IWA Publishing
 IWA Publishing Journals   Subscriptions   Authors   Users   Librarians   FAQs 

Water Science & Technology Vol 42 No 1-2 pp 167–172 © IWA Publishing 2000

Interdependent environmental factors controlling nitrification in waters

D Kaplan*, R Wilhelm** and A Abeliovich***

* Department of Environmental Hydrology and Microbiology, The Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990 Israel
** Institut für Biologie des Stoffaustauschs ICG-6, Forschungszentrum Jülich, 52425 Jülich, Germany
*** Department of Environmental Hydrology and Microbiology, The Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede Boqer Campus, 84990 Israel


ABSTRACT
In many areas of the world limited water resources have lead to increased use of recycled water for agricultural and industrial purposes. Prior to releasing reclaimed water to consumers, excessive concentrations of inorganic nitrogenous compounds (ammonium, nitrite and nitrate) must be removed, and the water has to meet sanitary standards. The dynamics and abundance of the different nitrogenous compounds depend on the nitrification process (microbial oxidation of ammonia and nitrite). This is a key process in the nitrogen cycle and the autotrophic nitrifying bacteria catalyzing it are found in soils, sediments, wastewater, freshwater and marine water. Nitrification is a two-step process: first ammonia oxidizers convert ammonia to nitrite and then nitrite oxidizers convert nitrite to nitrate. An efficient nitrification process requires linked balanced activity of the two bacterial groups. Environmental factors that control nitrification affect ammonia and nitrite oxidizers differentially and thus disrupt the linkage between the two steps of the process. The effects of various environmental factors on the two bacterial groups and on the overall nitrification process are discussed. Light was identified to be a major factor inhibiting nitrification in a wastewater reservoir in Israel. Especially, nitrite oxidation was hindered causing the accumulation of nitrite during late spring and summer.

Full article (PDF Format)


eProduct: Buy this article for £24.00 (IWA MEMBER PRICE: £18.00)
All prices include VAT. For customers where VAT should not be applied, the VAT amount will be removed upon payment