DIAPALIS 2

Name: DIAPALIS 2
Start: 2001-12-10
End: 2001-12-21
Location: Coral Sea

Type	Oceanographic cruise
Set	This cruise is part of the set DIAPALIS
Ship	Alis
Ship owner	IRD
Dates	10/12/2001 - 21/12/2001
Chief scientist(s)	LE BOUTEILLER Aubert
	INSTITUT MÉDITERRANÉEN D'OCÉANOLOGIE - UMR 7294 UMR IRD 235 - MARSEILLE 163 avenue de Luminy Bâtiment Méditerranée 13288 Marseille Cedex 9 +33(0)4 86 09 05 00 https://www.mio.osupytheas.fr/fr/mio/presentation
DOI	10.17600/1100140
Objective	The cruise aimed to answer the following questions: What environmental conditions are necessary for optimal growth of Trichodesmium and other diazotrophic cyanobacteria? In particular, the goal was to determine the origin of iron and phosphorus and their respective roles in the growth of Trichodesmium. What role does Tichodesmium play and what biogeochemical consequences does the development of these organisms have on the environment? Which phytoplankton communities develop, what kinds of food webs are built, what kinds of nitrogen, carbon and phosphorus fluxes are established before, during and after Trichodesmium blooms? Three set points were occupied: 1) Lagoon (21 deg 57,30'S; 166 deg 45'E) at Ouinne (3 days), 2) Santal Bay à Lifou (167 deg 04'E; 20 deg 51'S) at a depth of 1,050 m (3 days), 3) Loyaute Channel (21 deg 30'S; 167 deg 00'E) at a depth of 2,100 m (4 days). Comments on the cruise's progression: Excellent on-board working conditions. The trigger mechanism for closing the rosette bottles broke. David Varillon made some makeshift repairs. The system worked until the end of the cruise. The related programs are 1 ) IRD: DIAPAZON program coordinated by UR Cyano and the Lodyc, 2) INSU: national PROOF program.

Sea/Ocean

Coral Sea

Ports

Port of departure : Noumea (New Caledonia)

Port of return : Noumea (New Caledonia)

Project

JGOFS - FRANCE/PROOF

Scientific Authority

COM / LAB. D'OCEANOG. PHYS. & BIOGEOCHIMIQ. (LOPB) - LUMINY

UMR 6535

Campus de Luminy

13288 MARSEILLE CEDEX 9

+33(0)4 91 82 91 15

queguiner@com.univ-mrs.fr

Participating bodie(s)

IRD pour la partie travail de terrain ; IRD, CNRS, IUEM et Université pour les analyses et l'exploitation des donnees.

Discipline(s)

ENVIRONMENT
PHYSICAL OCEANOGRAPHY
BIOLOGICAL OCEANOGRAPHY
CHEMICAL OCEANOGRAPHY

Code	Label	Quantity	PI
B01	Primary productivity C14 and 32P methods - 10 complete profiles	-	LE BOUTEILLER Aubert
B02	Phytoplankton pigments (eg chloroph 10 chlorophyll pigment profiles with size fractionation, 6 phycoerythrin pigment profiles	13 stations	NEVEUX Jacques
B06	Dissolved organic matter (inc DOC) Sampling for MOD measurement with spectrophotometer	8 samples	DUPOUY Cécile
B07	Pelagic bacteria/micro-organisms Profiles of heterotrophic bacteria counts by flow cytometer	7 profiles	BLANCHOT Jean
B08	Phytoplankton Vertical and horizontal net lines for filament and bundle counting	20 hauls	NEVEUX Jacques
B71	Particulate organic matter (inc POC At each fixed point, particulate organic phosphate profiles	8 profiles	MOUTIN Thierry
B73	Sediment traps 24h deployment (100 and 200m) in Baie de Santal & 2*24h in Chenal des Loyautés	-	RODIER Martine
D71	Current profiler (eg ADCP) Continuous measurements (except in the lagoon) using the ADCP on board	-	VARILLON David
H09	Water bottle stations Niskin rosette (12 bottles of 8l) - Go-Flo bottles (5l) - Noex bottles (5l)	13 stations	VARILLON David
H10	CTD stations PRES, TEMP, Salinity - Fluorescence, Transmissiometry (uncontrolled)	25 stations	VARILLON David
H17	Optics (eg underwater light levels) 27 Hydroscat-6, 15 targets with Simbada 03 from LOA Lille, absorption	25 stations	DUPOUY Cécile
H22	Phosphate Dissolved phosphate profiles (on board), 3 MAGIC phosphorus profiles (deferred)	12 stations	RODIER Martine
H23	Total - P Particulate phosphate profiles + size fractionations	3 stations	VAN DEN BROECK Nathalie
H24	Nitrate Nitrate profiles (analyses at the common lab of the Noumea Centre)	11 stations	RODIER Martine
H25	Nitrite Nitrite profiles (analyses at the common lab of the Noumea Centre)	11 stations	RODIER Martine
H30	Trace elements Total and dissolved iron profiles (0 to 80 m)	6 stations	RODIER Martine
H32	Isotopes Analysis of delta-N15 + 6 samples collected in sediment traps	5 stations	LE BOUTEILLER Aubert
H71	Surface measurements underway (T,S) On-board thermosalinometer used continuously	-	LE BOUTEILLER Aubert
H76	Ammonia NH4 profiles (on-board analyses)	11 stations	LE BOUTEILLER Aubert
M02	Incident radiation Continuous measurement of incident PAR radiation with integration	-	LE BOUTEILLER Aubert

