Flood survey of nitrate behaviour using nitrogen isotope tracing in the critical zone of a French agricultural catchment

doi:https://doi.org/10.1016/j.crte.2015.06.002

Article10.1016/j.crte.2015.06.002

Flood survey of nitrate behaviour using nitrogen isotope tracing in the critical zone of a French agricultural catchment

Alexia Paul,Issam Moussa,Virginie Payre,Anne Probst,Jean‐Luc Probst-2015-07-21-Comptes Rendus Géoscience

19

TL;DRAbstract

Measurements of δ 15 N–NO 3 – were taken in a highly flood-responsive agricultural catchment in the southwest of France to trace the sources and transfer pathways of nitrates during flood events. From January to March 2013, surface water samples were collected every week at the outlet, and four floods were sampled with a high resolution. Sampling was also performed in surface waters and sand lenses from the rest of the basin to trace nitrate sources and processes spatially. Nitrate extractions were performed using a method based on the solubility difference between inorganic salts and organic solutions. The δ 15 N values were in the range of surface water contaminated by N-fertilisers. Depending on the hydroclimatic event, nitrates resulted from a combination of sources and processes. At the start of the floods, the values of δ 15 N–NO 3 – and nitrate concentrations were low, demonstrating the dilution of water with rainwater. During a second phase, the nitrate concentration and the δ

Chat with Paper

AI Agents for this Paper

Measurements of δ 15 N–NO 3 – were taken in a highly flood-responsive agricultural catchment in the southwest of France to trace the sources and transfer pathways of nitrates during flood events. From January to March 2013, surface water samples were collected every week at the outlet, and four floods were sampled with a high resolution. Sampling was also performed in surface waters and sand lenses from the rest of the basin to trace nitrate sources and processes spatially. Nitrate extractions were performed using a method based on the solubility difference between inorganic salts and organic solutions. The δ 15 N values were in the range of surface water contaminated by N-fertilisers. Depending on the hydroclimatic event, nitrates resulted from a combination of sources and processes. At the start of the floods, the values of δ 15 N–NO 3 – and nitrate concentrations were low, demonstrating the dilution of water with rainwater. During a second phase, the nitrate concentration and the δ

Keywords

NitrateHydrology (agriculture)Environmental scienceSurface waterDrainage basinGroundwaterSoil waterEnvironmental chemistry

Chat

Click to start Chat