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1. Developing erosion models for integrated coastal zone management: A case study of The New Caledonia west coast

Author

Morgan Mangeas, Julia Printemps, Pascal Dumas, Gaelle Luneau, Université de la Nouvelle-Calédonie (UNC), Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie]), UMR 228 Espace-Dev, Espace pour le développement, Université de Guyane (UG)-Université des Antilles (UA)-Institut de Recherche pour le Développement (IRD)-Université de Perpignan Via Domitia (UPVD)-Avignon Université (AU)-Université de La Réunion (UR)-Université de Montpellier (UM), Unité de pathologie animale, Institut National de la Recherche Agronomique (INRA), Institut de Recherche pour le Développement (IRD)-Université de Perpignan Via Domitia (UPVD)-Avignon Université (AU)-Université de La Réunion (UR)-Université de Montpellier (UM)-Université de Guyane (UG)-Université des Antilles (UA), Grenz, Christian (ed.), and Le Borgne, Robert (ed.)

Subjects
Conservation of Natural Resources, Geologic Sediments, Geographic information system, EROSION, ZONE TROPICALE, 010504 meteorology & atmospheric sciences, SYSTEME D'INFORMATION GEOGRAPHIQUE, Rain, Fringing reef, Drainage basin, 010501 environmental sciences, Aquatic Science, Oceanography, 01 natural sciences, Soil, New Caledonia, LAGON, Tropical climate, 14. Life underwater, Integrated coastal zone management, 0105 earth and related environmental sciences, Hydrology, geography, geography.geographical_feature_category, business.industry, ZONE COTIERE, Sediment, Models, Theoretical, 15. Life on land, MODELISATION, Pollution, 6. Clean water, Universal Soil Loss Equation, 13. Climate action, [SDE]Environmental Sciences, Erosion, Environmental science, business, GESTION INTEGREE
Abstract

International audience; The tropical climate and human pressures (mining industry, forest fires) cause significant sediment inputs into the New Caledonia lagoon and are a major cause of degradation of the fringing reefs. The erosion process is spatially characterized on the west coast of New Caledonia to assess potential sediment inputs in the marine area. This paper describes the methodologies that are used to map soil sensitivity to erosion using remote sensing and a geographic information system tool. A cognitive approach, multi-criteria evaluation model and Universal Soil Loss Equation are implemented. This article compares the relevance of each model in order to spatialize and quantify potential erosion at catchment basin scale. These types of studies provide valuable results for focusing on areas subject to erosion and serve as a decision-making tool for the minimization of lagoon vulnerability to the natural and human dynamics on the level of the catchment basins.

Published
2010

2. New Caledonia tropical lagoons : an overview of multidisciplinary investigations

Author

Robert Le Borgne, Martine Rodier, Grenz, Christian (ed.), and Le Borgne, Robert (ed.)

Subjects
Nitrogen, STRUCTURE DU PEUPLEMENT, PRODUCTION PRIMAIRE, Population Dynamics, Population, Environment, Aquatic Science, Cyanobacteria, Oceanography, Trichodesmium erythraeum, ABONDANCE, Water column, New Caledonia, LAGON, Aquatic plant, Phytoplankton, ETUDE COMPARATIVE, Seawater, education, Ecosystem, REPARTITION VERTICALE, education.field_of_study, biology, Ecology, FIXATION BIOLOGIQUE DE L'AZOTE, Temperature, MICROORGANISME, Plankton, biology.organism_classification, Pollution, Carbon, CYANOBACTERIE, Trichodesmium, Water Microbiology, Bloom
Abstract

While Trichodesmium erythraeum is prevalent in the semi-closed SW lagoon of New Caledonia, T. thiebautii is dominant in the more open SE lagoon. This led to the comparison of the two species from the results of two high-frequency surveys focused on T. erythraeum (Rodier and Le Borgne, 2008) and T. thiebautii (the present paper). (1) Environmental conditions and triggers of the blooms are the same: calm weather and/or temperature >26 degrees C, and temporary nutrient inputs are required for both; (2) growth rates under favorable conditions are similar (0.14-0.27 d(-1)) but (3) T. thiebautii has lower net ascent rates along the water column during blooming events, due to distinct buoyancy capacities and the resulting vertical distributions; (4) carbon and dinitrogen fixation rates are not significantly different and contribution of Trichodesmium spp. represent less than 35% and 5% of the total phytoplankton carbon and nitrogen requirements, respectively. It is concluded the two species can be mixed in ecological studies, except for their vertical distributions during the bloom periods.

Published
2010

3. New Caledonia tropical lagoons : an overview of multidisciplinary investigations

Author

Ken Ridgway, Gérard Eldin, Cécile Dupouy, Martine Rodier, Andres Vega, Christophe Maes, Alexandre Ganachaud, Patrick Marchesiello, Robert Le Borgne, Océan du Large et Variabilité Climatique (OLVAC), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD), Caractérisation et modélisation des échanges dans des lagons soumis aux influences terrigènes et anthropiques (CAMELIA), Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie])-Institut de Recherche pour le Développement (IRD [Guyane]), Echanges Côte-Large (ECOLA), Centre for Australian Weather and Climate Research, CSIRO Wealth from Oceans National Research Flagship, Grenz, Christian (ed.), and Le Borgne, Robert (ed.)

