N2O emission in the anaerobic ammonium oxidation (anammox) process is of growing concern. In this study, effects of substrate concentrations on N2O emissions were investigated in an anammox reactor. Extremely high N2O emissions of 1.67 % were led by high NH4-N concentrations. Results showed that N2O emissions have a positive correlation with NH4-N concentrations in the anammox reactor. Reducing...

Aims Land use management affects plant carbon (C) supply and soil environments and hence alters soil nitrogen (N) dynamics, with consequent feedbacks to terrestrial ecosystem productivity. The objective of this study was to better identify mechanisms by which land-use management (clipping and shading) regulates soil N in a tallgrass prairie, OK, USA. Methods We conducted 1-year clipping and sha...

The extent to which atmospheric nitrogen (N) deposition reflects land use differences and biogenic versus fossil fuel reactive N sources remains unclear yet represents a critical uncertainty in ecosystem N budgets. We compared N concentrations and isotopes in precipitation-event bulk (wet + dry) deposition across nearby valleys in northern Utah with contrasting land use (highly urban versus int...

The accumulation of proline impacts the defense mechanisms plants against harmful effects adverse environmental conditions; however, its concentration in is associated with metabolism N. Therefore, exogenous organic [glutamate (Glu)/arginine (Arg)] and inorganic [nitrate (NO3−)/ammonium (NH4+)] N on (Pro) rice under trivalent chromium [Cr(III)] stress were studied through using mass balance mat...

Elevated concentrations of reactive nitrogen (N) in precipitation have been reported for many cities in China. Due to increased use of fossil fuels and expansion in agriculture, further increases in deposition of ammonia (NHx) and reactive N oxides (NOy) are predicted. Increased deposition of reactive N is likely to affect N dynamics and N runoff in forest ecosystems. Yet, in China little work ...

Growth comparisons were made between a microalgal consortium and Scenedesmus sp. cultivated in treated wastewater (TWw) enriched with 1 mL·L–1 Bayfolan Forte fertilizer (BM), TWw (NH4)2HPO4 (PAM), NH4HCO3 (BCAM), tap water piggery (PEM), digestate (PDM), raw (Ww). Nitrogen (N) content the media, except for TWw, was adjusted to 80 mg·L–1 N (NH4+-N NO3–-N). Unconventional low-cost media lower nut...

Over a period of several days, rhythmic changes in extracellular NH4+ concentration take place in cultures of the cyanobacterium Microcystis firma (Breb et Lenorm.) Schmidle, strain Gromov/St. Petersb. 398, under conditions of restricted CO2 supply and light/dark alternation. The changes are enhanced by nitrate supply. Among the various processes generating intracellular NH4+ (NH4+ uptake, NO3r...

Recent evidence associates the persistence of invasive plant species with disturbance and fluctuations in distinct forms of mineral N in soils. We conducted soil and hydroponic experiments to investigate the influence of N form and availability on germination and seedling development of 2 invasive annual grasses, cheatgrass (Bromus tectorum) and medusahead (Taeniatherum caput-medusae) and 6 per...