Effects of CO₂ enrichment on benthic primary production and inorganic nitrogen fluxes in two coastal sediments.

ABSTRACT: Ocean acidification may alter the cycling of nitrogen in coastal sediment and so the sediment-seawater nitrogen flux, an important driver of pelagic productivity. To investigate how this perturbation affects the fluxes of NO_X^- (nitrite/nitrate), NH₄⁺ and O₂, we incubated estuarine sand and subtidal silt in recirculating seawater with a CO₂-adjusted pH of 8.1 and 7.9. During a 41-day incubation, the seawater kept at pH 8.1 lost 97% of its NO_X^- content but the seawater kept at pH 7.9 lost only 18%. Excess CO₂ increased benthic photosynthesis. In the silt, this was accompanied by a reversal of the initial NO_X^- efflux into influx. The estuarine sand sustained its initial NO<

SUBMITTER: Vopel K 

PROVIDER: S-EPMC5773597 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature