The dynamics of nitrogen in terrestrial environments may be fundamentally flawed due to the lack of consideration of the uptake of organic N by plants (Chapin et al., 1993 (Jones et al.2005)). Crops that possess the ability to compete for and absorb dissolved organic N (DON) may gain a significant competitive advantage compared to those relying on inorganic N forms produced by mineralization (C...

Isotope pool dilution studies are increasingly reported in the soils and ecology literature as a means of measuring gross rates of nitrogen (N) mineralization, nitrification, and inorganic N assimilation in soils. We assembled data on soil characteristics and gross rates from 100 studies conducted in forest, shrubland, grassland, and agricultural systems to answer the following questions: What ...

Benthic chambers were used to measure in situ fluxes of dissolved gases (N2, O2, and N2O) and inorganic nutrients (NO3 , NH4 , and PO4 3 ) in continental shelf sediments of the Mid-Atlantic Bight during spring through autumn (May– November). Denitrification was determined by the rate of increase in N2 relative to Ar, measured using membrane-inlet mass spectrometry. Although sediments were a sou...

In most terrestrial ecosystems, nitrogen (N) is the most limiting nutrient for plant growth. Honey bees may help alleviate this limitation because their feces (frass) have high concentration of organic nitrogen that may decompose in soil and provide inorganic N to plants. However, information on soil N processes associated with bee frass is not available. The objectives of this work were to 1) ...

J. M. H. Knops,* K. L. Bradley and D. A. Wedin School of Biological Sciences, School of Natural Resource Sciences, University of Nebraska, 348 Manter Hall, Lincoln, NE 68588, USA. *Correspondence: E-mail: [email protected] Abstract Plant species are hypothesized to impact ecosystem nitrogen cycling in two distinctly different ways. First, differences in nitrogen use efficiency can lead to positiv...

There has and continues to be concern about the effects of elevated nitrogen (N) deposition on natural ecosystems. In this paper, research on natural ecosystems, including wetlands, heathlands, grasslands, steppe, naturally regenerated forests and deserts, is evaluated to determine what is known about nitrogen cycling in these ecosystems, the effects of elevated nitrogen on them and to identify...

Pseudomonas sp. strain ADP uses the herbicide atrazine as the sole nitrogen source. We have devised a simple atrazine degradation assay to determine the effect of other nitrogen sources on the atrazine degradation pathway. The atrazine degradation rate was greatly decreased in cells grown on nitrogen sources that support rapid growth of Pseudomonas sp. strain ADP compared to cells cultivated on...

Several advanced oxidation processes such as hydrogen peroxide photolysis, the Fenton treatment, photo-Fenton treatment, and ozonation combined with hydrogen peroxide and UVradiation for the destruction of 2,4-dinitrophenol were studied. Advanced oxidation processes, especially the Fenton treatment, were found to be effective for the degradation of 2,4-dinitrophenol and removal of toxicity. Acc...

Two-pot experiments with ryegrass and wheat plants were conducted in a Cambic Arenosol to test the reliability of N fate predicted by incubation experiments previously performed, with the same soil, to assess potentially mineralizable nitrogen from six organic wastes (municipal solid waste compost, secondary pulp mill sludge, horn meal, poultry manure, solid phase from pig slurry and composted ...