Pelagic stocks and carbon and nitrogen uptake in a pearl farming atoll (Ahe, French Polynesia)

MARINE POLLUTION BULLETIN

卷:167

Article

Rodier, Martine^1,3  Pinazo, Christel¹  Seceh, Claire¹  Varillon, David² 

[1] Univ Toulon & Var, Aix Marseille Univ, IRD, CNRS,Mediterranean Inst Oceanog MIO,UM 110, F-13288 Marseille, France

[2] Inst Rech Dev, US IMAGO 191, BP A5, Noumea 98848, New Caledonia

[3] Univ Polynesie Francaise, UMR EIO 241, Inst Rech Dev, IRD,ILM,Infremer, BP 6570, F-98702 Tahiti, French Polynesi, France

关键词: Nitrogen uptake;    Primary production;    Phytoplankton composition;    Atoll lagoon;    Pearl farming;    French Polynesia;   

DOI  :  10.1016/j.marpolbul.2021.112352

来源: Elsevier

【 摘 要 】

This study reports the first measurements of nitrogen uptake and new data on carbon fixation (N-15/C-13 incorporation) for two size-fractionated phytoplankton (<2 mu m and >2 mu m), on organic matter, and phytoplankton stocks in Ahe lagoon. Data were collected between November and December 2017, during the hot season with prevailing trade winds. Ammonium and nitrate uptake data (7.58 to 39.81 and 1.80 to 21.43 mu mol N m(-3) h(-1), respectively) suggest a rapid turn-over of N-nutrients in the water column and show that primary production was largely sustained by recycled nitrogen providing 68% of the pelagic N demand. These results highlight the spatial heterogeneity of the measured processes linked to the local hydrodynamics, exhibiting higher regenerated production in the more exploited southwestern part of the lagoon and a higher proportion of new production in the north. Intense nutrient recycling appears to promote nanophytoplankton production which is critical for pearl oyster growth.

【 授权许可】

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