Summary of measurements

-Physical oceanography: temperature, salinity, ADCP current measurements.
-Chemistry: NO3, NO2, NH4, PO4. Total iron and dissolved iron in the euphotic layer.
-Phytoplankton pigments using a fluorimeter and a spectrofluorimeter.
-Picophyotoplankton and heterotrophic bacterial cell counts using flow cytometer.
-Samples taken for molecular biology and delta-N15 analyses.
-Sedimentation measurements using particle traps (3 deployments).
-Primary production in the water column (10 days of measurements).
-Phosphate assimilation and phosphorus cycle.
-Samples taken with a 35 micron net.
-Measurements using the Simbada-3 and Hydroscat-6, measuring absorption and the dissolved fraction.

Location map

Joint document(s)

Data managed by SISMER

Bibliography

Publications

Dupouy Cécile, Whiteside Andra, Tan Jing, Wattelez Guillaume, Murakami Hiroshi, Andréoli Rémi, Lefèvre Jérôme, Röttgers Rüdiger, Singh Awnesh, Frouin Robert (2023). A Review of Ocean Color Algorithms to Detect Trichodesmium Oceanic Blooms and Quantify Chlorophyll Concentration in Shallow Coral Lagoons of South Pacific Archipelagos. Remote Sensing, 15(21), 5194 (25p.). Publisher's official version : https://doi.org/10.3390/rs15215194 , Open Access version : https://archimer.ifremer.fr/doc/00871/98267/

Dutheil Cyril, Aumont Olivier, Gorgues Thomas, Lorrain Anne, Bonnet Sophie, Rodier Martine, Dupouy Cecile, Shiozaki Takuhei, Menkes Christophe (2018). Modelling N2 fixation related to Trichodesmium sp.: driving processes and impacts on primary production in the tropical Pacific Ocean. Biogeosciences, 15(14), 4333-4352. Publisher's official version : https://doi.org/10.5194/bg-15-4333-2018 , Open Access version : https://archimer.ifremer.fr/doc/00419/53042/

Moutin Thierry, Wagener Thibaut, Caffin Mathieu, Fumenia Alain, Gimenez Audrey, Baklouti Melika, Bouruet-Aubertot Pascale, Pujo-Pay Mireille, Leblanc Karine, Lefevre Dominique, Nunige Sandra Helias, Leblond Nathalie, Grosso Olivier, de Verneil Alain (2018). Nutrient availability and the ultimate control of the biological carbon pump in the Western Tropical South Pacific Ocean. Biogeosciences, 15(9), 2961-2989. Publisher's official version : https://doi.org/10.5194/bg-15-2961-2018 , Open Access version : https://archimer.ifremer.fr/doc/00420/53113/

Barboza Tenorio Marcio Murilo, Dupouy Cecile, Rodier Martine, Neveux Jacques (2018). Trichodesmium and other planktonic cyanobacteria in New Caledonian waters (SW tropical Pacific) during an El Niño episode. Aquatic Microbial Ecology, 81(3), 219-241. Publisher's official version : https://doi.org/10.3354/ame01873 , Open Access version : https://archimer.ifremer.fr/doc/00439/55078/

Cravatte Sophie, Kestenare Elodie, Eldin Gerard, Ganachaud Alexandre, Lefevre Jerome, Marin Frederic, Menkes Christophe, Aucan Jerome (2015). Regional circulation around New Caledonia from two decades of observations. Journal Of Marine Systems, 148, 249-271. https://doi.org/10.1016/j.jmarsys.2015.03.004

Fuchs Rosalie, Pinazo Christel, Douillet R., Fraysse Marion, Grenz Christian, Mangin A., Dupouy C. (2013). Modelling ocean-lagoon interaction during upwelling processes in the South West of New Caledonia. Estuarine Coastal And Shelf Science, 135, 5-17. https://doi.org/10.1016/j.ecss.2013.03.009

Fuchs R., Dupouy C., Douillet Pascal, Caillaud Matthieu, Mangin A., Pinazo Christel (2012). Modelling the impact of a La Nina event on a South West Pacific Lagoon. Marine Pollution Bulletin, 64(8), 1596-1613. https://doi.org/10.1016/j.marpolbul.2012.05.016

Dupouy Cecile, Neveux Jacques, Ouillon Sylvain, Frouin Robert, Murakami Hiroshi, Hochard Sebastien, Dirberg Guillaume (2010). Inherent optical properties and satellite retrieval of chlorophyll concentration in the lagoon and open ocean waters of New Caledonia. Marine Pollution Bulletin, 61(7-12), 503-518. https://doi.org/10.1016/j.marpolbul.2010.06.039