Fresh groundwater discharge insignificant for the world's oceans but important for coastal ecosystems.
Where this comes from
- Record sourced from PubMed, PMID 32152309.
- Also identified by DOI 10.1038/s41467-020-15064-8 and PMC identifier 7062736.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The flow of fresh groundwater may provide substantial inputs of nutrients and solutes to the oceans. However, the extent to which hydrogeological parameters control groundwater flow to the world's oceans has not been quantified systematically. Here we present a spatially resolved global model of coastal groundwater discharge to show that the contribution of fresh groundwater accounts for ~0.6% (0.004%-1.3%) of the total freshwater input and ~2% (0.003%-7.7%) of the solute input for carbon, nitrogen, silica and strontium. However, the coastal discharge of fresh groundwater and nutrients displays a high spatial variability and for an estimated 26% (0.4%-39%) of the world's estuaries, 17% (0.3%-31%) of the salt marshes and 14% (0.1-26%) of the coral reefs, the flux of terrestrial groundwater exceeds 25% of the river flux and poses a risk for pollution and eutrophication.