Dataset for analyzing and modelling the eutrophication processes in groundwater-coastal lagoon systems: The La Pletera lagoons case study (NE Spain)

A comprehensive hydrogeological report was conducted to determine the origin, occurrence and processes affecting ni-trogen in a Mediterranean coastal aquifer-lagoon system. Wa-ter levels, hydrochemical and isotopic data was gathered dur-ing a 4-year period in the La Pletera salt marsh area (NE Spain). They were collected from the alluvial aquifer, two natural lagoons and four other permanent lagoons excavated during a restoration process (in 2002 and 2016), two wa-tercourses (the Ter River and the Ter Vell artificial channel), 21 wells (considering six of them for groundwater sampling) and the Mediterranean Sea. Potentiometric surveys were carried out seasonally, however twelve-monthly campaigns (from November 2014 to October 2015), and nine seasonal campaigns (from January 2016 to January 2018) were con-ducted for hydrochemical and environmental isotopes analy-ses. The evolution of the water table was analysed for each well, and potentiometric maps were plotted to determine the relationship between the aquifer and the lagoons, sea, water- courses, and groundwater flow. Hydrochemical data included physicochemical data measured in situ (temperature, pH, Eh, dissolved oxygen, and electrical conductivity), major and mi-nor ions (HCO3 -, CO3 2 -, Cl -, SO4 2 -, F -, Br-, Ca2+ , Mg2+ , Na +, and K +), and nutrients (NO2 -, NO3 -, NH4 +, Total Nitrogen (TN), PO4 3 -, and Total Phosphorus (TP)). Environmental iso-topes included stable water isotopes ( 818 O and 8D), nitrate (815NNO3 and 818ONO3) and sulphate isotopes (834SSO4 and 818OSO4). Water isotopes were analysed for all campaigns, however, nitrate and sulphate isotopes water samples were only analysed in some particular surveys (November and De-cember 2014; January, April, June, July and August 2015). Additionally, two more surveys for sulphate isotopes were conducted in April and October of 2016. The data gener-ated through this research may be used as a starting point to analyse the evolution of these recently restored lagoons, and their future responses to global change. In addition, this dataset may be used to model the hydrological and hydro -chemical behaviour of the aquifer.(c) 2023 Published by Elsevier Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

Automated summary

A comprehensive hydrogeological report was conducted to determine the origin, occurrence, and processes affecting nitrogen in a Mediterranean coastal aquifer-lagoon system. Data on water levels, hydrochemical and isotopic measurements were collected from various sources including wells, lagoons, watercourses, and the Mediterranean Sea. By analyzing the data, the researchers aimed to understand the relationship between the aquifer and the lagoons, as well as to model the hydrological and hydrochemical behavior of the aquifer.