Valérie Verdier est nommée Présidente-directrice générale de l’IRD (FRENCH ONLY)

Valérie Verdier vient d’être nommée Présidente-directrice générale de l’Institut de recherche pour...

« L’eau c’est le lien » (FRENCH ONLY)

Un article sur l’évolution de la gestion des réseaux d’eau en tribu kanak est paru en décembre...

L'UNC recrute un stagiaire dans le cadre du programme "Au fil de l'eau" (FRENCH ONLY)

L’Université de la Nouvelle-Calédonie recrute un stagiaire dans le cadre du programme "Au fil de l...

La Leptospirose dans le viseur de l'IPNC (FRENCH ONLY)

Le projet SpiRAL sur la leptospirose, porté par l’Institut Pasteur de Nouvelle-Calédonie (IPNC)...

Meilleurs voeux 2020 (FRENCH ONLY)

Meilleurs vœux ! Que cette année 2020 soit riche de projets et de belles découvertes…

1999- 2019 : L’Institut Agronomique Néo-Calédonien fête ses 20 ans ! (FRENCH ONLY)

 L’IAC travaille depuis 20 ans pour la protection et la valorisation de la biodiversité végétale et...

Vœux 2019 (French only)

Le CRESICA vous souhaite une excellente année 2019 !

NICKEL-CHROME

Ultramafic massifs rich in heavy metals like nickel (Ni) and chromium (Cr) make up nearly one third of New Caledonia. In areas where vegetation is degraded or absent, erosion processes result in the release of trace metals which are dispersed by air or by surface runoff. Nickel and chromium, including Cr6, are known for their toxicity in humans, notably causing cancers and allergies. Such trace metals may be present in creek and river waters and can contaminate drinking water catchment areas, thus constituting a potential source of exposure for communities in New Caledonia.

The NICKEL-CHROME project aims to:
•    assess the role of drinking water in the exposure of populations to nickel and chromium and, more specifically, Cr6 in New Caledonia.
•    propose hydrogeology-based arguments to explain the sources of exposure;
•    assess the role of weather events;
•    target at-risk populations.
Four research sites were selected: Isle of Pines, Houaïlou, Poya and Lifou, based on high concentrations of nickel and chromium in urine samples as recorded by the METEXPO program funded by the National Centre for Technological Research (CNRT).

 

Promoting organization

Dr Yann Barguil

Responsable scientifique
Mail
yann.barguil@cht.nc
Téléphone
209 845
Logo organisme
CHT
Project start date
June 2018
Estimated end date of project
June 2020
Accordéon

The METEXPO program, funded by the National Centre for Technological Research (CNRT), has identified high concentrations of nickel and chromium in urine samples from New Caledonian residents, particularly in young people aged under 18 and older people aged over 60, with geographic and seasonal variations also recorded.
 

Le Nickel, sous forme minerai  Crédit photo IRD NC
Nickel, in ore form

Photo credit IRD NC

Urinary concentrations of chromium exceeded reference values in the case of 47% of adults and 90% of children.
The most affected regions were: Kouaoua, Houaïlou, Poya, Hienghène, Touho and, unexpectedly, Lifou (no ultramafic massifs).
Urinary concentrations of nickel exceeded reference values in the case of 9% of adults and 13% of children. The most affected areas were the Isle of Pines, Belep, Houaïlou and Yaté.
In the findings set out by the METEXPO program, urinary concentrations of nickel or chromium were not explained by the proximity of mining operations. Data included in the prediction models - socio-economic and dietary data -, did not provide a satisfactory explanation of urinary trace metal concentrations.
Drinking water appeared to constitute one possible source of contamination affecting residents; contamination levels and links to urinary concentrations of nickel and chromium indicated that further study was necessary.

