کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4425448 | 1309104 | 2011 | 8 صفحه PDF | دانلود رایگان |
Increased reactive nitrogen (Nr) deposition due to expansion of agro-industry was investigated considering emission sources, atmospheric transport and chemical reactions. Measurements of the main inorganic nitrogen species (NO2, NH3, HNO3, and aerosol nitrate and ammonium) were made over a period of one year at six sites distributed across an area of ∼130,000 km2 in southeast Brazil. Oxidized species were estimated to account for ∼90% of dry deposited Nr, due to the region’s large emissions of nitrogen oxides from biomass burning and road transport. NO2-N was important closer to urban areas, however overall HNO3-N represented the largest component of dry deposited Nr. A simple mathematical modeling procedure was developed to enable estimates of total Nr dry deposition to be made from knowledge of NO2 concentrations. The technique, whose accuracy here ranged from <1% to 29%, provides a useful new tool for the mapping of reactive nitrogen deposition.
► First estimates in Brazil of nitrogen deposition fluxes based on measurements.
► New technique for nitrogen deposition determination using measurements and modeling.
► Nitrogen deposition is predominantly in oxidized forms due to biomass burning.
► HNO3 largest component of nitrogen deposition in a tropical agro-industrial region.
► Increased nitrogen deposition in rural regions due to removal from urban plumes.
Journal: Environmental Pollution - Volume 159, Issue 5, May 2011, Pages 1190–1197