vertical-flow constructed wetland were investigated. Results showed that the biofilm widely distributed in the...The spacial distribution characteristics, activity and degradation capability of the biofilm in integrated vertical-flow constructed wetland were investigated. Results showed that the biofilm widely distributed in the substrate of integrated vertical-flow constructed wetland and mainly in the 0-10 cm top layer where the activity ofdehydrogenase of the biofilm was also higher than that of other layers. The water quality could also affect the activity of the biofilm, for the TF（1,3,5-Triphenylformazan） amount reduced by the biofim incubated in water of the higher eutrophication was larger, too. The PCP （pentachlorophenol） removal rate by the substrate with biofilm was 1.5 times that without biofilm. In total, the biofilm of the down-flow chamber appeared larger biomass, higher dehydrogenase activity and stronger degradation capability of organic contamination than that in up-flow chamber and it was the major place for removal of the organic matters in waste water.展开更多
The integrated vertical-flow constructed wetland（IVCW） was simulated with three suits of designed experiment columns planted with Kandelia candel.Units A,B and C were irrigated with sewage of different salinity（A...The integrated vertical-flow constructed wetland（IVCW） was simulated with three suits of designed experiment columns planted with Kandelia candel.Units A,B and C were irrigated with sewage of different salinity（A：10‰ B：20‰,C：30‰）,respectively.The removal rates of dissolved organic carbon（DOC）,NH3-N and NO3--N dropped 90.4%-48.6%,80.2%-40.3% and 84.8%-60.9%,respectively,when salinity increases from 10‰ to 30‰.The removal rate of TP increased 14%-31.2%,oppositely.A 20-day inflow salinity drastic change shock affective trial was done on units D and E.Unit D was used as a control and irrigated with saline sewage（20‰）.Unit E was irrigated with sewage with low salinity（5‰） as a salinity drastic change shock on the third and fourth days.DOC,NH3-N and NO3--N removal efficiency of unit E showed a three-stage process of change,＂rapidly decrease,increase beyond the normal standard,and then back to the normal standard＂.TP removal value was negative during the 2-day shock period.展开更多
文摘The effects of single Cd^(2+)and Pb^(2+),and combined Cd^(2+)and Pb^(2+)on dehydrogenase activity and polysaccharide content of the substrate biofilms in the integrated vertical-flow constructed wetland(IVCW)were studied.Dehydrogenase activities decreased linearly with the increasing concentrations of Cd^(2+)and Pb^(2+)at different times(6,24,72,and 120 h).The activities at both 6 and 24 h were significantly higher than that at 72 and 120 h in the case of single and combined treatments.The single Cd^(2+)and...
文摘The spacial distribution characteristics, activity and degradation capability of the biofilm in integrated vertical-flow constructed wetland were investigated. Results showed that the biofilm widely distributed in the substrate of integrated vertical-flow constructed wetland and mainly in the 0-10 cm top layer where the activity ofdehydrogenase of the biofilm was also higher than that of other layers. The water quality could also affect the activity of the biofilm, for the TF（1,3,5-Triphenylformazan） amount reduced by the biofim incubated in water of the higher eutrophication was larger, too. The PCP （pentachlorophenol） removal rate by the substrate with biofilm was 1.5 times that without biofilm. In total, the biofilm of the down-flow chamber appeared larger biomass, higher dehydrogenase activity and stronger degradation capability of organic contamination than that in up-flow chamber and it was the major place for removal of the organic matters in waste water.
基金Supported by the National High Technology Research and Development Program of China (863 Program) (2009ZX07106-002-004)the National Natural Science Foundation of China (50808172,30870221)
文摘The integrated vertical-flow constructed wetland（IVCW） was simulated with three suits of designed experiment columns planted with Kandelia candel.Units A,B and C were irrigated with sewage of different salinity（A：10‰ B：20‰,C：30‰）,respectively.The removal rates of dissolved organic carbon（DOC）,NH3-N and NO3--N dropped 90.4%-48.6%,80.2%-40.3% and 84.8%-60.9%,respectively,when salinity increases from 10‰ to 30‰.The removal rate of TP increased 14%-31.2%,oppositely.A 20-day inflow salinity drastic change shock affective trial was done on units D and E.Unit D was used as a control and irrigated with saline sewage（20‰）.Unit E was irrigated with sewage with low salinity（5‰） as a salinity drastic change shock on the third and fourth days.DOC,NH3-N and NO3--N removal efficiency of unit E showed a three-stage process of change,＂rapidly decrease,increase beyond the normal standard,and then back to the normal standard＂.TP removal value was negative during the 2-day shock period.