 

The main objectives of the Nickel-Chrome projects are to :
•    assess, as regards the general population, levels of exposure to nickel and chromium and, in particular, Cr6, in drinking water, together with any geographic and climatic variations.
•    analyse nickel and chromium concentrations in urine samples, according to gender, age, and geographic location;
•    study the correlation between nickel and chromium levels in drinking water and in urine samples.
Following the results of the Metexpo program four research sites were selected for the purposes of the Nickel-Chromium project: the Isle of Pines, Houaïlou, Poya and Lifou. The choice was based on the high levels of nickel or chromium in these municipalities as recorded by the METEXPO study, and the fact that they represent each of the three Provinces, as well as the East and West coasts of the Main Island.

Sites d'études

Sampling and analysis will be carried out at each site:
•    samples of drinking water will be taken from each water catchment located in each of the sites, and from water taps belonging to each person taking part in the study of urinary concentrations of nickel and chromium;
•    urinary analyses will be performed in clinics on samples provided by children or adults with a doctor’s appointment, subject to their informed consent.

This work, undertaken as part of the Nickel-Chromium project, will serve as preliminary research for a study the CNRT decided to conduct during the course of 2018. The CNRT research focus will be to achieve a better understanding of the factors involved in mobilisation of nickel (Ni) and chromium, including Cr6, in water, and to target areas where water plays a role in the presence of nickel and chromium trace metals in human urine. Public health authorities will be able to leverage the results to implement protective measures.

Four research sites were selected: Isle of Pines, Houaïlou, Poya and Lifou. Sampling began in 2018 at two sites (Houaïlou and the Isle of Pines) and will continue at two other sites in 2019 (Poya and Lifou). Given that research work began half way through 2018, sampling is scheduled to end half way through 2020.

Analyses des concentrations en nickel et chrome

At each research site, the Nickel-Chromium project will carry out
--   Sampling and analysis of drinking water. Samples will be taken from each water catchment within the site area and from water taps belonging to each person taking part in the study of urinary concentrations of nickel and chromium.

Samples from each catchment will be studied to determine:
 
o    the impact of weather events in levels of trace metals in the water. A sample will be taken during the dry season and another after a heavy rainfall episode. An estimated 150 samples per research site will be collected by an environmental epidemiologist
o    analysis of total dissolved nickel and chromium content (filtration at 0.45 μm) and dissolved hexavalent chromium (particularly toxic), carried out at LAMA-IRD under the supervision of a specialist in the analysis of water for trace metals.
o    concentrations of nickel and chromium, carried out by the ICP-MS
o    concentrations of chromium, Cr6, carried out using polarography.

--  Sampling and analysis of urinary concentrations of nickel and chromium

Research participants will be recruited at dispensaries, from amongst children or adults with a doctor’s appointment, and subject to their informed consent.
The following will be recruited at each centre :
•    30 children (3-17 years old)
•    40 adults aged 18-59 (20 men and 20 women)
•    30 people aged 60 or over.

Clinic staff will get people to fill in a general and dietary questionnaire to provide information on
•    Sociodemographic characteristics
•    Place of residence
•    Place of work or education,
•    Sources of drinking water and foods likely to contain trace metals.

Urine samples will be collected and transported to the Noumea CHT (hospital complex) via standard sample transfer channels.

An external laboratory will be in charge of assays to measure nickel and chromium levels in urine samples. The same laboratory will perform urinary creatinine assays, to ensure measurements of urinary trace metal concentrations are standardised.

Statistical analyses will be performed by environmental epidemiology consultants.
Median and quartile values for concentrations in water will be provided per site for each metal, and seasonal variations will be analysed. Concentrations in samples of tap water will be compared with samples from corresponding water catchments. Analyses of urinary concentrations of Ni and Cr will be performed and compared per research site, sex and age group. Finally, multivariate linear regression analyses will be performed to calculate the statistical relationship between nickel and chromium in tap water and in urine samples, using sociodemographic, dietary and environmental data as covariates.

Perspectives

Public health authorities will be able to leverage the results to implement protective measures. Furthermore, this study will form the basis for CHT-CNRS-IRD-BRGM DIMENC collaborative research work on the mobilisation of Ni and Cr6 trace metals in water, the research topic chosen for the next CNRT call for projects, and for targeting specific areas for advance field work.

