README  Mar Menor Submarine Groundwater Discharge General Dataset

Version: First Release (v1)
Location: Mar Menor Coastal Lagoon, SE Spain
Sampling Period: March 2021  May 2022


-------Overview------- 

First release of the Mar Menor SGD general dataset.
This dataset contains detailed information on stream water, groundwater, lagoon water, and soils collected in the Mar Menor coastal lagoon (SE Spain) from March 2021 to May 2022. The data includes physicochemical parameters (e.g., temperature, salinity, pH, dissolved oxygen), radionuclide activities (e.g., Ra-223, Ra-224, Ra-226, Ra-228), dissolved nutrient concentrations (NO3-, NO2-, NH4+, Si(OH)4, PO43-, TDN), dissolved organic carbon concentrations (DOC),  microbial parameters (e.g., total bacterial abundance, HNA fraction, 3H-leucine incorporation rates), and mercury chemical species (total dissolved mercury and dissolved methylmercury). 

This dataset was used to estimate the magnitude of different SGD pathways, including pollutant fluxes in the lagoon, and interpret their impact on microbial communities.

-------File Structure-------

The dataset is provided as a README file, including instructions on the use and filtering of the data, and an Excel workbook with the dataset, including the following sheets:
		How to Cite: Citation guidelines for users referencing this dataset.
		Data: Core dataset with all recorded parameters per sample.
		Variables Description: Description and units of the variables in the Data sheet.

-------Use & Filtering-------

Not all variables were used in all publications (see Associated Publications). Depending on which variable(s) you use, please cite the specific paper(s) where those data were applied.


Samples can be filtered according to the publication in which they were used. The drop-down menu in the Study variable (Column A) allows for selection.


-------Associated Publications-------

On SGD pathways estimation using Ra isotopes:
Rodriguez-Puig et al. (2025). Seasonality of submarine groundwater discharge pathways in a coastal lagoon revealed by radium isotopes: The importance of porewater exchange in summer. Journal of Hydrology, 133616. https://doi.org/10.1016/j.jhydrol.2025.133616 

On SGD and Microbial Communities:
Romano-Gude et al. (2025). Under revision in Molecular Ecology.

On SGD-derived mercury fluxes:
Lavergne et al. (2025). Unveiling hidden mercury and methylmercury sources: the role of submarine groundwater discharge in coastal lagoons. Environmental Science and Technology.

On SGD-derived nutrient fluxes:
Rodriguez-Puig et al. (in prep).

-------Funding-------

This research was supported by Agencia Estatal de Investigacin (AEI), Spanish Ministry of Science and Innovation through:
		OPAL project (PID2019-110311RB-CXX)
		WINDERS project (TED2021-130710B-I00)
               MINIOM project (PID2022-142480NB-I00)
               PATCHI project (CNS2023-144233)


