Chai B.,Xi'an University of Science and Technology |
Huang T.,Xi'an University of Architecture and Technology |
Huang T.,Key Laboratory of Northwest Water Resource |
Zhao X.,Xi'an University of Science and Technology
Chemical Engineering Transactions | Year: 2016
Nitrogen circulation and transformation on water-sediment interface of Source Water Reservoir was studied through comparative experiment between sterilization incubation and non-sterilization incubation. The results showed that NH4 +-N concentration in non-sterilization group continually increased and NO3 - decreased by 97.7%. In the sterilization group, there was no obvious change except the increase caused by diffusion. The S2- produced by sulfate reducing bacteria (SRB) weakened the denitrification. The content of TN and organic matter in the non-sterilization sediment samples decreased 26.28% and 18.37% respectively. After incubation, the quantity of ammonifiers, denitrifying bacteria and SRB increased greatly in the sediment of nonsterilization group. Therefore it can be concluded that microbes accelerated nitrogen circulation and conversion on water-sediment interface. Anaerobic condition is an important factor for NH4 +-N release. SRB can inhibit denitrification, thus slow down the nitrogen removal rate of sediment. Copyright © 2016, AIDIC Servizi S.r.l.
Chai B.-B.,Xi'an University of Science and Technology |
Huang T.-L.,Xi'an University of Architecture and Technology |
Huang T.-L.,Key Laboratory of Northwest Water Resource |
Zhao X.-G.,Xi'an University of Science and Technology |
Li Y.-J.,Xi'an University of Science and Technology
Journal of Environmental Biology | Year: 2015
Microbial communities in three drinking water reservoirs, with different depth in Xi'an city, were quantified by phospholipids fatty acids analysis and multivariate statistical analysis was employed to interpret their response to different hydrostatic pressure and other physico-chemical properties of sediment and overlying water. Principle component analyses of sediment characteristics parameters showed that hydrostatic pressure was the most important effect factor to differentiate the overlying water quality from three drinking water reservoirs from each other. NH4+ ontent in overlying water was positive by related to hydrostatic pressure, while DO in water-sediment interface and sediment OC in sediment were negative by related with it. Three drinking water reservoir sediments were characterized by microbial communities dominated by common and facultative anaerobic Gram-positive bacteria, as well as, by sulfur oxidizing bacteria. Hydrostatic pressure and physico-chemical properties of sediments (such as sediment OC, sediment TN and sediment TP) were important effect factors to microbial community structure, especially hydrostatic pressure. It is also suggested that high hydrostatic pressure and low dissolved oxygen concentration stimulated Gram-positive and sulfate-reducing bacteria (SRB) bacterial population in drinking water reservoir sediment. This research supplied a successful application of phospholipids fatty acids and multivariate analysis to investigate microbial community composition response to different environmental factors. Thus, few physico-chemical factors can be used to estimate composition microbial of community as reflected by phospholipids fatty acids, which is difficult to detect. © Triveni Enterprises, Lucknow (India).