 

The workshop of the programm "Au fil de l'eau" took place on 17 and 18 September 2019, at the UNC.

Tuesday 18 September was dedicated to the intermediate results of the "Au fil de l'eau" program (whose presentation is available on the french's page of the project). This restitution day was an opportunity to exchange on the various projects that make up the program, between research professionals, actors from the public, private and associative sectors working on these themes.

 

Partenaires associés

TREMOR

The composition of New Caledonia’s coastal soils is characterised by a high lateritic content due to decades of laterite mining, laterites being valued for their concentration of trace metals such as nickel, chromium, cobalt and manganese.
Mangroves contribute significant quantities of organic matter and therefore constitute a key reservoir for dissolved organic matter (DOM), which can be transported over significant distances into the ocean.
Existing surveys raise the question of the role of mangroves as a sink/source in terms of trace metal dynamics at the land-sea interface downstream from New Caledonia’s mining massifs.
The TREMOR project thus aims to provide answers to this question, based on the fluorescence properties of a fraction of DOM known as fluorescent dissolved organic matter (FDOM), in order to:

•    provide a better understanding of the origin, sources and sinks of FDOM detected in New Caledonia’s rivers and lagoon;
•    assess the influence of this FDOM on the dispersal and toxicity of trace metals in the coastline environment downstream from New Caledonia’s mining sites.

The TREMOR project will use validation of spectrofluorimetric data (fluorescence excitation–emission matrix or EEM) through in situ measurements using optical techniques (absorbance and fluorescence).
Once validated, spectrofluorimetric data can be used to characterise the various constituents of the FDOM.
Samples will be taken along river continua - mangroves - lagoon area, i.e. along 3 transects in the Koné lagoon.
TREMOR project findings will therefore provide significant information in terms of characterisation of coloured fluorescent dissolved organic matter (DOM) and assessment of its complexation capacity as regards trace metals.
If these findings prove convincing, this inexpensive technique can be more generally used in other contexts, both in salt water and fresh water environments.

 

Promoting organization

Cécile Dupouy

Responsable scientifique
Mail
cecile.dupouy@ird.fr
Téléphone
260 729
Logo organisme
IRD
Album photo
Le site amont mangrove du transect Témala du  projet TREMOR – copyright Cécile Dupouy
Exemple de mesures in situ de pH et conductivité dans l’un des sites mangrove du transect Coco
carte
Project start date
March 2018
Estimated end date of project
March 2021
Accordéon

The composition of New Caledonia’s coastal soils is characterised by a high lateritic content due to decades of laterite mining, laterites being valued for their concentration of trace metals such as nickel, chromium, cobalt and manganese.

Due to the dispersal and potential toxicity of these trace metals, mining could have a permanent impact on coastal ecosystems and affect their biodiversity (pelagic and benthic macro and micro organisms).

Since mangroves are located at the land-sea interface, they may act as a filter between the mining massifs and coastal ecosystems, including New Caledonia's lagoon, a substantial part of which is listed as a UNESCO World Heritage Site.

Mangroves contribute significant quantities of organic matter and therefore constitute a key reservoir for dissolved organic matter (DOM) which can be transported over considerable distances into the ocean.

DOM plays a key role in the oceanic carbon cycle, representing a significant fraction of terrestrial carbon. The coloured part of the dissolved organic matter (known as coloured dissolved organic matter or CDOM) is composed of fractions of carbon chains contained in a fraction smaller than 0.2 μm. Fractions which strongly absorb radiation at UV wavelengths.

Due to this optical property, CDOM acts as a solar umbrella for tropical corals and means that satellite remote sensing (water colour) can be used for large-scale quantification.

The complexation of heavy metals with dissolved organic matter can facilitate their dispersal into the lagoon. However, following complexation, heavy metal trace elements are less easily assimilated by living organisms; this reduces bioaccumulation and can endow DOM with detoxifying properties in the lagoon area.

