• DOI:10.4319/lo.2003.48.6.2266
• Corpus ID: 18175345

Nitrate uptake in the scleractinian coral Stylophora pistillata

@article{Grover2003NitrateUI,
  title={Nitrate uptake in the scleractinian coral Stylophora pistillata},
  author={Renaud Grover and Jean François Maguer and Denis Allemand and Christine Ferrier‐Pag{\`e}s},
  journal={Limnology and Oceanography},
  year={2003},
  volume={48}
}

• R. Grover, J. Maguer, +1 author C. Ferrier‐Pagès
• Published 1 November 2003
• Environmental Science
• Limnology and Oceanography

We assessed the uptake rates of nitrate by the scleractinian coral Stylophora pistillata by following 15N from seawater into the coral tissue. Two sets of corals were first prepared, with “nitrate‐enriched” corals grown in 5 µmol L−1 NO3− and control corals grown in ≤µmol L−1 NO3−. Uptake rates at 0.3 and 3 µmol L−1 [15N]NO3− were then measured. Most of the %15N enrichment occurred in the zooxanthellae fraction. Uptake rates were not significantly different between nitrate‐enriched and control corals, suggesting that they were not dependent on a nitrate acclimation. These rates increased with the in situ nitrate concentration and varied from 1.2 ± 0.2 ng h−1 cm−2 N to 6.1 ± 1.1 ng h−1 cm−2 N in the algal fraction at 0.3 and 3 µmol L−1 [15N]NO3−, respectively. In a second experiment, two sets of corals were prepared, with “ammonium‐enriched” corals grown in 5 µmol L−1 NH4+ and control corals grown in <1 µmol L−1 NH4+. Uptake rates at 3 µmol L−1 [15N]NO3− were measured. These rates were significantly lower with high NH4+ concentrations in seawater. In the algal fraction, they ranged from 0.1 to 0.6 ng 14 h−1 cm−2 N in NH4+‐enriched corals and from 2.2 to 4.5 ng h−1 cm−2 N in control corals. Nitrate can therefore be considered as an important source of nitrogen for corals, at least when ammonium concentrations are low in seawater.