Subterreanean estuaries: A source or sink of contaminants of emerging concern to the coastal ocean?

Project Information

STE CECs

Grant agreement ID: 101026629

DOI

10.3030/101026629

Project closed

EC signature date 24 March 2021

Start date 1 September 2021

End date 31 August 2023

Funded under

• EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions

Total cost

€ 203 852,16

EU contribution

€ 203 852,16

Coordinated by

GOETEBORGS UNIVERSITET
Sweden

Periodic Reporting for period 1 - STE CECs (Subterreanean estuaries: A source or sink of contaminants of emerging concern to the coastal ocean?)

Reporting period: 2021-09-01 to 2023-08-31

Summary of the context and overall objectives of the project

The MSCA project “Subterranean estuaries: A source or sink of contaminants of emerging concern to the coastal ocean?” examines the role and drivers of submarine groundwater discharge (SGD) as a source of contaminants of emerging concern (CECs; e.g. pharmaceuticals, industrial chemicals, pesticides) to the coastal ocean. SGD, which refers to groundwater flowing to the coastal ocean is understudied in many regions of the world, despite its critical contribution to coastal water and chemical budgets. For instance, previous studies have linked SGD-derived nutrient pollution to eutrophication, ocean acidification, and the proliferation of harmful algal blooms in coastal areas. Recently, SGD has also been identified as a source of CECs as well. CECs can be toxic to aquatic organisms and contribute to antimicrobial resistance, even in trace quantities. Thus, understanding the source(s) and processes that influence their concentrations in the environment is critical.

The coastal aquifer, also known as the subterranean estuary (STE) is a biogeochemically active zone that SGD travels through before flowing into coastal waters. This project broadly takes a multi-pronged approach to better understand the importance of SGD as a source of CECs and the drivers of CEC biogeochemistry in the STE.

The objectives of this MSCA were to answer the following research questions: (1) Does eutrophication drive the release of CECs from STEs? (2) Does the nitrogen biogeochemical cycle drive CEC transformations in STEs? And (3) Can we model reactive CEC transport within CECs?

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

This project included 3 work packages (WPs) and additional career development objectives. WP1, WP2, and WP3 integrated field, lab, and modeling approaches, respectively, to better understand SGD as a source of CECs to the coastal ocean and the role of coastal aquifer biogeochemical interactions and substrate material on CEC attenuation or amplification prior to discharge as SGD. The fellow was based at the University of Gothenburg (Gothenburg, Sweden) working with Prof. Isaac Santos and completed a secondment with Prof. Nils Moosdorf at the Leibniz Centre for Tropical Marine Research (ZMT) in Bremen, Germany. He presented three conference presentations, published one peer-reviewed publication (with one currently undergoing review, and another two in preparation), and published new software. In addition, the fellow exceeded additional career training objectives during the fellowship, including teaching a course, applying for four grants, supervision of one MS student and co-supervision of one MS and one PhD student, giving >4 seminar talks, and contributing to >3 community engagement and outreach events. During the fellowship, the fellow was also a co-author on four large meta-analysis publications in the field of SGD (two have been accepted/published, two are currently undergoing peer-review). All results from this MSCA are presented or will be presented in open-access peer-reviewed publications and datasets, which are also referenced on the project-s public website.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

This MSCA presents some of the first research investigating the role of SGD as a source of CECs and how environmental conditions such as pH and oxygen concentrations may reduce or amplify CEC concentrations in coastal waters. Research results further demonstrate the importance of SGD on coastal waters and ecosystems. Broader impacts from this MSCA include the increased understanding of the role SGD plays in CEC delivery to the coast, as well as how CECs partition in groundwater vs. surface water in coastal environments. These results can inform EU policy objectives and regulatory frameworks on CECs in the aquatic environment.

Progress beyond the state of the art from this project include: (1) improved understanding of processes and conditions driving CEC attenuation in the coastal aquifer, (2) generation of first global model of antibiotics to the coastal ocean via SGD, and (3) the first research to apply deep learning approaches in the context of SGD, facilitating significantly more accessible methods for predicting SGD tracer data.

Conceptual diagram of sources of CECs to the coastal ocean via SGD