article · Limnology and Oceanography Letters
Groundwater flows through subterranean estuaries before entering the sea, transporting nutrients that drive coastal primary production, water quality, and eutrophication. An analysis of more than 10,000 groundwater samples across 216 sites globally indicates that dissolved inorganic nitrogen, dissolved inorganic phosphorus, and dissolved organic nitrogen undergo complex chemical transformations within these subterranean zones. Fresh groundwater transport typically produces inorganic nitrogen and phosphorus while consuming organic nitrogen. Globally, median total submarine groundwater discharge releases approximately 5.4 teramoles of dissolved inorganic nitrogen, 2.6 teramoles of dissolved organic nitrogen, and 0.18 teramoles of dissolved inorganic phosphorus annually. Despite substantial natural variability, total submarine discharge fluxes likely exceed global riverine nutrient contributions. While fresh discharge delivers small amounts of newly introduced nutrients, saline discharge acts as a critical mechanism delivering recycled nutrients to coastal marine environments.
Coastal water quality, fisheries, and marine ecosystems depend heavily on nutrient balance to prevent harmful eutrophication. Showing that underground water flows transport more nutrients to the ocean than rivers fundamentally shifts how scientists and environmental managers view coastal inputs. Understanding these hidden subterranean pathways is essential for predicting coastal ocean health and responding effectively to land-based water pollution.
This work represents early-stage fundamental environmental research rather than an applied technology. Environmental consultancies, marine spatial planning authorities, and coastal water monitoring organisations could utilise these global flux models to improve environmental impact assessments and coastal nutrient budgets, but the abstract does not indicate a direct commercial application or technology product.
AI-generated from the published abstract. Always read the original work before citing.
Abstract Terrestrial groundwater travels through subterranean estuaries before reaching the sea. Groundwater‐derived nutrients drive coastal water quality, primary production, and eutrophication. We determined how dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), and dissolved organic nitrogen (DON) are transformed within subterranean estuaries and estimated submarine groundwater discharge (SGD) nutrient loads compiling > 10,000 groundwater samples from 216 sites worldwide. Nutrients exhibited complex, nonconservative behavior in subterranean estuaries. Fresh groundwater DIN and DIP are usually produced, and DON is consumed during transport. Median total SGD (saline and fresh) fluxes globally were 5.4, 2.6, and 0.18 Tmol yr −1 for DIN, DON, and DIP, respectively. Despite large natural variability, total SGD fluxes likely exceed global riverine nutrient export. Fresh SGD is a small source of new nutrients, but saline SGD is an important source of mostly recycled nutrients. Nutrients exported via SGD via subterranean estuaries are critical to coastal biogeochemistry and a significant nutrient source to the oceans.
This page summarises published work. The authoritative version sits with the publisher.
DOI: 10.1002/lol2.10390
Is something wrong with this record? Report it or request removal.
Discussion
Have you built on this work, tried to replicate it, or seen it applied in practice? Share what you know. Verified researchers and MARATTO™ domain experts can open a discussion, and any member can reply. Contributions are reviewed before they appear.
No discussion yet. Open the first thread.
New to MARATTO™? Create a free account.
