The reduction of ammonia (NH3) emissions is urgently needed due to its role in aerosol nucleation and growth causing haze formation during its conversion into ammonium (NH4(+)). However, the relative contributions of individual NH3 sources are unclear, and debate remains over whether agricultural emissions dominate atmospheric NH3 in urban areas. Based on the chemical and isotopic measurements ...

To meet the high quality standard of receiving water, the coagulation process using polyferric chloride (PFC) was used to further improve the water quality of effluent from wastewater treatment plants. Uniform design (UD) coupled with response surface methodology (RSM) was adopted to assess the effects of the main influence factors: coagulant dosage, pH and basicity, on the removal of total org...

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...

Futile transmembrane NH3/NH4(+) cycling in plant root cells, characterized by extremely rapid fluxes and high efflux to influx ratios, has been successfully linked to NH3/NH4(+) toxicity. Surprisingly, the fundamental question of which species of the conjugate pair (NH3 or NH4(+)) participates in such fluxes is unresolved. Using flux analyses with the short-lived radioisotope (13)N and electrop...

Animal manures are a valuable resource, providing readily available plant nutrients ; however, runoff from lands receiving animal manure has been shown to contribute to water pollution. Understanding the loss of nutrients from slow release fertilizers, such as animal manure, after application is critical in determining and designing practices to reduce and/or control the temporal availability a...

To date, few studies are conducted to quantify the effects of reduced ammonium (NH4+) and oxidized nitrate (NO3-) on soil CH4 uptake and N2O emission in the subtropical forests. In this study, NH4Cl and NaNO3 fertilizers were applied at three rates: 0, 40 and 120 kg N ha(-1) yr(-1). Soil CH4 and N2O fluxes were determined twice a week using the static chamber technique and gas chromatography. S...

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...

OBJECTIVE The present study aimed to assess the nitrogen (N) use efficiency of acidified pig slurry for regrowth yield and its environmental impacts on perennial ryegrass swards. METHODS The pH of digested pig slurry was adjusted to 5.0 or 7.0 by the addition of sulfuric acid and untreated as a control. The pig slurry urea of each treatment was labeled with 15N urea and applied at a rate of 2...

Soil cation-exchange capacity (CEC) is often determined by NH4 saturation, using a 1M solution of NH4C2H3O2 at pH 7. A study was conducted to ascertain whether this determination can be performed by employing a simple diffusion technique previously developed for direct inorganic-N analysis of soils. Values obtained for 10 diverse Illinois surface soils following overnight NH4 saturation were co...

This study examines the role of tree canopies in processing atmospheric nitrogen (Ndep ) for four forests in the United Kingdom subjected to different Ndep : Scots pine and beech stands under high Ndep (HN, 13-19 kg N ha(-1)  yr(-1) ), compared to Scots pine and beech stands under low Ndep (LN, 9 kg N ha(-1)  yr(-1) ). Changes of NO3 -N and NH4 -N concentrations in rainfall (RF) and throughfall...