Bivalve δ15N isoscapes provide a baseline for urban nitrogen footprint at the edge of a World Heritage coral reef

MARINE POLLUTION BULLETIN

卷:152

Article

Thibault, M.^1,2  Duprey, N.³  Gillikin, D. P.⁴  Thebault, J.¹  Douillet, P.⁵  Chauvaud, L.¹  Amice, E.¹  Munaron, J. M.¹  Lorrain, A.¹ 

[1] Univ Brest, CNRS, IRD, Ifremer,LEMAR, F-29280 Plouzane, France

[2] Univ Reunion, CNRS, IRD, UMR ENTROPIE,Lab Excellence Labex CORAIL,Inst Rec, BP A5, Noumea 98848, New Caledonia

[3] Max Planck Inst Chem, Dept Climate Geochem, Otto Hahn Inst, Hahn Meitner Weg 1, D-55128 Mainz, Germany

[4] Union Coll, Dept Geol, Schenectady, NY 12308 USA

[5] Aix Marseille Univ, Univ Toulon, Mediterranean Inst Oceanog MIO UMR110, CNRS INSU,IRD, F-13288 Marseille, France

关键词: delta N-15;    Isoscape;    Bivalve;    Eutrophication;    Coral reefs;    Heritage sites;   

DOI  :  10.1016/j.marpolbul.2019.110870

来源: Elsevier

【 摘 要 】

Eutrophication is a major threat to world's coral reefs. Here, we mapped the distribution of the anthropogenic nitrogen footprint around Noumea, a coastal city surrounded by 15,743 km(2) of UNESCO listed reefs. We measured the delta N-15 signature of 348 long-lived benthic bivalves from 12 species at 27 sites and interpolated these to generate a delta N-15 isoscape. We evaluated the influence of water residence times on nitrogen enrichment and predicted an eutrophication risk at the UNESCO core area. Nitrogen isoscapes revealed a strong spatial gradient (4.3 to 11.7 parts per thousand) from the outer lagoon to three highly exposed bays of Noumea. Several protected reefs would benefit from an improved management of wastewater outputs, while one bay in the UNESCO core area may suffer a high eutrophication risk in the future. Our study reinforces the usefulness of using benthic animals to characterize the anthropogenic N-footprint and provide a necessary baseline for both ecologists and policy makers.

【 授权许可】

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