Subjects
0106 biological sciences, 010504 meteorology & atmospheric sciences, VENT, UPWELLING, Aquatic Science, Oceanography, 01 natural sciences, Water column, New Caledonia, Water Movements, Computer Simulation, Seawater, 14. Life underwater, Argo, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, TEMPERATURE DE SURFACE, Upwelling, DONNEES SATELLITE, PRODUCTION BIOLOGIQUE, 010604 marine biology & hydrobiology, Biodiversity, Plankton, Models, Theoretical, Mooring, Satellite Communications, Pollution, Current (stream), CIRCULATION OCEANIQUE, Sea surface temperature, ALIS current, 13. Climate action, Climatology, SIMULATION, Remote Sensing Technology, COURANT MARIN, Environmental science, Hydrography, IMPACT SUR L'ENVIRONNEMENT, Environmental Monitoring
Abstract

International audience; The upwelling events that follow strong trade wind episodes have been described in terms of their remarkable signature in the sea surface temperature southwest off New Caledonia. Upwelling brings deeper, and colder waters to the surface, causing 2-4 °C drops in temperature in a few hours, followed by a slower relaxation over several days. Upwelling may sporadically bring nutrients to the surface under certain conditions, and increase the biological productivity. Two multidisciplinary hydrographic cruises allow the impact of upwelling on the chemical and biological properties of the water to be documented. Both cruises took place in austral summer (December 2004 and December 2005), but the first cruise occurred during a strong upwelling event, while the second cruise occurred in calm conditions. The water properties and planktonic composition show important contrasts, with a strong southeastward current (the "ALIS current of New Caledonia") competing with the upwelling system. Our analysis suggests that, while observed productivities are far less than those of typical upwelling systems, some wind events in New Caledonia may contribute to biological activity. A currentmeter mooring, deployed during the second cruise, documents the ocean response to a changing wind field and the local impact of upwelling on currents and temperatures on the water column. The results are discussed, with the help of climatology, Argo float profiler data, satellite data and of a high-resolution numerical simulation.

Published
2010

4. New Caledonia tropical lagoons : an overview of multidisciplinary investigations

Author

Laure Carassou, R. Le Borgne, E. Rolland, Dominique Ponton, Grenz, Christian (ed.), and Le Borgne, Robert (ed.)

Subjects
Chlorophyll, Chlorophyll a, Time Factors, Population Dynamics, Wind, Aquatic Science, Environment, Oceanography, Zooplankton, ABONDANCE, POISSON MARIN, chemistry.chemical_compound, Food Preferences, Water column, LAGON, New Caledonia, Animals, Seawater, Ecosystem, Population Density, geography, geography.geographical_feature_category, Pacific Ocean, Terrigenous sediment, IMPACT DE L'ENVIRONNEMENT, Chlorophyll A, Fishes, Temperature, Estuary, Coral reef, Biodiversity, Plankton, Anthozoa, Pollution, Fishery, RECIF CORALLIEN, chemistry, Environmental science, ZOOPLANCTON, LARVE, Bay, RELATION PREDATEUR PROIE
Abstract

The distribution of zooplanktonic prey of fish larvae was examined in three bays and two lagoonal stations in the Southwest lagoon of New Caledonia. Water column conditions were characterized by increasing chlorophyll a and particulate organic matter (POM) concentrations from the lagoon to the estuarine bay. The mean zooplankton settled volume and total density were significantly higher in the estuarine bay, reaching 35.1 mL m(-3) and 3.5 x 10(5) individuals m(-3), respectively. The total zooplankton density also progressively increased along the sampling period. The composition of assemblages differed between the lagoon and the bays, and was similar in the three bays. Wind speed, surface temperature, chlorophyll a and POM explained these variations, as revealed by a co-inertia analysis (COIA). The prey preferred by fish larvae, i.e. small crustaceans and small copepods, were more abundant in bays. Sheltered bays, most influenced by terrigenous inputs, are likely to provide the best feeding conditions.

Published
2010

5. Hydrography and plankton temporal variabilities at different time scales in the southwest lagoon of New Caledonia: a review

Author

Pascal Douillet, Robert Le Borgne, Renaud Fichez, Jean-Pascal Torréton, UR 103 Camélia, Institut de Recherche pour le Développement ( IRD ), Grenz, Christian (ed.), and Le Borgne, Robert (ed.)

Subjects
DYNAMICS, SALINITE, PACIFIC, Time Factors, Context (language use), METEOROLOGIE, Aquatic Science, Oceanography, LAGON, New Caledonia, medicine, Water Movements, Seawater, Precipitation, WEST LAGOON, Ecosystem, Shore, TEMPERATURE DE SURFACE, geography, geography.geographical_feature_category, [ SDU.STU.OC ] Sciences of the Universe [physics]/Earth Sciences/Oceanography, Temperature, Tropics, Pelagic zone, Plankton, Seasonality, INPUTS, medicine.disease, SEASONAL-VARIATIONS, Pollution, VARIATION INTERANNUELLE, Climatology, BAY, Environmental science, Seasons, Hydrography, PLANCTON, COMMUNITIES, CORAL-REEF LAGOON
Abstract

International audience; The New Caledonia SW lagoon is wide (5-20 nautical miles) and semi-closed. It is influenced by both the open ocean and the high island within a meteorological context subject to seasonal, inter-annual and longer term variations. The short-term variability (>1 day) of meteorological, hydrographical and planktonic parameters is illustrated by a 5-month long time series and is linked to local or remote wind, and precipitation. Seasonal and inter-annual variabilities, inferred from a 10-year long station by spectral analysis, appear clearly for all parameters. Seasonality is the main scale of variability as the island lies near the tropic of Capricorn. Inter-annual variability of a 3-4 year periodicity is poorly related to the Southern oscillation index (an equatorial climatic index), stressing the need for a separate tropical index. Long term trends appear on several parameters but their reliability depends on the length of the records. Considering only the longest records (1958-2005), surface temperature appears to have increased since the end of the 1960s in Noumea area. Finally, as a result of greater terrestrial influence, shallower depths, and longer water turnover times close to shore, the temporal variability amplitude decreases from the shore to the barrier reef.

Published
2010

6. Integrated coastal zone management perspectives to ensure the sustainability of coral reefs in New Caledonia

Author

Marc Léopold, Gilbert David, Guy Fontenelle, Jocelyne Ferraris, Pascal Dumas, Jean-Brice Herrenschmidt, Écologie et santé des écosystèmes (ESE), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), French National Program for Coastal Environment (PNEC), Grenz, Christian (ed.), and Le Borgne, Robert (ed.)

