A Single Law to Describe Atmospheric Nitrogen Bulk Deposition versus Rainfall Amount: Inputs at the Seine River Watershed Scale     

Garban  B.  Motelay-Massei  A.  Blanchoud  H.  Ollivon  D. 《Water, air, and soil pollution》2004,155(1-4):339-354

Atmospheric nitrogen species (NH₄-N and (NO₃+NO₂)-N) were determined in weekly samples of atmospheric bulk deposition (dry plus wet), collected in France at seven sites over the course of a year. Rural, semi-rural and industrialised-urban sites were chosen in the Seine river watershed from the Seine estuary to upstream from Paris. Mean NH₄-N concentrations varied from 0.7 to 1.7 mg L^-1. Mean (NO₃+NO₂)-N concentrations were approximately 0.5 mg L^-1 for all sites except Paris (0.7 mg L^-1), which has a local impact on the fallout contamination from urban emissions. The relation between concentration and rainfall amount obeys a power law, in the form of y = ax ^b. When the nitrogen sources are very local, this relationship turns into a dilution law. Annual atmospheric nitrogen deposition (NH₄-N+(NO₃+NO₂)-N) was calculated and varied from 7.8 kg ha^-1 yr^-1 in the neighbourhood of a rural town to 17.3 kg ha^-1 yr^-1 in a very industrialised harbour. 58% of the atmospheric nitrogen deposition occurred during ‘spring + summer’ period. The total nitrogen atmospheric input to the Seine estuary, via direct deposition + indirect input via the watershed, was estimated to about 5% of the total nitrogen load within the Seine river basin.  相似文献   

Triazines in the Marne and the Seine Rivers (France) Longitudinal Evolution and Flows     

Garmouma  Mourad  Blanchoud  Hélène  Teil  Marie-Jeanne  Blanchard  Martine  Chevreuil  Marc 《Water, air, and soil pollution》2001,132(1-2):1-17

The transportation pathways of triazines were investigatedfrom their origins onwards, in the Marne and the Seine rivers(France). According to the 1991 survey, the highest total triazine concentration levels (956 ng L^-1) were found in the river Marne: 580 ng L^-1 for atrazine and 200 ng L^-1 for simazine, in relation with agricultural practices.The total triazine levels reached 829 ng L^-1 in the riverSeine. The other triazines remained low, from 5 to 75 ng L^-1. The triazine fluxes were 226 and 404 kg for a 118 d period in the Marne and the Seine rivers, respectively. Out of the treatment period, triazine peaks were related to riverflows with a 48 hr delay between the peak and the top of theflood. After herbicide treatment, peak concentrations wereclosely related with the precipitations. Concerning theriver Marne tributaries, highest atrazine concentrationswere found in June, in those which drained the vineyardarea. In January, the concentrations were higher inperiurban areas underlining their contribution to theherbicide inputs in the rivers. On the whole, the ratio oftriazines transported in the two rivers represented 0.2%of the total amount applicated annually on their catchment basins.  相似文献