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The kinetics of denitrification in permeable sediments


, : The kinetics of denitrification in permeable sediments. Biogeochemistry 113(1-3): 563-572

Permeable sediments comprise the majority of shelf sediments, yet the rates of denitrification remain highly uncertain in these environments. Computational models are increasingly being used to understand the dynamics of denitrification in permeable sediments, which are complex environments to study experimentally. The realistic implementation of such models requires reliable experimentally derived data on the kinetics of denitrification. Here we undertook measurements of denitrification kinetics as a function of nitrate concentration in carefully controlled flow through reactor experiments on sediments taken from six shallow coastal sites in Port Phillip Bay, Victoria, Australia. The results showed that denitrification commenced rapidly (within 30 min) after the onset of anoxia and the kinetics could be well described by Michaelis Menten kinetics with half saturation constants (apparent Km) ranging between 1.5 and 19.8 ?M, and maximum denitrification rate (Vmax) were in the range of 0.9 7.5 nmol mL?1 h?1. The production of N2 through anaerobic ammonium oxidation (anammox) was generally found to be less than 10 % of denitrification. Vmax were in the same range as previously reported in cohesive sediments despite organic carbon contents one order of magnitude lower for the sediments studied here. The ratio of sediment O2 consumption to Vmax was in the range of 0.02 0.09, and was on average much lower than the theoretical ratio of 0.8. As a consequence, models implemented with the theoretical ratio of 0.8 are likely to overestimate denitrification by a factor of ~3. The most likely explanation for this is that the microbial community is not able to instantaneously shift or optimally use a particular electron acceptor in the highly dynamic redox environment experienced in permeable sediments. In contrast to previous studies, we did not observe any significant rates of oxic denitrification.

US$19.90

DOI: 10.1007/s10533-012-9789-x


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Agarwal, S.; Wendorff, J.H.; Greiner, A., 2010: Progress in the field of electrospinning for tissue engineering applications. Electrospinning is an extremely promising method for the preparation of tissue engineering (TE) scaffolds. This technique provides nonwovens resembling in their fibrillar structures those of the extracellular matrix (ECM), and offering large surfa...

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Pywell, Michelle., 2000: The use of environmental enrichment in pinnipeds. Animal Keepers' Forum. June; 276: 276-278

Kampman, K.; Loerch, S., 1987: Effects of dry corn gluten feed on cattle feedlot performance. Beef cattle research report: (87-1) 10-20

Ricardo-Guerrero, R.H.rnan-Burbano, O.M.guel-Viveros, Z., 1977: Effect of liming on the development of organic phosphorus based on phosphate fertilization and its relation to phosphorus absorption by the plant in a typic dystrandept soil. Agrochimica 21 (5) 389-397

Becker Keir; Sakai Hitoshi; Merrill Russell B.; Adamson Andrew C.; Alexandrovich Joanne; Alt Jeffrey C.; Anderson Roger N.; Bideau Daniel; Gable Robert; Herzig Peter M.; Houghton Simon; Ishizuka Hideo; Kawahata Hodaka; Kinoshita Hajimu; Lovell Michael A.; Malpas John; Masuda Harue; Morin Roger H.; Mottl Michael J.; Pariso Janet E.; Pezard Philippe; Phillips Joseph; Sparks Joel; Uhlig Stefan, 1988: Sites 677 and 678. Proceedings of the Ocean Drilling Program, Part A: Initial Reports 111: 253-346

Mcqueen M.J., 1986: Conversion to international system units the canadian experience. Journal of the American Medical Association 256(21): 3001-3002

Chan, J.K.; Kapp, D.S., 2017: Clear Cell Ovarian Cancer: Optimum Management and Prognosis Remain Hazy. Gynecologic Oncology 147(2): 237-239