Subjects
0106 biological sciences, CONSERVATION DE LA NATURE, Coral reefs, 010501 environmental sciences, Oceanography, 01 natural sciences, LAGON, Environmental protection, Nickel, MESH: Nickel, MESH: Animals, MESH: Ecosystem, Integrated coastal zone management, Nature reserve, Governance, geography.geographical_feature_category, Environmental resource management, Coral reef, Lagoon, Anthozoa, MESH: Mining, Pollution, Geography, MESH: Water Pollutants, Chemical, Government, impact, MESH: Conservation of Natural Resources, Mainland China, Civil society, Conservation of Natural Resources, MESH: Government, Mine, Aquatic Science, Mining, PATRIMOINE MONDIAL, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, New Caledonia, Island economy, GESTION DE L'ENVIRONNEMENT, Animals, pacific islands, 14. Life underwater, World heritage, Reef, Ecosystem, 0105 earth and related environmental sciences, Sustainable development, AIRE MARINE PROTEGEE, business.industry, INDUSTRIE MINIERE, 010604 marine biology & hydrobiology, ZONE COTIERE, Marine reserve, MESH: New Caledonia, RECIF CORALLIEN, MESH: Anthozoa, fisheries, Sustainability, business, GESTION INTEGREE, Water Pollutants, Chemical
Abstract

Based on a pluridisciplinary research programme on New Caledonia's lagoon (2004-2008), this paper addresses economic, ecological and political issues in order to implement integrated coastal zone management (ICZM) in this French Pacific territory. The nickel mining industry constitutes the core of the re-balancing economic and social strategy between the Northern and Southern provinces. But major impacts on the coastal environment of metal-processing plants, harbours, and decades of mine exploitation have released a controversy. A short diachronic analysis suggests that such environmental concerns prompted the emergence of collective actions to among civil society, customary and institutional stakeholders. The inscription of New Caledonia lagoon and reef areas in the UNESCO World Heritage List in 2008 would be both an outcome and a catalyst of this on-going process. Looking beyond the reefs towards the mainland and watersheds for the construction of local socio-ecological systems, we assume that the current stakes could result in the initiation of ICZM in New Caledonia.

Published
2010

7. Metal and metalloid bioaccumulation in the Pacific blue shrimp Litopenaeus stylirostris (Stimpson) from New Caledonia: laboratory and field studies

Author

Mohamed M. Eltayeb, Laetitia Hédouin, Marc Metian, Michel Warnau, Jean-Louis Teyssié, Paco Bustamante, Chantal Mugnier, Thomas Lacoue-Labarthe, LIttoral ENvironnement et Sociétés - UMRi 7266 (LIENSs), Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Marine Environment Laboratories [Monaco] (IAEA-MEL), International Atomic Energy Agency [Vienna] (IAEA), IUCN - West Asia/Middle East (WAME) (ICUN), Arabie Saoudite, Centre de Recherche sur les Ecosystèmes Littoraux Anthropisés (CRELA), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de La Rochelle (ULR)-Centre National de la Recherche Scientifique (CNRS), Caractérisation et modélisation des échanges dans des lagons soumis aux influences terrigènes et anthropiques (CAMELIA), Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie])-Institut de Recherche pour le Développement (IRD [Guyane]), Laboratoire d'Aquaculture de Calédonie (LAC), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Grenz, Christian (ed.), Le Borgne, Robert (ed.), LIttoral ENvironnement et Sociétés (LIENSs), La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS), and Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-La Rochelle Université (ULR)-Centre National de la Recherche Scientifique (CNRS)

Subjects
0106 biological sciences, Biokinetics, Hepatopancreas, 010501 environmental sciences, Oceanography, 01 natural sciences, biokinetics, contamination, Moulting, Metalloids, Cadmium, biology, Decapoda, Ecology, BIOACCUMULATION, 16. Peace & justice, Pollution, radiotracers, Shrimp, Intestines, CONTAMINATION, CREVETTE, Radiotracers, Metals, Environmental chemistry, Bioaccumulation, METAL, [SDV.TOX.ECO]Life Sciences [q-bio]/Toxicology/Ecotoxicology, TRACABILITE, Penaeidae, animal structures, ANALYSE DE LABORATOIRE, moulting, chemistry.chemical_element, metals, Crustacean, Aquatic Science, New Caledonia, Metals, Heavy, Animals, CONTENU STOMACAL, 14. Life underwater, Shellfish, 0105 earth and related environmental sciences, 010604 marine biology & hydrobiology, fungi, biology.organism_classification, chemistry, crustacean, Water Pollutants, Chemical
Abstract

The present work aimed at better understanding metal and metalloid bioaccumulation in the edible Pacific blue shrimp Litopenaeus stylirostris, using both laboratory and field approaches. In the laboratory, the bioaccumulation kinetics of Ag, Cd, Co, Cr, and Zn have been investigated in shrimp exposed via seawater and food, using the corresponding gamma-emitting radiotracers (Ag-110m, Cd-109, Co-57, Cr-51, and Zn-65) and highly sensitive nuclear detection techniques. Results showed that hepatopancreas and intestine concentrated the metals to the highest extent among the blue shrimp organs and tissues. Moulting was found to play a non negligible detoxification role for Co, Cr and, to a lesser extent, Zn. Metal retention by L stylirostris widely varied (from a few days to several months), according to the element and exposure pathway considered (a given metal was usually less strongly retained when ingested with food than when it was taken up from the dissolved phase). In the field study, Ag, As, Cd, Co, Cr, Cu, Mn, Ni, and Zn were analysed in shrimp collected from a New Caledonian aquaculture pond. Metal concentrations in the shrimp muscles were generally relatively low and results confirmed the role played by the digestive organs and tissues in the bioaccumulation/storage/detoxification of metals in the Pacific blue shrimp. Preliminary risk considerations indicate that consumption of the shrimp farmed in New Caledonia is not of particular concern for human health. (C) 2010 Elsevier Ltd. All rights reserved.

