Temporal variability of benthic-pelagic coupling in shallow enclosed environment: A case study with eutrophying shrimp ponds
|Author(s)||Hochard Sébastien1, 2, Royer Florence1, Hubert Morgane1, 3, Lemonnier Hugues1|
|Affiliation(s)||1 : IFREMER ,LEAD, BP 32078, 98897, Nouméa Cedex, New Caledonia
2 : SOPOMER, BP 1605, 98713, Papeete, French Polynesia
3 : IFREMER, LEP, Centre Bretagne, ZI de la Pointe du Diable, CS 10070, 29280, Plouzané, France
|Source||Marine Environmental Research (0141-1136) (Elsevier BV), 2019-04 , Vol. 146 , P. 46-56|
|Keyword(s)||Tropical aquaculture, Shrimp, Eutrophication, Benthic-pelagic coupling, Microphytobenthos, Bioturbation|
The evolution of benthic pelagic coupling was followed in two semi-intensive shrimp ponds in New Caledonia, with a special emphasis on the role of microphytobenthos (MPB). Three distinct periods could be identified. During the first period, MPB activity led to relative decoupling between the water column and the sediment, both compartments being autotrophic with low nutrients exchanges. During the second period, the sediment operated at the edge of a functional switch between autotrophy and heterotrophy. The amplitude of nutrient fluxes depended of the pool considered (DIN, DIP) and showed light dark variation. In the last period, sediment switched to heterotrophy with the establishment of benthic-pelagic coupling concomitantly to a massive sediment resuspension due to the shrimp activity. These findings should be considered for the management of aquaculture ponds and shallow enclosed water bodies.