title: Nitrogen reduction using bioreactive thin-layer capping (BTC) with biozeolite: A field experiment in a eutrophic river.
abstract: Bioreactive thin-layer capping (BTC) with biozeolite provides a potential remediation design that can sustainably treat N contamination from sediment and overlying water in eutrophic water bodies. Nitrogen (N) reduction using BTC with biozeolite was examined in a field incubation experiment in a eutrophic river in Yangzhou, Jiangsu Province, China. The biozeolite was zeolite with attached bacteria, including two isolated heterotrophic nitrifiers (Bacillus spp.) and two isolated aerobic denitrifiers (Acinetobacter spp.). The results showed that the total nitrogen (TN) reduction efficiency of the overlying water by BTC with biozeolite (with thickness of about 2mm) reached a maximum (56.69%) at day 34, and simultaneous heterotrophic nitrification and aerobic denitrification occurred in the BTC system until day 34. There was a significant difference in the TN concentrations of the overlying water between biozeolite capping and control (t-test; p<0.05). The biozeolite had very strong in situ bioregeneration ability. Carbon was the main source of nitrifier growth. However, both dissolved oxygen (DO) and carbon concentrations affected denitrifier growth. In particular, DO concentrations greater than 3mg/L inhibited denitrifier growth. Therefore, BTC with biozeolite was found to be a feasible technique to reduce N in a eutrophic river. However, it is necessary to further strengthen the adaptability of aerobic denitrifiers through changing domestication methods or conditions.
authors.affiliation: College of Civil Engineering, Huaqiao University, Xiamen 361021, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture & Technology, Xi'an 710055, China. Electronic address: zhenming@hqu.edu.cn.
authors.forename: Zhenming
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: School of Environmental and Municipal Engineering, Xi'an University of Architecture & Technology, Xi'an 710055, China. Electronic address: huangtinglin@xauat.edu.cn.
authors.forename: Tinglin
authors.initials: T
authors.lastname: Huang
authors.affiliation: College of Civil Engineering, Huaqiao University, Xiamen 361021, China.
authors.forename: Baoling
authors.initials: B
authors.lastname: Yuan
mesh_terms: D001419:Bacteria; D002244:Carbon; D002681:China; D058440:Denitrification; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005068:Eutrophication; D052836:Heterotrophic Processes; D058465:Nitrification; D009584:Nitrogen / Q000032:analysis / Q000737:chemistry*; D045483:Rivers / Q000737:chemistry* / Q000382:microbiology; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*; D017641:Zeolites / Q000737:chemistry*
chemical_list: D014874:Water Pollutants, Chemical; D017641:Zeolites; D002244:Carbon; D009584:Nitrogen
keywords: Bioreactive thin-layer capping (BTC); Biozeolite; Eutrophic river; Simultaneous nitrification and denitrification (SND)