Published
2010

8. Geographical aspects of informal reef fishery systems in New Caledonia

Author

Nicolas Guillemot, Isabelle Jollit, Jocelyne Ferraris, Gilbert David, Marc Léopold, Pascale Chabanet, J.M. Lebigre, Grenz, Christian (ed.), and Le Borgne, Robert (ed.)

Subjects
Rural Population, Marine conservation, Geographic information system, Urban Population, SYSTEME D'INFORMATION GEOGRAPHIQUE, Fishing, Fisheries, Aquatic Science, Oceanography, EFFORT DE PECHE, PECHE MARITIME, ECONOMIE DES PECHES, New Caledonia, Animals, Humans, Reef, Recreation, ANALYSE STATISTIQUE, geography, geography.geographical_feature_category, Geography, business.industry, Subsistence agriculture, Coral reef, Pollution, Fishery, RECIF CORALLIEN, CAPTURE, Socioeconomic Factors, Sustainability, business
Abstract

The coral reefs in New Caledonia have long been used by the local population for subsistence as well as commercial and recreational purposes. The impact of informal fisheries on reef ecosystems illustrated the idiosyncrasies of New Caledonian fisheries in the southwest Pacific. This paper compared informal fishery systems on the southwest coast (close to the capital and economic center of the country) and the northwest coast (where an industrial mining complex has been under development) of New Caledonia to analyze their spatial structure and characteristics. Four geosystems were defined. These depended on the natural, social and economical environments as well as management strategies. The way of life of the fishers proved to be a major factor in how the informal fishery systems were structured. Our observations suggested that ongoing socio-economic changes in New Caledonia have shaped informal fishing activities since the 1900s. The findings from this study validate the suitability of spatial approaches to coral reef fisheries and provide local stakeholders with original management clues for marine resources sustainability.

Published
2010

9. Biogeochemical typology and temporal variability of lagoon waters in a coral reef ecosystem subject to terrigeneous and anthropogenic inputs (New Caledonia)

Author

Philippe Gérard, Renaud Fichez, F. Gutierrez, Sylvain Ouillon, Aymeric Jouon, Sandrine Chifflet, Christian Grenz, Pascal Douillet, Grenz, Christian (ed.), Le Borgne, Robert (ed.), Caractérisation et modélisation des échanges dans des lagons soumis aux influences terrigènes et anthropiques (CAMELIA), Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie])-Institut de Recherche pour le Développement (IRD [Guyane]), Centre d'océanologie de Marseille (COM), Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), IRD, Universidad Autonoma Metropolitana Iztapalapa (IRD), Universidad Autonoma Metropolitana - Iztapalapa, OPLC, Institut méditerranéen d'océanologie (MIO), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie]), Universidad Autonoma Metropolitana Iztapalapa (DCBS), DCBS, Echanges Côte-Large (ECOLA), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Océanographie Physique et Biogéochimique (LOPB), Caractérisation et modélisation des échanges dans des lagons soumis aux influences terrigènes et anthropiques ( CAMELIA ), Institut de Recherche pour le Développement ( IRD [Nouvelle-Calédonie] ) -Institut de Recherche pour le Développement ( IRD [Guyanne] ), Centre d'océanologie de Marseille ( COM ), Centre National de la Recherche Scientifique ( CNRS ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Université de la Méditerranée - Aix-Marseille 2, IRD, Universidad Autonoma Metropolitana Iztapalapa ( IRD ), Institut méditerranéen d'océanologie ( MIO ), Centre National de la Recherche Scientifique ( CNRS ) -Université de Toulon ( UTLN ) -Aix Marseille Université ( AMU ) -Institut de Recherche pour le Développement ( IRD ) -Centre National de la Recherche Scientifique ( CNRS ) -Université de Toulon ( UTLN ) -Aix Marseille Université ( AMU ) -Institut de Recherche pour le Développement ( IRD ), Institut de Recherche pour le Développement ( IRD [Nouvelle-Calédonie] ), Universidad Autonoma Metropolitana Iztapalapa ( DCBS ), ECOLA LEGOS, Laboratoire d'études en Géophysique et océanographie spatiales ( LEGOS ), Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National d'Etudes Spatiales ( CNES ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire Midi-Pyrénées ( OMP ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National d'Etudes Spatiales ( CNES ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire Midi-Pyrénées ( OMP ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d'Océanographie Physique et Biologique ( LOPB ), Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), and Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)

Subjects
Chlorophyll, 0106 biological sciences, SALINITE, Time Factors, 010504 meteorology & atmospheric sciences, SEL NUTRITIF, Oceanography, 01 natural sciences, Trophic status, CYCLE BIOGEOCHIMIQUE, VARIATION TEMPORELLE, LAGON, Cluster Analysis, Water pollution, TEMPERATURE, Trophic level, geography.geographical_feature_category, [ SDU.STU.OC ] Sciences of the Universe [physics]/Earth Sciences/Oceanography, Ecology, IMPACT DE L'ENVIRONNEMENT, NIVEAU TROPHIQUE, Coral reef, Anthozoa, Pollution, Seasons, Environmental Monitoring, Biogeochemical cycle, Aquatic Science, Coral reef lagoon, New Caledonia, Animals, Seawater, Ecosystem, 14. Life underwater, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, geography, Chlorophyll A, 010604 marine biology & hydrobiology, Biogeochemistry, Temporal variability, Nutrients, 15. Life on land, RECIF CORALLIEN, Typology, 13. Climate action, Environmental science, Spatial variability, Hydrology, Eutrophication, Water Pollutants, Chemical
Abstract

International audience; Considering the growing concern about the impact of anthropogenic inputs on coral reefs and coral reef lagoons, surprisingly little attention has been given to the relationship between those inputs and the trophic status of lagoon waters. The present paper describes the distribution of biogeochemical parameters in the coral reef lagoon of New Caledonia where environmental conditions allegedly range from pristine oligotrophic to anthropogenically influenced. The study objectives were to: (i) identify terrigeneous and anthropogenic inputs and propose a typology of lagoon waters, (ii) determine temporal variability of water biogeochemical parameters at time-scales ranging from hours to seasons. Combined ACP-cluster analyses revealed that over the 2000 km2 lagoon area around the city of Nouméa, "natural" terrigeneous versus oceanic influences affecting all stations only accounted for less than 20% of the spatial variability whereas 60% of that spatial variability could be attributed to significant eutrophication of a limited number of inshore stations. ACP analysis allowed to unambiguously discriminating between the natural trophic enrichment along the offshore-inshore gradient and anthropogenically induced eutrophication. High temporal variability in dissolved inorganic nutrients concentrations strongly hindered their use as indicators of environmental status. Due to longer turn over time, particulate organic material and more specifically chlorophyll a appeared as more reliable nonconservative tracer of trophic status. Results further provided evidence that ENSO occurrences might temporarily lower the trophic status of the New Caledonia lagoon. It is concluded that, due to such high frequency temporal variability, the use of biogeochemical parameters in environmental surveys require adapted sampling strategies, data management and environmental alert methods.

Published
2010

10. New Caledonia tropical lagoons : an overview of multidisciplinary investigations

Author

A Carroll, Mehdi Adjeroud, J M Fernandez, Peter Harrison, Lucie Penin, Biologie et écologie tropicale et méditerranéenne [2007-2010] (BETM), Université de Perpignan Via Domitia (UPVD)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), ARC Centre of Excellence for Coral Reef Studies (CoralCoE), James Cook University (JCU), Grenz, Christian, and Le Borgne, Robert

Subjects
0106 biological sciences, Cnidaria, STRUCTURE DU PEUPLEMENT, Fringing reef, Coral, [SDE.MCG]Environmental Sciences/Global Changes, Scleractinia, Environment, Aquatic Science, Oceanography, 010603 evolutionary biology, 01 natural sciences, ABONDANCE, SUBSTRAT, ANALYSE DE CORRESPONDANCE, New Caledonia, LAGON, Animals, 14. Life underwater, JUVENILE, Reef, Ecosystem, Population Density, geography, geography.geographical_feature_category, biology, Ecology, 010604 marine biology & hydrobiology, IMPACT DE L'ENVIRONNEMENT, Coralline algae, Biodiversity, Coral reef, Anthozoa, biology.organism_classification, CORAIL, Pollution, Species richness
Abstract

International audience; We investigated the spatial distribution of adult and juvenile coral assemblages in the southwestern lagoon of New Caledonia, from disturbed fringing reefs within bays, to oceanic barrier reefs. Generic richness, abundance, and percent cover were highly variable at this scale, but no clear cross-shelf gradient was found. Rather, community composition was more related to reef biotopes. Correlations and canonical correspondence analyses revealed that composition and abundance of coral assemblages were related to substrate types (cover of turf algae and cover of encrusting coralline algae), but not to water quality or metal concentrations in sediments. We found a strong relationship between juvenile and adult distribution for all dominant genera, which suggests that recruitment processes are also a major factor structuring these populations. The densities of juveniles and their proportion in the coral assemblages were relatively low, which implies that replenishment capacities and potential for recovery are probably limited for these reefs.

Published
2010

11. Inherent optical properties and satellite retrieval of chlorophyll concentration in the lagoon and open ocean waters of New Caledonia

Author

Sylvain Ouillon, Cécile Dupouy, Jacques Neveux, Robert Frouin, Guillaume Dirberg, Sébastien Hochard, Hiroshi Murakami, Grenz, Christian (ed.), Le Borgne, Robert (ed.), Institut méditerranéen d'océanologie (MIO), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'océanographie biologique de Banyuls (LOBB), Observatoire océanologique de Banyuls (OOB), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Echanges Côte-Large (ECOLA), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Scripps Institution of Oceanography (SIO - UC San Diego), University of California [San Diego] (UC San Diego), University of California (UC)-University of California (UC), EORC, Japan Aerospace Exploration Agency [Tsukuba] (JAXA), Mécanismes adaptatifs : des organismes aux communautés, Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Scripps Institution of Oceanography (SIO), and University of California-University of California

Subjects
0106 biological sciences, OC4v4 algorithm, Chlorophyll, Optical Phenomena, 010504 meteorology & atmospheric sciences, Backscattering, Oceanography, 01 natural sciences, chemistry.chemical_compound, LAGON, ABSORPTION, Turbidity, Absorption (electromagnetic radiation), MODELE BIO OPTIQUE, media_common, biology, Lagoon, Satellite Communications, Pollution, CHLOROPHYLLE, Trichodesmium, Ocean color, Algorithms, Environmental Monitoring, media_common.quotation_subject, Aquatic Science, Absorption, New Caledonia, OCEAN, ALGORITHME, Phytoplankton, Seawater, 14. Life underwater, Bio-optical model, Ecosystem, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, Pacific Ocean, DONNEES SATELLITE, 010604 marine biology & hydrobiology, Remote sensing reflectance, COULEUR, Pelagic zone, biology.organism_classification, REFLECTANCE, chemistry, Environmental science, Bio-optical properties
Abstract

International audience; The retrieval of chlorophyll-a concentration from remote sensing reflectance (Rrs) data was tested with the NASA OC4v4 algorithm on the inner New Caledonian lagoon (Case 2) and adjacent open ocean (Case 1) waters. The input to OC4v4 was Rrs measured in situ or modeled from water's inherent optical properties (2001-2007). At open ocean stations, backscattering and absorption coefficients were correlated with chlorophyll (R2 = 0.31-0.51, respectively), in agreement with models for Case 1 waters. Taking spectrofluorometric measurement as reference, the OC4v4 model leads to an average underestimation of 33% of the chlorophyll concentration. For the lagoon waters, OC4v4 performed inadequately because the backscattering coefficient, highly correlated with turbidity and suspended matter (R2 = 0.98), was poorly correlated to chlorophyll (R2 = 0.42). The OC4v4 performance was better in deep lagoon waters for stations with a TDT index (Tchla × depth/turbidity) higher than 19 mg m−2 NTU−1 (R2 = 0.974, bias = 10.2%). Global Imager Rrs provided a good estimate of Tchla (R2 = 0.79, N = 28) in the deeper part of the lagoon.

