The regulatory effects of environmental factors on denitrification were studied in the sediments of Meiliang Bay, Taihu Lake, in a monthly sampling campaign over a one-year period. Denitrification rates were measured in slurries of field samples and enrichment experiments using the acetylene inhibition technique. Sediment denitrification rates in inner bay and outer bay ranged from 2.8 to 51.5 nmol N2/(g dw (dry weight) x hr) and from 1.5 to 81.1 nmol N2/(g dw x hr), respectively. Sediment denitrification rates were greatest in the spring and lowest in the summer and early autumn, due primarily to seasonal differences in nitrate concentration and water temperature. For each site, positive and linear relationships were regularly observed between denitrification rate and water column nitrate concentration. Of various environmental factors on denitrification that we assessed, nitrate was determined to be the key factor limiting denitrification rates in the sediments of Meiliang Bay. In addition, at the two sites denitrification rates were also regulated by temperature. The addition of organic substrates had no significant effect on denitrification rate, indicating that sediment denitrification was not limited by organic carbon availability in the sediments. Nitrate in the water column was depleted during summer and early autumn, and this suppressed effective removal of nitrogen from Taihu Lake by denitrification.
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http://dx.doi.org/10.1016/s1001-0742(09)60205-9 | DOI Listing |
Water Res
January 2025
Guangdong Basic Research Center of Excellence for Ecological Security and Green Development, Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds, Institute of Environmental and Ecological Engineering, Guangdong University of Technology, Guangzhou, 510006, China.
Riverine NO and N fluxes, key components of the global nitrogen budget, are known to be influenced by river size (often represented by average river width), yet the specific mechanisms behind these effects remain unclear. This study examined how environmental and microbial factors influenced sediment NO and N fluxes across rivers with varying widths (2.8 to 2,000 m) in China.
View Article and Find Full Text PDFEnviron Sci Process Impacts
January 2025
Department of Civil and Environmental Engineering, University of Pittsburgh, Pittsburgh, PA, USA.
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View Article and Find Full Text PDFEnviron Sci Technol
January 2025
School of Engineering, Hangzhou Normal University, Hangzhou 310018, China.
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View Article and Find Full Text PDFSci Total Environ
January 2025
Department of Water Resources and Ecosystems, IHE Delft Institute for Water Education, P.O. Box 3015, 2601 DA Delft, the Netherlands; Department of Ecoscience, Freshwater Ecology, University of Aarhus, Aarhus, Denmark. Electronic address:
Sci Total Environ
January 2025
Facultad de Ingeniería y Ciencias, Universidad Adolfo Ibáñez, Avda. Padre Hurtado 750, Viña del Mar, Chile.
Nitrogen contamination of water sources poses significant environmental and health risks. The sulfur-driven simultaneous nitrification and autotrophic denitrification (SNAD) process offers a cost-effective solution, as it operates in a single reactor, requires no organic carbon addition, and produces minimal sludge. However, this process remains underexplored, with microbial population dynamics, their interactions, and their implications for process efficiency not yet fully understood.
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