%0 Journal Article %T Origin and fate of phosphorus in the Seine watershed (France): Agricultural and hydrographic P budgets %+ Laboratoire d'étude des transferts en hydrologie et environnement (LTHE) %+ Structure et fonctionnement des systèmes hydriques continentaux (SISYPHE) %A Nemery, Julien %A Garnier, Josette %< avec comité de lecture %@ 2169-8953 %J Journal of Geophysical Research: Biogeosciences %I American Geophysical Union %V 112 %N G3 %P G03012 %8 2007 %D 2007 %R 10.1029/2006JG000331 %Z Sciences of the Universe [physics]/Earth Sciences/Geochemistry %Z Sciences of the Universe [physics]/Earth Sciences/HydrologyJournal articles %X Phosphorus (P) sources (point and diffuse) in the human-impacted Seine basin (64,840 km2) were evaluated for the year 2000. An agricultural P budget showed that fertilizers represented 59% (20–25 kgP ha−1) of P inputs to the soils. A P surplus (2.5 kg P ha−1 y−1) contributed to P enrichment of the agricultural soils whose stocks amounted to 1800–5000 kgP ha−1. A hydrographic P budget showed that runoff (0.39–0.51 kgP ha−1) dominated the diffuse sources. These losses represented a very low percentage (0.01%) of the P stocks in soils and contributed to 19–25% of the total P inputs to the drainage network. Point sources remained the main source of P (75–81%), particularly in the downstream urbanized zone. Phosphorus retention in the river drainage network accounted for 9–15% of the total P inputs, indicating that it must not be ignored in large river P budget calculations. The Seine basin exported 8000 tP y−1 (44% as particulate P) to its estuary. The annual mean particulate P in suspended sediment at the outlet (2.9 gP kg−1) was fourfold greater than in headwaters and in rural zones. The similar increase of the particulate inorganic P/particulate organic P ratio in suspended sediment along the river continuum clearly indicated the increasing pressure of point sources. The close relation between P content of suspended sediment during the high-flow period and the P content of agricultural soils resulted in proposing a novel method to calculate the PP losses from runoff. %G English %2 https://insu.hal.science/insu-00387866/document %2 https://insu.hal.science/insu-00387866/file/2006JG000331.pdf %L insu-00387866 %U https://insu.hal.science/insu-00387866 %~ INSU %~ INSTITUT-TELECOM %~ UNIV-SAVOIE %~ UPMC %~ EPHE %~ UGA %~ CNRS %~ UNIV-GRENOBLE1 %~ INPG %~ IRSTEA %~ ACL %~ GIP-BE %~ PSL %~ AGREENIUM %~ SORBONNE-UNIVERSITE %~ TEST-DEV %~ INRAE %~ ENSMP-PSL %~ EPHE-PSL %~ USMB-COMUE %~ SU-TI %~ ALLIANCE-SU