 

The TREMOR project aims to round out research work recently initiated by MIO in New Caledonia, with a thesis on the “Dynamics of coloured and fluorescent dissolved organic matter in tropical lagoon areas in the South Pacific - New Caledonia: climatic and anthropogenic influences” (Martias, 2018) dealing with FDOM in the waters of New Caledonia’s lagoon, as part of the INSU EC2CO TREMOLO  project  (2012-2015), and as part of the CNRT DYNAMINE project (2015-2018).

Characterisation of FDOM components in river waters and their fate in the lagoon will be of use in:
•    specifying the origin of FDOM and how it makes its way from massifs to lagoon, using PARAFAC - a tool for the decomposition of complex signals;
•    achieving a clearer understanding of the influence of bacterial degradation processes during transit and early diagenesis of FDOM;
•    assessing the complexing abilities of the various FDOM constituents as regards heavy metal trace elements, for a more accurate estimate of the respective contributions of FDOM constituents in the dispersal and toxicity of trace metals along New Caledonia’s coastline.

Samples studied as part of the TREMOR project will be taken along river continua - mangroves - lagoon area, i.e. along 3 transects in the Koné lagoon:
•    the first transect follows the Témala river which flows into Chasseloup Bay. This first transect is associated with low mining-related impacts;
•    the second transect follows the Coco river which flows into Vavouto Bay. This second transect is associated with high mining-related impacts, with the KNS industrial site as a potential additional contributory factor;

 

prélevement

 

By comparison with these affected sites, the MOISE permanent observation station, located at Basse Caui opposite Maa Bay in the southwestern lagoon, has been regularly monitored by the IRD (monthly) for several years.

Other research sites can also be considered, including in connection with other projects funded by the CRESICA Au fil de l’eau Program (SEARSE project (Ifremer), for example).

 

The TREMOR project will have the advantage of a new-generation high sensitivity spectrofluorometer recently put into operation (October 2017) in New Caledonia (UMR IRD MIO). This instrument will perform analyses of FDOM and heavy metal trace element complexation experiments on fresh specimens (no preservation-related bias).

Spec

Furthermore, the recent commissioning of an ICP-MS device at LAMA (US IMAGO IRD) means that these spectrofluorimetric analyses can be locally coupled with analyses of heavy metal trace element concentrations in samples from waters under study.

Two factors will be taken into account during sampling campaigns.

• seasons: slow dynamics
The dry season corresponds to low outflows into the lagoon and the rainy season corresponds to high outflows into the lagoon. By taking this into account, observations relating to FDOM source tracking and dynamics, and also complexing abilities as regards heavy metal trace elements, can be repositioned in line with typical annual seasonal variations.

• tides: rapid dynamics
Tidal influence will be appraised through hourly sampling over 12 or 24 hours at an upstream mangrove station and a downstream mangrove station for each transect (Mounier et al, 2018). Comparison of findings from these series of timed samples will enable day-night effects to be separated from tide-related effects.

The TREMOR project sampling plan will require analysis of around 120 samples, including fifteen samples representative of habitats passed through, which will be used for heavy metal trace element complexation experiments.

Experiments testing the potential of spectrofluorimetric analysis in the identification of FDOM constituents have already been carried out:

•    in January 2018 in the Koné lagoon during a one-month assignment carried out by MIO aboard the vessel ALIS, as part of the UECOCOT project (monitoring cross-reef exchanges between lagoon and ocean at barrier reef breaks);
•    in March 2018 on sediments in the Koné lagoon sampled as part of the DYNAMINE project.
•    in July 2018, when Stéphane Mounier arrived for spectrofluorimetry training, an assignment targeting the same sites was carried out, concluding the series of analyses. These initial analyses were later supplemented by analyses carried out between March and June 2018 on samples collected along Coco and Témala river transects as part of Laura Boher’s  and as part of Marie Bessard’s Master 2 fieldwork course.
•    In July 2019 on the 2  Coco and Temala mangroves points with a 24h automatic sampler during a CRESICA mission of Stephane Mounier (48 samples)
•    The last mission will be in March 2020 during a CRESICA mission by Stephane Mounier in Coco and Temala rivers.

The process of interpreting findings from all these campaigns is underway. Works were presented at international symposiums WOMS 2018 in Toulon) and next at EGU 2020 in Vienna, Austria).

 

The workshop of the programm "Au fil de l'eau" took place on 17 and 18 September 2019, at the UNC.

Tuesday 18 September was dedicated to the intermediate results of the "Au fil de l'eau" program (whose presentation is available on the french's page of the project). This restitution day was an opportunity to exchange on the various projects that make up the program, between research professionals, actors from the public, private and associative sectors working on these themes.

 

Partenaires associés

MECAFLOC

The MECAFLOC project - mechanisms, influence of environmental physico-chemical properties and identification of new flocculants - is a research project led by the University of New Caledonia (UNC) and the Institute for Research and Development (IRD).
 
The aim of the MECAFLOC project is to obtain a clearer understanding of flocculation and of suspended mineral solids sedimentation mechanisms falling within the sphere of water purification.

 
The MECAFLOC project therefore aims, through research, to:
•    improve suspended solids separation techniques
•    implement models to evaluate suspended solids sedimentation rates in accordance with mineral characteristics, with a view to improving tailings pond design.
•    identify flocculant usage methodologies suitable for New Caledonia, with a specific focus on bioflocculants.

 

Promoting organization

Michael Meyer

Responsable scientifique
Research team / laboratory

ISEA

Mail
michael.meyer@univ-nc.nc
Téléphone
290 323
Logo organisme
UNC
Album photo
Méthode MECAFLOC
Méthode MECAFLOC
Méthode MECAFLOC
Méthode MECAFLOC
Méthode MECAFLOC
Project start date
August 2018
Estimated end date of project
August 2020
Accordéon

In New Caledonia, mining operations (recent or historic) play a key role in heightening the natural erosion process. This phenomenon, known as “red waters”, is characterised by a significant increase in sediment transport along rivers, particularly notable during rain events. This transport of suspended mineral solids such as iron oxide is responsible for downstream accumulations of silt in watersheds.
 

Particules en  suspensions observées par MET
Suspended particulate matter observed by MET

 

To mitigate the impact of suspended solids sedimentation at confluences of rivers and the lagoon, depending on salinity levels, tailings ponds are located on mining massifs along the river to facilitate the sedimentation process.

Since suspended solids associated with some substrates settle very slowly, such tailings ponds do not always prove effective. Flocculants and coagulants are therefore used to accelerate the sedimentation process. However, these have a greater or lesser effect depending on substrate characteristics and the physico-chemical conditions of the environment.

The aim of the MECAFLOC project is to obtain a clearer understanding of flocculation and suspended mineral solids sedimentation mechanisms in accordance with mineral characteristics and environmental physico-chemical properties (salinity, pH, etc.).

These sedimentation mechanisms vary depending on the environment and tend to significantly impact coastal areas. Today, we need to achieve greater control over related costs and impacts.

The MECAFLOC project aims to identify scientific responses targeting:
•    a better understanding of the dynamics of suspended solids sedimentation, according to the variable nature of soils and the physico-chemical environment of tailings ponds or areas where rivers and lagoon meet;
•    a knowledge of flocculant/suspended solids interactions according to mineral characteristics, taking into account the specific geological context of New Caledonia;
T

his project is being developed in line with the National Centre for Technical Research (CNRT) projects “Functioning of small mining catchments” and “Dynamine”, in which issues relating to the dynamics of suspended solids sedimentation are addressed.
SEARSE, a parallel project led by the IRD/UNC/IFREMER/AEL consortium since 2017, has been studying the behaviour of suspended solids in New Caledonia’s lagoon and assessing the impacts of mechanisms of aggregation/flocculation with organic matter.

 

The MECAFLOC project is based on laboratory research into in situ devices to monitor flocculation phenomena using optical measurements and filming of sedimentation fronts.

Tests will be carried out on various flocculant products to assess their effectiveness. There will be a strong focus on new natural molecules such as bioflocculants, which have a lower environmental impact than conventional chemical flocculants.

Test results will be used to model aggregation/flocculation mechanisms using the latest methods for simulation of nonlinear phenomena.
The ultimate aim of the project could be to propose methods for:
•    improving estimates of suspended solids sedimentation rates depending on mineral characteristics
•    improving tailings pond design

With, as a final goal: to come up with a flocculant use methodology suited to New Caledonia’s natural environments.

 

The workshop of the programm "Au fil de l'eau" took place on 17 and 18 September 2019, at the UNC.

Tuesday 18 September was dedicated to the intermediate results of the "Au fil de l'eau" program (whose presentation is available on the french's page of the project). This restitution day was an opportunity to exchange on the various projects that make up the program, between research professionals, actors from the public, private and associative sectors working on these themes.

 

 

Partenaires associés

SEARSE

For over 20 years, New Caledonia has been recognised as a global biodiversity hotspot possessing one of the world’s highest concentrations of endemic species. New Caledonia is encircled by the world’s largest coral reef complex.
 

Current economic, demographic and social changes in New Caledonia mean that coastlines and coastal environments are subject to increasing human-induced pressures.
The rivers play a key role in transporting sediments and dissolved constituents. Although these sedimentary loads are essential to the dynamics of coastal ecosystems, excess amounts may be harmful (nutrients, trace metals and other contaminants).
The SEARSE project aims to:
•    qualify and quantify sedimentary loads carried by rivers;
•    track them as they form sediment plumes in the lagoon around the Greater Noumea area;
To this end, analyses targeting concentrations of dissolved and particulate matter at outflows will be carried out, and the fate of sediment plumes in the lagoon environment around Greater Noumea will be monitored.
The SEARSE project will use the deterministic GR4J rainfall-runoff model, developed in 2017 by the LEAD team, and the Mars 3D hydrodynamic model developed by IFREMER.

 

Promoting organization

Hugues Lemonnier

Responsable scientifique
Research team / laboratory

Laboratoire LEAD

Mail
Hugues.Lemonnier@ifremer.fr
Téléphone
285 171
Logo organisme
Ifremer
Project start date
April 2018
Estimated end date of project
December 2020
Accordéon

New Caledonia is a vast territory possessing an exclusive economic zone (EEZ). Its maritime area comprises a variety of coral reef formations, lagoon areas, mangroves and very extensive expanses of ocean and seas.

New Caledonia’s exceptionally preserved marine biodiversity was recognised by the 2008 inscription of a majority of the lagoon and reef systems as a World Heritage Site (UNESCO).

For over a century, the mining industry has played a significant role in shaping the country’s landscapes and coastlines but there is an increasingly strong commitment to diversifying the economy and developing tourism and other sectors by leveraging factors such as the country’s attractiveness.

The vulnerability of these tropical ecosystems is a key issue both in terms of research and in terms of the challenges of achieving sustainable management (Territorial Innovation Strategy, 2015).

Any assessment of the environmental status of marine ecosystems must take into account the various human-induced pressures on the environment.

The fact that there is currently no quantification of human-induced pressures makes it very difficult to reach a clear understanding of the structuring processes which affect the integrity of this natural heritage and the related ecosystem services.
Adopting an ecosystem approach is vital to the implementation of an Integrated Coastal Ecosystems Management (ICZM) system.

 

Rivière la coulée –  copyright Elise Coignot
La Coulée river - Copyright Elise Coignot

 

Ultimately, the SEARSE project should make it possible to:

•    model the fate of dissolved compounds in the marine environment;
•    analyze the fate of some contaminants in the marine environment;
•    provide data allowing hydrologic landscapes in the lagoon around Greater Noumea to be defined and mapped.