Published
2010

12. New Caledonia tropical lagoons : an overview of multidisciplinary investigations

Author

Anne Leroy, Patrick Marchesiello, Nicolas C. Jourdain, Jérôme Lefèvre, Christophe E. Menkès, Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie]), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Météo-France Direction Interrégionale de la Nouvelle Calédonie (DIRNC), Météo-France, Echanges Côte-Large (ECOLA), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Laboratoire des Écoulements Géophysiques et Industriels [Grenoble] (LEGI), Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Météo France [Nouméa], Météo France, Grenz, Christian (ed.), and Le Borgne, Robert (ed.)

Subjects
VARIATION SAISONNIERE, 010504 meteorology & atmospheric sciences, Atmospheric circulation, VENT, Mesoscale meteorology, Wind, 010501 environmental sciences, Aquatic Science, Oceanography, Atmospheric sciences, 01 natural sciences, CLIMATOLOGIE, Mesoscale models, MODELE, New Caledonia, Synoptic scale meteorology, Water Movements, South Pacific convergence zone, 14. Life underwater, INTERACTION OCEAN ATMOSPHERE, Weather, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, Orographic lift, ANALYSE STATISTIQUE, Geography, Ocean current, Scatterometer winds, Reproducibility of Results, Madden–Julian oscillation, Jet stream, Models, Theoretical, Pollution, CIRCULATION OCEANIQUE, 13. Climate action, Climatology, Weather regime, Island-scale circulation, Environmental Monitoring
Abstract

International audience; The local climate and island-scale circulation around New Caledonia is investigated using a 4-km resolution mesoscale atmospheric model in concert with QuikSCAT scatterometer winds at 12.5-km resolution. The mesoscale atmospheric weather regimes are first examined through an objective classification applied to the remote sensed winds for nine warm seasons from 1999 to 2008. Four main weather types are identified. Their corresponding synoptic-scale circulation reveals that they are strongly discernable through the position and intensity of the South Pacific Convergence zone (SPCZ), the mid-latitude systems, and the subtropical jet stream. The link between the mesoscale weather types and the two dominant large-scale modes of variability, namely the Madden-Julian Oscillation (MJO) and the El Niño-Southern Oscillation (ENSO), is also described in terms of their influence on the occurrence of each weather type. It shows that their occurrence is significantly controlled by both MJO and ENSO, through modulation of the SPCZ. The large-scale modes of variability are scaled down to island-scale circulation through synoptic and mesoscale regimes, and are eventually modulated by orographic and thermal control. The island-scale circulation is inferred in this study by applying the compositing method to both observed and simulated winds. Their comparison clearly shows the ability of the mesoscale model to capture the local circulation and its spatial and temporal variability. A scaling analysis conducted from the simulated atmospheric parameters shows that the mountain range of New Caledonia is hydrodynamically steep. As a result of trade-wind obstruction by the mountainous island, the flow is shaped by coastally trapped mesoscale responses, i.e., blocking, flow splitting and corner winds, with a spatial scale of about 150 km. Two main obstacles, Mont Panié and Mont Humboldt play a significant role on the dynamical behavior of the low-level flow, while the diurnal heating cycle in the vicinity of the Mainland strongly modulates the local circulation. Moreover, nocturnal drainage flow of cold air occurs on the leeside slope of Mont Humboldt and inhibits vertical mixing over the ocean, which results in a deceleration of surface winds.

Published
2010

13. Coastal upwelling, circulation and heat balance around New Caledonia's barrier reef

Author

Patrick Marchesiello, Christophe E. Menkès, Xavier Couvelard, Andres Vega, Jérôme Lefèvre, Echanges Côte-Large (ECOLA), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Institut méditerranéen d'océanologie (MIO), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Grenz, Christian (ed.), and Le Borgne, Robert (ed.)

Subjects
Hot Temperature, 010504 meteorology & atmospheric sciences, COURANT GEOSTROPHIQUE, Wind stress, UPWELLING, Wind, Aquatic Science, Oceanography, 01 natural sciences, Geostrophic current, New Caledonia, Water Movements, Animals, 14. Life underwater, FLUX THERMIQUE, Ecosystem, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, 010505 oceanography, Advection, Ocean current, ETUDE REGIONALE, ZONE COTIERE, Regional ocean circulation, Models, Theoretical, Anthozoa, Pollution, Current (stream), CIRCULATION OCEANIQUE, 13. Climate action, Climatology, SIMULATION, Upwelling, Seasons, Surface water, Geology, Geostrophic wind, Environmental Monitoring, Coastal upwelling
Abstract

International audience; An outstanding characteristic of New Caledonia upwelling is that most events appear limited to the southern half of the western barrier reef. This north-south difference cannot be explained by alongshore variability of the projected wind stress and no strong evidence for alternative explanations has been proposed. A major objective of this paper is to provide the first dynamical analysis of New Caledonia upwelling and its regional environment, based on numerical simulations. Coastal upwelling around New Caledonia is shown to be modulated by a system of geostrophic currents interacting with the island mass. Upwelling velocities are weaker than expected from the two-dimensional Ekman theory, as Ekman divergence is balanced by "coastal geostrophic convergence". The cooling effect of upwelling is also attenuated by alongshore transport of warm water by the Alis current, reminiscent of the Leeuwin current off Western Australia. Nevertheless, coastal upwelling can locally modify the large-scale surface water heat budget, dominated by meridional advection warming and surface cooling. The upwelled waters appear to be mostly of western origin and are transported below the surface by the Subtropical Counter Current before upwelling off New Caledonia. This appears in sharp contrast with the eastern barrier reef where the general warming by meridional advection of tropical surface waters is accentuated by the vigorous western boundary type Vauban current.

