Nitrogen enrichment offsets direct negative effects of ocean acidification on a reef-building crustose coralline alga.

ABSTRACT: Ocean acidification (OA) and nutrient enrichment threaten the persistence of near shore ecosystems, yet little is known about their combined effects on marine organisms. Here, we show that a threefold increase in nitrogen concentrations, simulating enrichment due to coastal eutrophication or consumer excretions, offset the direct negative effects of near-future OA on calcification and photophysiology of the reef-building crustose coralline alga, Porolithon onkodes Projected near-future pCO₂ levels (approx. 850 µatm) decreased calcification by 30% relative to ambient conditions. Conversely, nitrogen enrichment (nitrate + nitrite and ammonium) increased calcification by 90-130% in ambient and high pCO₂ treatments, respectively. pCO₂ and nitrogen enrich

SUBMITTER: Johnson MD 

PROVIDER: S-EPMC6083234 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature