MOANA-MATY 2018

Name: MOANA-MATY 2018
Start: 2018-09-19
End: 2018-10-16
Location: Pacific Ocean

Type	Oceanographic cruise
Ship	Alis
Ship owner	IRD
Dates	19/09/2018 - 16/10/2018
Chief scientist(s)	RODIER Martine
	IRD CENTRE DE PAPEETE Chemin de l'ahari PK 3800 - Arue BP 529 98713 PAPEETE (POLYNESIE FRANCAISE) (689) 43 98 87 https://polynesie.ird.fr/
DOI	10.17600/18000580
Objective	Island Mass Effect around the Marquesas Islands The Marquesas Islands are characterized by the presence throughout the year of a remarkable biological enrichment which is attributed to the Island Mass Effect (IME). This enhancement of productivity and biomass can extend up to 800km downstream of the islands and is mainly noticeable west of the archipelago and more marked in austral summer. While these enrichments are particularly visible by satellite, there is very little in situ data to conclude on 1) the biophysical processes involved, i.e. hydrodynamic conditions associated with the presence of the archipelago (coastal upwelling, eddies formation), terrigenous inputs controlled by wind and rain regimes, non-limiting micro-nutrients, influence of equatorial upwelling, and 2) the structure and functioning of the planktonic ecosystem. The objective of the MOANA-MATY cruises is to understand through in situ measurements the physical and biogeochemical processes at the origin of the IME in the Marquesas archipelago as well as the nature of enrichment and its impact on the higher trophic levels. In this study area, the different hypotheses put forward on the origin and nature of enrichments can only be confirmed by a detailed study of i) hydrodynamics and hydrology, ii) biogeochemistry and iii) structure and dynamics of phyto- and zooplankton communities. Two cruises have been scheduled at different seasons: MOANA-MATY 1 (Sept-Oct 2018) is the first cruise in the cool season, the second cruise will be held in austral summer (Feb.-March 2019). The sampling strategy takes into account both the north-south and onshore-offshore gradients, as well as the contrasted enriched and turbulent zone in the wake of the islands vs. the upstream non-enriched zone.

Sea/Ocean

Pacific Ocean

(Marquesas archipelago)

Ports

Port of departure : Papeete (French Polynesia)

Port of return : Papeete (French Polynesia)

Limits

North	South	West	East
-7.7	-10.2	-141.0	-138.7

Scientific Authority

IRD CENTRE DE PAPEETE

Chemin de l'ahari PK 3800 - Arue

BP 529

98713 PAPEETE (POLYNESIE FRANCAISE)

(689) 43 98 87

https://polynesie.ird.fr/

Participating bodie(s)

IRD, CNRS, Moss Landing Marine Laboratories (USA)

Discipline(s)

CHEMICAL OCEANOGRAPHY
BIOLOGICAL OCEANOGRAPHY
ENVIRONMENT
PHYSICAL OCEANOGRAPHY

Code	Label	Quantity	PI
B01	Primary productivity Double isotopic marking 13C/ 15N (112 C/NO3, 112 C/NH4, 112 C/N2)	336 samples	RAIMBAULT Patrick
B02	Phytoplankton pigments (eg chloroph Fluorimetry - 390 (total), 166 (fractionnée 2 et 10µm)	390 samples	RODIER Martine
B02	Phytoplankton pigments (eg chloroph HLPC	338 samples	UITZ Julia
B06	Dissolved organic matter (inc DOC) Colorimetry	100 samples	RAIMBAULT Patrick
B07	Pelagic bacteria/micro-organisms Flow cytometry	258 samples	RODIER Martine
B08	Phytoplankton Optical microscopy	52 observations	BEKER Beatriz
B09	Zooplankton Zooscan, microscopy	-	RODIER Martine
B71	Particulate organic matter (inc POC Mass spectrometry	336 samples	RAIMBAULT Patrick
D05	Surface drifters/drifting buoys SVP	15 deployments	MAES Christophe
D06	Neutrally buoyant floats Argos (4) and Bio-argos (2)	6 deployments	MARTINEZ Elodie
D71	Current profiler (eg ADCP) Continuous shipboard ADCP	-	MARTINEZ Elodie
G73	Single-beam echosounding EK60 continuous	-	LEBOURGES-DHAUSSY Anne
H09	Water bottle stations Rosette Niskin 12 x 8L	50 stations	BACHELIER Céline
H10	CTD stations SBE 19 (TS, O2, transmissiometer, fluorometer)	58 stations	BACHELIER Céline
H16	Transparency (eg transmissometer) Transmissiometer	58 stations	BACHELIER Céline
H17	Optics (eg underwater light levels) TRIOS	58 stations	DUPOUY Cécile
H21	Oxygen	58 stations	BACHELIER Céline
H22	Phosphate Colorimetry	468 samples	RODIER Martine
H24	Nitrate Colorimetry	468 samples	RODIER Martine
H25	Nitrite Colorimétrie	468 samples	RODIER Martine
H26	Silicate Colorimetry	468 samples	RODIER Martine
H30	Trace elements Iron, Zinc, organic ligants - 70 (dissolved), 70 (total) 21 Cu/Organic speciation, 38 humic, 26 particulate	-	GRAND Maxime
H71	Surface measurements underway (T,S) TSG of the Alis continuously	-	BACHELIER Céline
H76	Ammonia Fluorimetry	520 samples	RODIER Martine
M02	Incident radiation SPAR Biospherical continuous	-	BACHELIER Céline
P05	Other dissolved substances Spectrophotometry, 200 cm LWCC	8 samples	DUPOUY Cécile

Positionning system

Geodetic system : WORLD GEODETIC SYSTEM 1984 = WGS84

Positioning system : GPS naturel

Scientific context

Context: The Marquesas archipelago (218°-222°E/8°-11°S) lies to the north-east of French Polynesia and covers an area of 100,000 km². Located in a tropical or near-equatorial zone, the archipelago is under the influence of the South Equatorial Current (SEC). This surface current, forced by the trade winds, flows west/southwest and conditions the oceanic environment of French Polynesia (Rougerie & Ranger, 1994). The Marquesas Islands, ranging in size from 10 to 40 km wide, represent the first series of obstacles that will disrupt the flow of SEC waters. These disturbances can lead to coastal upwelling and eddies in the wake of the islands, resulting in upwelling of nutrients. The presence of islands also disrupts atmospheric flows and modulates local meteorology. From a biogeochemical point of view, the Marquesas form the southern boundary between the mesotrophic waters of the equatorial upwelling (chlorophyll-a concentration - Chla > 0.2 mg.m^-3) and the oligotrophic waters (Chla <0.1 mg.m^-3) characteristic of the French Polynesian ocean waters. Finally, the Marquesas Islands (central South Pacific) are characterized by a strong phytoplanktonic enhancement (island mass effect, IME), and rich marine biodiversity. This strong phytoplanktonic enhancement (IME) is visible by satellite (Fig. 1) and observed throughout the year, although more markedly in the austral summer and in the western part of the archipelago. The chlorophyll plume is extensive considering the size of the islands, reaching up to 800km during the La Niña period (Signorini et al 1999). However, the pelagic oceanic environment of this archipelago has been poorly studied and mechanisms at the origin of this IME remain unknown

Fig. 1. Chla averaged over 2001-2007, from the SeaWiFS radiometer (the purple line delimits the EEZ of French Polynesia)

Although remarkable for its biological richness and diversity, the pelagic ocean environment of the Marquesas archipelago has been little studied and data remains patchy (BIOSOPE 2004, Claustre et al. 2008; TARA expedition 2011, oceans.taraexpedition.org; Pakaihi I te Moana 2012, Martinez et al., 2016, 2020). Many questions thus remain unanswered, such as those concerning the physical mechanisms underlying IME as well as the composition of planktonic assemblages and their impact on higher trophic levels (Gove et al., 2015). Understanding this IME in the Marquesas is important because it represents a "hotspot of phytoplankton biomass" in a largely oligotrophic tropical ocean and is essential for higher trophic levels and, in terms of fisheries resources, for French Polynesia. In this context, the multidisciplinary MOANA-MATY project (2014-2017) was launched, combining different approaches such as field and satellite observations (Martinez et al., 2018) and coupled physical biogeochemical modeling (Raapoto et al., 2018; 2019). The MOANA-MATY campaigns represent the in situ part of this project which was supported and co-funded by CNRS-INSU (LEFE/CYBER and GMMC) and by the French Polynesia Research Delegation for the campaign part.

Objectives / scientific questions: The main objectives of the project are 1) to understand the physical and biogeochemical processes at the origin of the Marquesas IME, 2) to characterize the seasonal and inter-annual variability of phytoplankton and the physical and biogeochemical processes involved. In order to take seasonal variability into account and to coincide with contrasted situations in terms of hydrodynamics and phytoplankton biomass richness, two campaigns were scheduled: MOANA-MATY 1 (presented here), which took place in Sept-Oct 2018 in the cool season aboard the N/O Alis (and MOANA-MATY 2 in Feb-March 2019 in the warm season). The MOANA-MATY 1 cruise plan includes 37 stations (24 short + 13 long "biogeochemistry + iron", Fig. 2) sampled around the Marquesas and continuous data along the Papeete-Marquise transit. The sampling plan is based on results from the 2012 "Pakaihi I te Moana" cruise, hydrodynamic model outputs and satellite data. It takes into account 1) the coast-ocean gradient , 2) the north-south differences in both the physical environment and the biomass and structure of the planktonic communities, and 3) the contrast between the enriched zone in the wake of the islands and the unenriched zone upstream.

Fig. 2. MOANA-MATY 1 cruise : ship route and position of sampling stations. Long stations in yellow, short stations in red.

Main results

Hydrodynamics and particle drift: drifting buoys SVPs versus GEKCO product (Cassianides et al., 2020; research training of Cassianides A., 2019; Le Roux C., 2020; Castant J., 2020)

15 surface drifting buoys (SVPs) were deployed during MOANA-MATY 1 (Fig. 3), which, in addition to providing the meteorological authorities with atmospheric observations, made it possible to assess the relevance of the GEKCO (Geostrophic and Ekman Current Observatory) surface current product derived from satellite observations. These current fields are the sum of the geostrophic component (derived from sea surface height elevation) and the Ekman component (derived from wind stress).

Fig. 3 Trajectories of surface drifters 15 days after the campaign

Lagrangian simulations were carried out, releasing particles into the GECKO current fields north of the archipelago where the SVPs were deployed every day from October 1 to 10, 2018 (Fig. 4). Their trajectories were calculated for 3 months and then compared with those of the SVPs deployed during the mission. The dispersion of the simulated particles is more consistent with that of the SVPs when the wind component is divided by 2, indicating an overestimation of the Ekman component in GEKCO and suggesting the use of a 50% corrected product of this component.

Fig. 4: Comparison of the dispersion of surface drifters deployed during MOANA-MATY 1 (blue crosses) with that of fictitious particles (green circles).

In addition to data from drifting buoys, measurements from the S-ADCP attached to the NO Alis were used to map currents during each cruise (Fig. 5).

Fig. 5: Average currents in the 19-195m layer recorded during the MOANA-MATY1 cruise.

Iron distribution (Grand M., workshop dec. 2022)

Iron bioavailability is a limiting factor in phytoplankton production in many oceanic regions, and one of the aims of the MOANA-MATY 1 campaign was to measure this bioavailability in the Marquesas zone and test the hypothesis of iron limitation in this "High nutrient" region ((NOx + NH₄ = 4.21 ± 1.3 µmol L^-1; PO₄ = 0.48 ± 0.07 µmol L^-1; Si(OH)₄ = 2.0 ± 0.3 µmol L^-1; mean values during the campaign). We therefore sampled 13 stations for Fe, targeting five distinct depths within the upper 90 meter using a Teflon bellows pump and a 100 m acid-cleaned hose. To further our understanding of freshwater Fe contributions, we also collected surface samples from Waituha Bay (Eiao) and stream samples from Eiao and Ua Pou. The samples were then analyzed for dissolved Fe (dFe: filtered samples) and total dissolvable Fe (TDFe: unfiltered samples) at the Moss Landing Marine Laboratories using a luminol chemiluminescence Flow Injection Analysis system, modified from Obata et al. (1993). The method showcased a limit of detection at 0.02 nM, with an analytical precision of < 5% for [dFe] > 0.15 nM and 5-15% for lower concentrations. Analytical accuracy was validated through the analysis of SAFe and GEOTRACES reference samples, achieving recoveries exceeding 95% for both D1 (n=18) and GSC (n=4).

The mean surface dFe during MOANA-MATY 1 was 0.12 ± 0.05 nM, in agreement with prior studies such as Blain et al. (2008). While much of the study area exhibited consistent low surface dFe concentrations (approximately 0.15 nM), two specific stations, located northwest of Nuku Hiva (orange triangle) and on the western side of Ua Pou (green cross), displayed elevated concentrations up to 0.25 nM (Fig. 6). These elevated concentrations persisted throughout the upper 90 meters at these stations.

Fig. 6. Dissolved Fe during MOANA-MATY 1. Bottom left: mean surface dFe, Bottom right: vertical dFe profiles

The TDFe data, encompassing both dFe and labile Fe linked with biogenic and lithogenic particles, highlighted increased values on the western peripheries of all islands (Fig. 7). This suggests a potential, albeit localized, Fe contribution from the islands' sediments. Stream water samples from Eaio and Ua Pou showed Fe concentrations of 82 nM and 280 nM, respectively. The variance in concentrations might be attributed to differing lithologies. In collaboration with Helene Planquette (LEMAR), these insights will be integrated with the particulate trace metal data to elucidate the potential influence of island sediments in supplying bioavailable Fe.

Fig. 7. Total Dissolvable Fe (TDFe) during MOANA-MATY 1. Bottom left: mean surface TDFe, Bottom right: vertical TDFe profiles.

Hydrodynamic activity and phytoplankton distribution: in situ and satellite data (Cassianides et al., 2020; Hermilly T.'s thesis 2022-2025; research training of Charavit J. 2019; Matitia, 2019)

Two remarkable phytoplankton blooms were observed from GlobColor-GSM satellite images during and just after the campaign, and were studied by combining satellite observations and in-situ data from the MOANA-MATY 1 campaign. For example (Fig. 8), surface current observations combined with a Lagrangian approach illustrate that the particles observed at the level of the chlorophyll plume (Chla) on October 3, 2018 in the south of the archipelago passed in direct proximity to the islands (95% of cases), indicating that the islands are at the very origin of the biological enrichments observed. Mesoscale circulation then modifies the distribution of the Chla plume over several hundred kilometers downstream of the islands.

Fig. 8. Left: Chla distribution (µg L^-1) derived from GlobColor-GSM ocean color images on Oct. 3, 2018. Right: Chl and particle drift trajectories (black line) derived from backward Lagrangian analysis from their initial positions (magenta dots). The three arrows indicate the preferential paths taken by the particles, around Ua Huka, Nuku Hiva and Ua Pou (red), Hiva Oa (green), Fatu Hiva (blue).

In agreement with satellite data, in situ Chla distribution (Fig. 9) showed that the highest enrichments occurred near the islands in the surface layer (0.80 to 0.90 mg Chla L^-1) and mostly downwind of the islands, indicating favorable environmental conditions for phytoplankton development (macro- and micronutrient inputs, stability of the water column, etc ...). However, due to the strong mesoscale dynamic activity observed in austral winter, which can modulate the plumes (Fig. 8), the contrast between Chla values upwind and downwind of the islands was not very pronounced. Outside the rich zones, Chla was distributed deeper with a maximum (DCM) between 60-100m.

Fig. 9. Chla distribution and primary production in austral winter during the MOANA-MATY 1 cruise. A) Total Chla by HPLC, B) Chla integrated 0-15m C) Primary production. D) Surface Chla derived from GlobColor satellite images. The white line indicates the area windward of the islands (left) and leeward of the islands (right).

Integrated Chla values on the euphotic layer (0.1% light) ranged from 10.4 to 52.2 mg Chla m^-2 (30.8 ± 9.2 mg Chla m^-2). These biomass values are associated with high primary production values ranging from 144 to 682 mgC m^-2 d^-1 (320 ± 184 mgC m^-2d^-1) with maximum values at the surface (0-20/30m) and near Ua Pou (Fig. 9). These biomass and production values reflect a mesotrophic (HNLC-type) system when compared with equatorial upwelling data between 140°W and 110°W of the order of 26.5 ± 3.5 mg Chla m^-2and 748 ± 110 mg C m^-2d^-1, respectively (Balch et al., 2011). The pelagic ecosystem around the Marquesas archipelago thus appears to be a globally productive system, but subject to strong variability on a smaller scale of time and space, linked in large part to strong and complex oceanic dynamic activity.

Chlorophyll biomass was largely dominated by picoplankton (Chla < 2µm representing 75 to 95% of total Chla ) as in the equatorial upwelling (Blach et al., 2011), and in agreement with previous observations in the same area (Martinez et al. 2012). Pigment data (HPLC) also showed a predominance of picocyanobacteria (40-60% of total Chla), largely dominated by Synechococcus near surface islands with abundances that can exceed 80 ×10³ cells mL^-1, while Prochloroccoccus dominate elsewhere (flow cytometry data). Observations using inverted microscopy have also enabled us to draw up an initial taxonomic inventory of nano- and microphytoplankton, as well as highlighting changes in communities within the archipelago, coupled with high variability in abundance (Fig. 10). Flagellates dominated with two main groups: Prymnesiophytes (16 species, mainly Coccolithophores) and Dinoflagellates (81 species). Diatoms (65 species) are most abundant downstream of the islands, with a maximum near Ua Pou. These microscopy, pigment and flow cytometry data will be supplemented/confirmed by meta-barcoding DNA measurements during the second MOANA-MATY 2 mission.

Fig. 10. Nano and microphytoplankton community composition in austral winter during MOANA-MATY 1 (inverted microscope observations). X-axis = #station-depth (in m). Ua Huka (UK) , Hiva Oa (HO), Ua Pou (UP), Nukku Hiva (NK), Eiao (EO).

The phytoplankton data set raises the questions of 1) how much of the Chla (and nutrients) observed in the plumes is directly advected from the islands, and how much is potentially induced by the dynamics of eddies or front zones; and 2) how the structure of phytoplankton communities will structure the overall food web. Large-scale satellite studies, modelling and the monitoring of physical-biogeochemical floats (T. Hermilly's thesis, 2022-2025) combined with the study of macro- and micronutrients and phyto- and zooplankton communities (stocks and C, N fluxes), will be essential to understand the origin of enrichments and go further in the study of the functioning of the pelagic ecosystem around the Marquesas.

Acoustic measurements and distribution of micronekton (Barbin et al., 2020; research training of Barbin L., 2020)

Acoustic densities acquired by recording at 38kHz allow us to study the abundance and distribution of micronekton. These data showed a strong latitudinal gradient between Tahiti and the Marquesas, with high values in the HNLC zone near the Marquesas Islands and minima in the oligotrophic zone during transits to and from Tahiti (Fig. 11). The vertical migrations of micronektonic organisms were visible in all the data, with the presence of two deep scattering layers (DSL) between 0-200m and 400-600m.

Fig. 11: Acoustic intensity per unit volume (volume backscattering coefficient, Sv in dB) at 38 kHz as a function of time during MOANA-MATY 1. The dotted lines delimit the Marquesas archipelago zone.

In the Marquesas, acoustic data per unit area (NASC, nautical area scattering coefficient; Fig. 12) were evenly distributed around the archipelago day and night, showing no significant differences between upwind ("upstream") and downwind ("downstream") areas,

Fig. 12. 38kHz vertical profiles of average NASC in the archipelago, following an "upstream/downstream" plane of the islands (N/E vs. S/W). Night (blue) and day (red) profiles.

The most important environmental variables in the vertical structuring of micronekton in the South Pacific are the amount of dissolved oxygen and the depth of the euphotic zone (Receveur et al., 2019). A comparison between SINC and environmental parameters at the archipelago scale suggested that oxygen was the hydrological parameter that most impacts the vertical distribution of micronekton. Conversely, ocean dynamics in the archipelago appeared to play a minor role. However, the results underlined the complexity of micronekton distribution around the islands, and the difficulty of establishing direct links between its distribution and environmental parameters.

List of L3, M1 and engineer research training using MOANA-MATY 1 data (M2 and thesis see the section "References")

Charavit Joséphine (2019) Distribution spatiale de la Chlorophylle a et structure de taille du phytoplancton dans l'archipel des Marquises à deux saisons contrastées (campagnes océanographiques Moana-Maty 1 et 2. M1 Biologie Ecologie et Evolution, Aix-Marseille Université (encadrante M. Rodier - EIO)

Matitia Tanya (2019). Effet d'iles aux Marquises : étude de la variabilité spatiale et saisonnière des paramètres physiques et biogéochimiques dans l'archipel. 3rd yr of Bachelor, Université Montréal, Canada (encadrantes M. Rodier - EIO & E. Martinez - LOPS)

Castant Jerome (2020). Evaluation de la variabilité des masses d'eau dans l'archipel à partir des données des flotteurs Argo durant la période 2018-2019. M1 Université du littoral (encadrants C. Maes & E. Martinez - LOPS)

Le Roux Claire (2020). Current climatology derived from Lagrangian drifters in the region of The Marquesas Islands. Ecole d'ingénieur Ecole centrale Lyon (encadrants C.Maes & G. Charria - LOPS)

Cited references

Balch, W. M., Poulton, A. J., Drapeau, D. T., Bowler, B. C., Windecker, L. A., & Booth, E. S. (2011). Zonal and meridional patterns of phytoplankton biomass and carbon fixation in the Equatorial Pacific Ocean, between 110 W and 140 W. Deep Sea Research Part II: Topical Studies in Oceanography, 58(3-4), 400-416

Blain, S.; Bonnet, S.; Guieu, C. (2008) Dissolved iron distribution in the tropical and sub tropical South Eastern Pacific. Biogeosciences, 5, 269¿280.

Blanke, B.; Raynaud, S. (1997) Kinematics of the Pacific Equatorial Undercurrent: An Eulerian and Lagrangian Approach from GCM Results. Journal of Physical Oceanography, 27(6), 1038-1053.

Claustre, H.; Sciandra, A.; Vaulot, D. (2008) Introduction to the special section bio-optical and biogeochemical conditions in the South East Pacific in late 2004: The BIOSOPE program. Biogeosciences, 5, 679¿691.

Martinez E., Rodier M., Maamaatuaiahutapu K. (2016) Environnement océanique des Marquises. In Galzin R., Duron S.-D. & Meyer J.-Y. (eds), Biodiversité terrestre et marine des îles Marquises, Polynésie française. Société Française d'Ichtyologie, Paris : 123-136.

Martinez, E., Raapoto, H., Maes, C., Maamaatuaihutapu, K. (2018) Influence of Tropical Instability Waves on Phytoplankton Biomass near the Marquesas Islands. Remote Sensing, 10(4), 640.

Martinez E., Rodier M., Pagano, M., Sauzède R. (2020) Plankton spatial variability within the Marquesas archipelago, South Pacific. Journal of Marine Systems, 212, 103432

Obata, H., Karatani, H., Nakayama, E. (1993). Automated determination of iron in seawater by chelating resin concentration and chemiluminescence detection. Analytical Chemistry, 65(11), 1524-1528.

Receveur, A. (2019). Ecologie spatiale du micronecton: distribution, diversité et importance dans la structuration de l'écosystème pélagique du Pacifique sud-ouest (Doctoral dissertation, Aix-Marseille).

Data acquired and analyses carried out at sea and on shore

At sea

Short stations (2-3h)

CTD/rosette/Niskin 8L to 1000m depth (vertical profiles of temperature, salinity, fluorescence, oxygen, turbidity) and sampling at 12 depths for photosynthetic pigments-HPLC, total and fractionated Chl-a, microorganisms by flow cytometry
Vertical zooplankton haul (60µm mesh) 0-500m: integrated zooplankton biomass and taxonomy
LISSTx100 down to 220m : volume and particle size spectrum 2.5-300µm
Trios in surface (15 minutes) between 11am and 2pm: radiometric reflectance measurements

Long stations (6-7h)

CTD/rosette down to 1000m depth and sampling at 12 depths (same parameters as at short stations + CDOM + sampling for phytoplankton abundance and taxonomy)
Vertical zooplankton haul (60µm mesh) 0-500m
LISSTx100 down to 300m
CTD/rosette to 300m with sampling at 12 depths (pigments, primary production/N-assimilation, nutrients, dissolved organic matter)
Simulated in situ incubation (24h) on deck (incubateur with light screens) for primary production, NO₃ and NH₄ assimilation and N₂ fixation
Trios in surface (15 minutes): reflectance measurements
Sampling with Teflon pump and tubing at 8 depths between 10 and 90m for dissolved and particulate iron, ligants, humic matter, trace metals

Continuous measurements and XBT

XBT (t0 and 800m maximum) carried out en route on transits between stations and on the Nuku-Hiva - Tahiti return transit.
Continuous measurements of surface temperature and salinity using the R/V Alis thermosalinograph.
Current measurements down to 500-600m using the R/V Alis S-ADCP (Acoustic Doppler Current Profiler). The ADCP signal can also be analyzed as a signature of zooplankton and micronekton biomass.
Acoustic measurements using multi-frequency EK60 echo sounder (38, 70, 120 and 200 kHz) down to 600m (micronekton signature).

Floats launched during the campaign

2 physical-biogeochemical (BGC)-ARGO PROVOR floats (NKE-instrumentation) and 4 physical ARGO floats
15 Surface Velocity Program (SVP) floats from Météo France and NOAA-USA

Summary of parameters, methods and number of samples collected during the MOANA-MATY 1 cruise (100% on the initial objectives)

Published data

Barbin Laure, Habasque Jeremie, Martinez Elodie, Rodier Martine (2020). Acoustic data from MOANA MATY surveys. https://doi.org/10.17882/75317

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/

Cassianides Angelina, Martinez Elodie, Maes Christophe, Carton Xavier, Gorgues Thomas (2020). Monitoring the Influence of the Mesoscale Ocean Dynamics on Phytoplanktonic Plumes around the Marquesas Islands Using Multi-Satellite Missions. Remote Sensing, 12(16), 2520 (10p.). Publisher's official version : https://doi.org/10.3390/rs12162520 , Open Access version : https://archimer.ifremer.fr/doc/00649/76115/

References of Technical Reports

Barbin L., Habasque J., Martinez E., Rodier M. (2020). Acoustic data from MOANA MATY surveys. SEANOE. doi.org/10.17882/75317

References of International Seminar Communications

Hermilly T., Martinez E., Uitz J., Schmechtig C. Biogeochemical dynamics of contrasted regions of the South Pacific Ocean: a study based on BioGeoChemical-Argo floats. Trevor Platt Science Foundation symposium, Plymouth Marine Laboratory, 10-12 août 2023 (poster)

Martinez E., Rodier M., Maes C., Cassianides A. The Masquesas Island Mass Effect: impact of coastal to large-scale dynamics Ocean Sciences Meeting (OSM) 2022. February 27 - March 4 2022 / Honolulu, HI, USA. (poster, PS 05)

References of National Seminar Communications

Hermilly T., Martinez E., Uitz J., Schmechtig C. Biogeochemical dynamics of contrasted regions of the South Pacific Ocean: a study based on BioGeoChemical-Argo floats. Science en Theizh, Les Capucins, Brest, 15 avril 2023 (poster)

Hermilly T., Martinez E., Uitz J. Biogeochemical dynamics of contrasted regions of the South Pacific Ocean: a study based on BioGeoChemical-Argo floats. Journées LEFE-GMM, Ifremer Plouzané, 31 mai-2 juin 2023 (poster)

Martinez E., Rodier M., Poteau A., Claustre H., Uitz J., Hermilly T., Renard S., Maes C., Maamaatuaiahutapu K. Etude de la dynamique phytoplanctonique dans le Pacifique Sud : une variété de problématique au sein d'un même bassin océanique. Journées LEFE - GMMC, Ifremer Plouzané, 31 mai-2 juin 2023 (oral)

Martinez E. Projet MOANA-MATY. Journées LEFE - GMMC, Session 4 "Argo", 26 novembre 2021 (oral)

References of Contracts reports (European Union, FAO, Convention, Collectivities...)

M. Rodier, E. Martinez (2019) Moana o te Ati Enana 2017-2019 "Biodiversité planctonique aux îles Marquises". Rapport final - Convention N° 07498 Délégation à la Recherche de la Polynésie française , 19 pages.

DEA or MASTER 2 using campaign data

Laure Barbin (2020) Etude de la distribution du micronecton autour des îles Marquies en lien avec l'environnement abiotic, à partir des données acoustiques acquises lors des campagnes Moana Maty. M2, Université Paul Sabatier, Toulouse (encadrants J. Habasque - LEMAR & E. Martinez - LOPS)

Angélina Cassianides (2019) Impact de l'activité à mésoéchelle sur la distribution du phytoplankton lors de deux "blooms" dans l'archipel des Marquises. M2 Sciences de la mer OPB, Aix Marseille Université, Marseille (encadrants E. Martinez & C. Maes - LOPS)

File	Processing level	Size	Format
Restricted access RAW	RAW DATA	85 GB	KONGSBERG .RAW
Restricted access DONNEES	RAW DATA	183 MB	KONGSBERG .ALL
Restricted access HAC	RAW DATA	94 GB	HYDRO ACOUSTI .HAC