Published
2010

14. New Caledonia tropical lagoons : an overview of multidisciplinary investigations

Author

R. Le Borgne, Christian Grenz, Renaud Fichez, Jean-Pascal Torréton, Grenz, Christian (ed.), Le Borgne, Robert (ed.), Laboratoire d'Océanographie Physique et Biologique ( LOPB ), Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), PNEC, Laboratoire d'Océanographie Physique et Biogéochimique (LOPB), and Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Conservation of Natural Resources, 010504 meteorology & atmospheric sciences, PRODUCTION PRIMAIRE, [SDE.MCG]Environmental Sciences/Global Changes, Pilot Projects, PROGRAMME DE RECHERCHE, 010501 environmental sciences, Aquatic Science, Oceanography, 01 natural sciences, CYCLE BIOGEOCHIMIQUE, New Caledonia, LAGON, Multidisciplinary approach, Environmental protection, Animals, RECHERCHE PLURIDISCIPLINAIRE, 14. Life underwater, Ecosystem, 0105 earth and related environmental sciences, Tropical Climate, business.industry, Environmental resource management, Biodiversity, Pollution, [ SDE.MCG ] Environmental Sciences/Global Changes, CIRCULATION OCEANIQUE, Environmental science, Interdisciplinary Communication, business, PLANCTON
Abstract

International audience; résumé

Published
2010

15. New Caledonia tropical lagoons : an overview of multidisciplinary investigations

Author

Christian Grenz, Renaud Fichez, Olivier Pringault, Lionel Denis, Laboratoire d'Océanographie Physique et Biologique ( LOPB ), Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ), Grenz, Christian (ed.), Le Borgne, Robert (ed.), Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 ( LOG ), Université du Littoral Côte d'Opale-Université de Lille-Centre National de la Recherche Scientifique ( CNRS ), Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG), Centre National de la Recherche Scientifique (CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Institut national des sciences de l'Univers (INSU - CNRS), Laboratoire d'Océanographie Physique et Biogéochimique (LOPB), Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Nord])

Subjects
0106 biological sciences, [ SDU.OCEAN ] Sciences of the Universe [physics]/Ocean, Atmosphere, Geologic Sediments, CALCIUM-CARBONATE, VARIATION SAISONNIERE, SEL NUTRITIF, 010501 environmental sciences, Oceanography, SEDIMENT, 01 natural sciences, TROPICAL LAGOON, SOLUTE EXCHANGE, Water column, LAGON, BENTHIC NUTRIENT, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, [ SDU.STU.OC ] Sciences of the Universe [physics]/Earth Sciences/Oceanography, GREAT-BARRIER-REEF, MICROBIAL ACTIVITY, OXYGENE, Pollution, ORGANIC-MATTER, Benthic zone, Seasons, Biogeochemical cycle, Nitrogen, Benthic fluxes, Aquatic Science, Phosphates, New Caledonia, Sediment–water interface, Seawater, 14. Life underwater, DEEP-SEA, Ecosystem, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, Hydrology, Pacific Ocean, SULFATE REDUCTION, Silicates, 010604 marine biology & hydrobiology, Biogeochemistry, Sediment, Pelagic zone, Nutrients, 15. Life on land, Oxygen, VARIATION SPATIALE, Environmental science, Spatial variability, SOUTH-WEST LAGOON
Abstract

In order to quantify the spatial and seasonal variations of sediment oxygen consumption and nutrient fluxes, we performed a spatial survey in the south west lagoon of New Caledonia during the two major seasons (dry and wet) based on a network of 11 sampling stations. Stations were selected along two barrier reef to land transects representing most types of sediments encountered in the lagoon. Fluxes were measured using ex-situ sediment incubations and compared to sediment characteristics. Sediment oxygen consumption (SOC) varied between 500 and 2000 mu mol m(-2). depending on season and stations. Nutrient effluxes from sediment were highly variable with highest fluxes measured in muddy sediments near the coast. Inter-sample variability was as high as seasonal differences so that no seasonally driven temperature effect could be observed on benthic nutrient fluxes in our temperature range. Nutrient fluxes, generally directed from the sediment to the water column, varied between -5.0 and 70.0 mu mol m(-2) h(-1) for ammonia and between 2.5 and +12.5 mu mol m(-2) h(-1) for PO4 and NO2+3. SOC and nutrient fluxes were compared to pelagic primary production rates in order to highlight the tight coupling existing between the benthic and pelagic compartments in this shallow tropical lagoon. Under specific occasions of low pelagic productivity, oxygen sediment consumption and related carbon and nutrient fluxes could balance nearly all net primary production in the lagoon. These biogeochemical estimates point to the functional importance of sediment biogeochemistry in the lagoon of New Caledonia. (C) 2010 Elsevier Ltd. All rights reserved.

