AUTHOR=Fujita Koji , Shoji Jun , Sugimoto Ryo , Nakajima Toshimi , Honda Hisami , Takeuchi Masaru , Tominaga Osamu , Taniguchi Makoto TITLE=Increase in Fish Production Through Bottom-Up Trophic Linkage in Coastal Waters Induced by Nutrients Supplied via Submarine Groundwater JOURNAL=Frontiers in Environmental Science VOLUME=7 YEAR=2019 URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2019.00082 DOI=10.3389/fenvs.2019.00082 ISSN=2296-665X ABSTRACT=

Submarine groundwater is richer in nutrients compared to surface (river) water and therefore has been considered to be an essential component of biological production in marine coastal ecosystems. However, there has been no information on the effects of submarine groundwater on animals at high-order trophic levels such as fishes. Here, we show the first direct evidence that fish feeding and growth are elevated by submarine groundwater discharge (SGD) by on-site experiments and quantitative sampling. An experiment using cages moored on the sea bottom confirmed that juvenile marbled sole Pseudopleuronectes yokohamae obtained elevated levels of nutrition in the vicinity of SGD. Quantitative sampling at three sites with different hydrodynamic properties in coastal waters of the western North Pacific showed correspondence of high SGD with high biological production or biomass from producer to secondary consumers. These findings demonstrate that nutrients of terrestrial origin provided via submarine groundwater in coastal areas promote marine fish production.