KARST · KArstic submarine fReshwater Springs
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2022-09-01 → 2024-08-31
- EU contribution
- €148,049
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
KArstic submarine fReshwater Springs
Groundwater acts as a critical link between onshore and offshore environments, connecting freshwater systems to the saline oceans. Coastal aquifers are increasingly under pressure due to expanding coastal populations and growing variability in precipitation and recharge. As freshwater resources in these areas become more scarce, the threat of saltwater intrusion intensifies, and offshore freshened groundwater becomes a critical resource. Meteoric groundwater flow underneath the ocean, with coastal and submarine freshwater springs, as well as the inflow of saltwater into onshore aquifers, are common phenomena observed in coastal regions across the world. Nonetheless, the groundwater flow from land underneath and into the sea and the recharge of offshore groundwater resources remains veiled from our eyes and especially urban areas pose unique challenges for remote sensing techniques to characterise flow pathways for proper management. Groundwater extraction on land and reduction of SGD below a critical limit can induce the inflow of saltwater into the aquifer. In karstic coastal aquifers, submarine groundwater springs are important indicators of the extremely heterogeneous groundwater distribution in the subsurface, where turbulent and fast-flowing groundwater through conduits and caves often results in variable spring discharge and water quality. Despite the importance of submarine groundwater discharge in global hydrology, localizing submarine springs and predicting saltwater inflow into coastal aquifers remains difficult. The aim of this action was to 1)develop new methodological approaches to detect, characterise and quantify submarine springs 2)characterise the architecture of amphibious karst groundwater systems and determine the offshore recharge capabilities 3)to assess the impact of SGD seafloor morphology, habitats, and seagrass distribution
Data: CORDIS, © European Union
Project objective
Submarine groundwater discharge (SGD) is the flow of fresh or recirculated groundwater into the ocean. This process introduces substantial amounts of nutrients to coastal areas, which significantly influences ecological systems. In karstic settings SGD dominantly occurs from submarine springs that manifest as point source discharge sites. Their identification generally relies on sea-surface changes (e.g. visual sea-surface anomalies or changes in sea-surface temperature) and is therefore confined to shallow areas with high discharge rates. As a result the distribution of offshore freshwater springs in karstic environments, which is crucial for determining the architecture and dissemination of offshore groundwater systems, is usually poorly constrained. Similarly, the negative effects of groundwater springs on seagrass diversity and biomass have been investigated at individual springs but have not been characterised over larger areas. This proposal focuses on the identification, characterisation and distribution of submarine springs and their influence on local ecosystems in karstic environments. KARST will make use of state of the art geophysical and remote sensing techniques for optimal imaging at various depths. In the shallow coastal areas (<~5 m), unmanned aerial vehicles equipped with multispectral and thermal infrared cameras will be used to simultaneously image and correlate biological habitats and sea-surface anomalies related to submarine springs. In deeper areas, a newly developed geoelectric system from the University of Kiel in combination with multibeam water column imaging techniques will provide insight into the physical behaviour of the water column as well as salinity and seagrass distribution around springs. All techniques will be guided by biological sampling and flow rate measurements, which will not only help to determine the ecological effects of SGD but will also provide valuable knowledge on the architecture of karstic groundwater systems.
Original text from CORDIS.
Participants
- UNIVERSITA TA MALTA · MSIDACoordinatorMalta
Links
Data: CORDIS, © European Union