Published
2010

16. Circulation and suspended sediment transport in a coral reef lagoon: The south-west lagoon of New Caledonia

Author

Richard Laganier, Jérôme Lefèvre, Philippe Bonneton, Pascal Douillet, Franck Dumas, Serge Andréfouët, Patrick Marchesiello, J.P. Lefebvre, Olivier Magand, Sylvain Ouillon, Jean-Michel Fernandez, Renaud Fichez, Jean-Yves Panche, A. Bel Madani, Aymeric Jouon, P. Le Hir, C. Chevillon, R. Le Gendre, Echanges Côte-Large (ECOLA), Laboratoire d'études en Géophysique et océanographie spatiales (LEGOS), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National d'Études Spatiales [Toulouse] (CNES)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Universidad Autonoma Metropolitana Unidad Iztapalapa (UAM), Universidad Autonoma Metropolitana - Iztapalapa, Institut de Recherche pour le Développement (IRD [Nouvelle-Calédonie]), UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC), Observatoire aquitain des sciences de l'univers (OASU), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Centre National de la Recherche Scientifique (CNRS), Environnements et Paléoenvironnements OCéaniques (EPOC), Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), IFREMER (IFREMER), Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER), Pôle de recherche pour l'organisation et la diffusion de l'information géographique (PRODIG), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université Paris-Sorbonne (UP4)-École pratique des hautes études (EPHE)-Institut de Recherche pour le Développement (IRD)-Université Panthéon-Sorbonne (UP1), Laboratoire de physique hydrodynamique et sédimentaire (DYNECO/PHYSED), Instituto del Mar del Peru (IMARPE), Grenz, Christian (ed.), Le Borgne, Robert (ed.), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Universidad Autonoma Metropolitana, Unidad Iztapalapa (UAM), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Université Paris 1 Panthéon-Sorbonne (UP1)-Institut de Recherche pour le Développement (IRD)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris-Sorbonne (UP4)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), CLIPS, CHANG, Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), PNEC Grant NNG04F090G to Serge Andréfouët, Laboratoire de glaciologie et géophysique de l'environnement ( LGGE ), Observatoire des Sciences de l'Univers de Grenoble ( OSUG ), Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Centre National de la Recherche Scientifique ( CNRS ) -Observatoire des Sciences de l'Univers de Grenoble ( OSUG ), Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Université Joseph Fourier - Grenoble 1 ( UJF ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Grenoble Alpes ( UGA ) -Centre National de la Recherche Scientifique ( CNRS ), ECOLA LEGOS, Laboratoire d'études en Géophysique et océanographie spatiales ( LEGOS ), Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National d'Etudes Spatiales ( CNES ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire Midi-Pyrénées ( OMP ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Paul Sabatier - Toulouse 3 ( UPS ) -Centre National d'Etudes Spatiales ( CNES ) -Institut national des sciences de l'Univers ( INSU - CNRS ) -Observatoire Midi-Pyrénées ( OMP ) -Centre National de la Recherche Scientifique ( CNRS ), Universidad Autonoma Metropolitana Unidad Iztapalapa ( UAM ), Institut de Recherche pour le Développement ( IRD [Nouvelle-Calédonie] ), UMR 5805 Environnements et Paléoenvironnements Océaniques et Continentaux ( EPOC ), Observatoire aquitain des sciences de l'univers ( OASU ), Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -Université Sciences et Technologies - Bordeaux 1-Institut national des sciences de l'Univers ( INSU - CNRS ) -Centre National de la Recherche Scientifique ( CNRS ) -École pratique des hautes études ( EPHE ) -Centre National de la Recherche Scientifique ( CNRS ), Environnements et Paléoenvironnements OCéaniques ( EPOC ), IFREMER ( IFREMER ), Institut Français de Recherche pour l'Exploitation de la Mer ( IFREMER ), Pôle de recherche pour l'organisation et la diffusion de l'information géographique ( PRODIG ), Université Panthéon-Sorbonne ( UP1 ) -Institut de Recherche pour le Développement ( IRD ) -École pratique des hautes études ( EPHE ) -Université Paris-Sorbonne ( UP4 ) -Université Paris Diderot - Paris 7 ( UPD7 ) -Centre National de la Recherche Scientifique ( CNRS ), Laboratoire de physique hydrodynamique et sédimentaire ( DYNECO/PHYSED ), Instituto del Mar del Peru ( IMARPE ), and Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG)

Subjects
0106 biological sciences, Geologic Sediments, Salinity, Time Factors, 010504 meteorology & atmospheric sciences, Climate, Wind, Oceanography, SEDIMENT, 01 natural sciences, Resuspension, Turbidity, VARIATION TEMPORELLE, LAGON, [ SDU.STU.OC ] Sciences of the Universe [physics]/Earth Sciences/Oceanography, geography.geographical_feature_category, Temperature, MATIERE EN SUSPENSION, Coral reef, Anthozoa, Pollution, Turbidite, Suspended sediment, Seasons, Sediment transport, [ SDU.STU.GL ] Sciences of the Universe [physics]/Earth Sciences/Glaciology, Intertidal zone, Aquatic Science, Coral reef lagoon, New Caledonia, Water Movements, Animals, Seawater, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, 14. Life underwater, ANALYSE QUANTITATIVE, Particle Size, Reef, Ecosystem, [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography, 0105 earth and related environmental sciences, Hydrology, geography, Terrigenous sediment, 010604 marine biology & hydrobiology, Ocean current, TURBIDITE, Models, Theoretical, Inlet, VARIATION SPATIALE, Hydrodynamics, Environmental science, Sediment
Abstract

International audience; The south-west lagoon of New Caledonia is a wide semi-open coral reef lagoon bounded by an intertidal barrier reef and bisected by numerous deep inlets. This paper synthesizes findings from the 2000-2008 French National Program EC2CO-PNEC relative to the circulation and the transport of suspended particles in this lagoon. Numerical model development (hydrodynamic, fine suspended sediment transport, wind-wave, small-scale atmospheric circulation) allowed the determination of circulation patterns in the lagoon and the charting of residence time, the later of which has been recently used in a series of ecological studies. Topical studies based on field measurements permitted the parameterisation of wave set-up induced by the swell breaking on the reef barrier and the validation of a wind-wave model in a fetch-limited environment. The analysis of spatial and temporal variability of suspended matter concentration over short and long time-scales, the measurement of grain size distribution and the density of suspended matter (1.27 kg l−1), and the estimation of erodibility of heterogeneous (sand/mud, terrigenous/biogenic) soft bottoms was also conducted. Aggregates were shown to be more abundant near or around reefs and a possible biological influence on this aggregation is discussed. Optical measurements enabled the quantification of suspended matter either in situ (monochromatic measurements) or remotely (surface spectral measurements and satellite observations) and provided indirect calibration and validation of a suspended sediment transport model. The processes that warrant further investigation in order to improve our knowledge of circulation and suspended sediment transport in the New Caledonia lagoon as well as in other coral reef areas are discussed, as are the relevance and reliability of the numerical models for this endeavour.

Published
2010

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