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| Titel |
Identification and characterisation of potential sources of nitrate pollution in the Marano Lagoon (Italy) applying a multi-isotope approach |
| VerfasserIn |
P. Saccon, A. Leis, A. Marca, J. Kaiser, L. Campisi, M. E. Böttcher, J. Savarino, P. Escher, A. Eisenhauer, J. Erbland |
| Konferenz |
EGU General Assembly 2012
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 14 (2012) |
| Datensatznummer |
250059917
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| Zusammenfassung |
| The isotopic composition of nitrate (δ15N, δ18O and Δ17O), boron (δ11B) and
water (δ2H and δ18O) were used to identify and characterize of multiple nitrate
pollution sources in the Marano Lagoon (Italy) and part of its catchment area. The
stable isotopes in nitrate measured by the denitrifier method have been adopted to
differentiate among nitrate coming from agriculture (synthetic and natural fertilizers),
airborne nitrate and nitrate from nitrification processes in soils. Boron isotopes have
been used to identify the impact of domestic wastewaters to the aquatic system
using the LA-MC-ICP-MS method. The combined use of NO3 and B isotopes has
proved to be an effective means in identifying multiple nitrate pollution sources
because these isotopes co-migrate in many environmental settings, their isotopes are
fractionated by different environmental processes, and because wastewater and fertilizers
may have distinct isotopic signatures for N and B. The stable isotopes of water
have been used to calculate mixing ratios between sea and fresh water as well as to
estimate the mean altitude of the recharge area of surface waters. Additionally, the
stable isotopes of sulphate (δ34S and δ18O) have been adopted to trace natural and
anthropogenic sources of sulphur in agricultural watersheds as well as in coastal systems. In
order to characterize the chemical composition of the different water types the
concentration of Ca2+, Mg2+, Na+, K+, NH4+, NO3-, NO2-, Cl-, Br-, SO42-,
HCO3-, PO43-, total phosphorus and total boron have been analyzed. Moreover, the
physicochemical parameters such as pH, electrical conductivity, dissolved oxygen,
salinity and temperature have been measured. To identify the origins and fate of
nitrate a water monitoring program was implemented in the Marano lagoon and part
of its catchment area. The water monitoring program involved the collection of
water samples from the lagoon, its tributary rivers, the groundwater up-welling line,
groundwater, sewer pipe and open sea on a quarterly interval from 2009 to 2010. |
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