High-resolution inventory of NO emissions from agricultural soils over the Ile-de-France region

Arable soils are a significant source of nitric oxide (NO), a precursor of tropospheric ozone, and thereby contribute to ozone pollution. However, their actual impact on ozone formation is strongly related to their spatial and temporal emission patterns, which warrant high-resolution estimates Here, we combined an agro-ecosystem model and geo-referenced databases to map these sources over the 12 000 km(2) administrative region surrounding Paris, France, with a kilometric level resolution The six most frequent arable crop species were simulated, with emission rates ranging from 14 kg N-NO ha(-1) yr(-1) to 11.1 kg N-NO ha(-1) yr(-1). The overall emission factor for fertilizer-cleaved NO emissions was 1.7%, while background emissions contributed half of the total NO efflux. Emissions were strongly seasonal, being highest in spring due to fertilizer inputs They were mostly sensitive to soil type, crops' growing season and fertilizer N rates. (C) 2009 Elsevier Ltd. All rights reserved.