Nitrous oxide (N(2)O) is a greenhouse gas with a global warming potential far exceeding that of CO(2). Soil N(2)O emissions are a product of two microbially mediated processes: nitrification and denitrification. Understanding the effects of landscape on microbial communities, and the subsequent influences of microbial abundance and composition on the processes of nitrification and denitrificati...

In unsaline loam soil, a laboratory experiment was undertaken studying the effect of using diluted saline water from Karoon lake at Fayoum Governorate, on transformations and subsequent nitrification of two ammoniacal fertilizers, namely (NH4)2SO4 and urea, in the presence or absence of natural organic amendments, namely clover and wheat straw. Ammonification and nitrification of both fertilize...

Nitrification, the chemoautotrophic process by which NH4-N is converted to NO,-N, is an integral biogeochemical transformation in stream ecosystems. Previous research has shown that experimental addition of dissolved organic C inhibits rates of nitrification, and that NH4-N addition stimulates rates of nitrification. In many streams, large amounts of C and N may be present in particulate and so...

The aim of this work was to study the effect of the herbicides glyphosate, nonanoic acid, and dichlorprop-P and the insecticides potassium oil, malation and Pyretrin and their combinations on nitrification. Nitrification was measured in slurries from the eutrophic and shallow Brabrand Lake (Aarhus, Denmark), by inhibiting oxidation of nitrite to nitrate with chloride. All herbicides and insecti...

The source of N(2)O produced in soil is often uncertain because denitrification and nitrification can occur simultaneously in the same soil aggregate. A technique which exploits the differential sensitivity of these processes to C(2)H(2) inhibition is proposed for distinguishing among gaseous N losses from soils. Denitrification N(2)O was estimated from 24-h laboratory incubations in which nitr...

Acclimation of nitrifying bacteria using inorganic carbon source (bicarbonate) and organic carbon source (bicarbonate + glucose) was performed in this study. Sequential batch reactors were inoculated by activated sludge (mixed culture of heterotrophic and nitrifying bacteria), and fed by synthetic wastewater contain high concentration of ammonium (1000 mg·L). Adapted nitrifying bacteria, only u...

Nitrification potential is the maximum capacity of a soil’s population of nitrifying bacteria to transform NH4+-N to NO3−-N. Time of season and the effect of several management practices on nitrification potentials were measured via an amended slurry method, shaken for 24 h at 25 ◦C. Management strategies that reduce potential nitrification rates without limiting plant N uptake may increase the...

conclusions based on nitrification and denitrification data, the best condition for nitrifying/ denitrifying performance was obtained by modified-ifas. hence, the modification can be used to obtain the best activities of microbial and nitrogen removal improvement. results employing the bet, surface area (sa), total pore volume (vp), and average size of the nanostructure were 0.4026 m2/g, 3.8089...

Nitrification, the microbial oxidation of ammonium to nitrate, is a central part of the nitrogen cycle. In the ocean's surface layer, the process alters the distribution of inorganic nitrogen species available to phytoplankton and produces nitrous oxide. A widely held idea among oceanographers is that nitrification is inhibited by light in the ocean. However, recent evidence that the primary or...

Nitrogen source and application time recommendations for rice are currently limited to applying an NH4-forming N source to a dry soil surface at the 5-lf growth stage for producers utilizing the delayed-flood production system. Fertilization trials were conducted at the Rice Research and Extension Center (RREC) and the Pine Tree Branch Station (PTBS) to investigate the use of urea amended with ...