Nitrate sources and dynamics in alluvial aquifers assessed through multi-isotope fingerprinting and groundwater dating
type: Dataset
description: In spite of significant efforts over the last few decades in terms of source control of nitrogen input from French agriculture to ground- and surface water bodies, increasing tendencies of nitrate concentrations are still observed for numerous drinking water wells. This can be partly attributed to the inertia of the soil-groundwater system, with a slow nitrogen dynamics in the soil zone and groundwater residence times in the order of magnitude of years to tens of years even in superficial alluvial aquifer. This delay of effects of groundwater remediation measures is a serious drawback for attempts to reach the goals of the European Water Framework Directive, aiming to return to a good qualitative and quantitative status for European groundwater bodies till 2015. Here we present results of a regional study of nitrogen contamination of alluvial aquifers in the south-western Rhine Valley, France. Two drinking water wellfields show different behaviour since the late 1990ies with increasing nitrate contents for wells in the ancient alluvial terraces approaching the drinking water limit of 50 mg/L and slightly decreasing values for wells in young alluvial deposits close to the Rhine River. The use of a combination of stable isotopes, N and O isotopes of the nitrate ions, O and H of water, isotopes of dissolved B and Sr, with groundwater dating methods (CFCs, SF6) gives insight in the nature and dynamics of nitrate contamination of such alluvial aquifers. Potential nitrogen sources (mineral fertilisers, manure, and domestic waste water) were analysed together with the target wells and surrounding ground- and surface waters. The results reveal mean groundwater residence times around 8 to 10 years for the wells in the ancient alluvial sediments and isotope fingerprints compatible with oxidation of organic nitrogen or ammonia but not with mixing with domestic wastewater. Groundwaters in the young alluvial deposits of the Rhine River are mostly contaminated by local CFC input …
landing page: Goldschmidt Conference 2014
keyword: conference-papers
keyword: contamination
keyword: groundwater
keyword: infoeu-reposemanticsconferenceobject
keyword: isotopes
keyword: nitrate
keyword: residence-time
keyword: sdemcgenvironmental-sciencesglobal-changes
keyword: sdustugcsciences-of-the-universe-physicsearth-sciencesgeochemistry
issued: 2026-05-05T11:11:29.608114
modified: 2026-05-05T11:11:29.608118
language: en
contact point: Organization
  fn: CCSD

test_moissonnage_selune
type: Agent

Nitrate sources and dynamics in alluvial aquifers assessed through multi-isotope fingerprinting and groundwater dating
type: Distribution
format: HTML
access URL: https://brgm.hal.science/hal-00991428
issued: 2026-05-05T11:11:29.612002
modified: 2026-05-05T11:11:29.596735