With the goal of reaching a clearer understanding of:

•    ecosystem functioning in New Caledonia’s lagoon;
•    connectivity between lagoon fish communities;
•    initial sources of trace metal accumulation in the food chain.

The SEARSE project aims to conduct:

•    analyses of concentrations of dissolved and particulate matter at 4 outflows: the Dumbea, La Coulée, Rivière des Pirogues and Tontouta rivers;
•    monitoring of sediment plumes in the lagoon environment around Greater Noumea.

Analyses will identify essential characteristics for each river and quantify sedimentary loads carried by rivers into New Caledonia’s lagoon:

•    total suspended solids (TSS)
•    nutrients (ammonium, nitrates, phosphates and silicates)
•    metals (Cr, Ni, Fe, Mn, Cu, Zn and Al),
•    nitrogen, carbon and phosphorus,
•    organic material in dissolved and particulate form (including COD, CDOM and FDOM),
•    biological particles (bacteria and phytoplankton).

The monitoring process aims to:

•    establish maps of hydrological landscapes;
•    estimate the influence of fluvial loads on these landscapes.

 

carto dumbea, la coulée, la rivière des pirogues copyright Elise Coignot
Mapping of the Dumbea, La Coulée, Rivière des Pirogues rivers - Copyright Elise Coignot

 

Prélèvement avec bouteille Niskin  Copyright Hugues Lemonnier
Sampling using Niskin bottle

Copyright Hugues Lemonnier

The SEARSE project will conduct analyses based on the deterministic GR4J rainfall-runoff model to quantify sediment exports of dissolved and particulate matter from rivers.

This model, developed in 2017 by the IFREMER LEAD team, is designed to estimate river flows on an hourly time-step, from rain data.
These analyses were conducted in four Greater Noumea catchments (Desclaux et al., 2018).

A 300-m hydrodynamic model was developed around the Greater Noumea area to analyse the fate of river outflow waters.

Analyses will be linked to data rates from the GR4H model, with water characteristics at the 4 outflows (Dumbea, La Coulée, Rivière des Pirogues, La Tontouta).

The purchase of drifting buoys will allow tracking of the fate of the plumes and various materials that make up the lagoon.
There will be a special focus on the fate of genetic and functional diversity in microorganisms, excellent markers of environmental changes in the plumes.

This research work will be carried out as part of the assignment of an IFREMER expert from France.

 

Progress report on the monitoring of rivers at outflows in the south of New Caledonia, available at: https://archimer.ifremer.fr  

Boher L., Coignot E., Lopez E., Royer F., Lemonnier H., 2018. Monitoring fluorescent organic materials upstream from estuaries in the south of New Caledonia. End of contract report CSD IFREMER-LEAD. p. 38

Mot-Clé(s): Rivières, Matière organique fluorescente, dynamique


The workshop of the programm "Au fil de l'eau" took place on 17 and 18 September 2019, at the UNC.

Tuesday 18 September was dedicated to the intermediate results of the "Au fil de l'eau" program (whose presentation is available on the french's page of the project). This restitution day was an opportunity to exchange on the various projects that make up the program, between research professionals, actors from the public, private and associative sectors working on these themes.

 

 

Partenaires associés

ASSURPLUHYT

AssurPluHyT
Freshwater in Touho

Photo credit:  C. Goarant – IPNC

Major health issues, involving direct impacts on local populations, are closely linked to freshwater and the uses of freshwater.

The purpose of the ASSURPLUHYT project is to develop multidisciplinary approaches on health issues related to freshwater in New Caledonia, taking leptospirosis as a case study.

Leptospirosis is a zoonosis estimated to cause over one million cases and 60,000 deaths worldwide each year. Human leptospirosis is endemic in New Caledonia, with an average annual incidence of 45 cases per 100,000 pop., the North-East of the Main Island being particularly affected.

The vast majority of human cases of leptospirosis in New Caledonia are attributable to indirect exposure in an environment characterised by contaminated freshwater, particularly after heavy rain episodes.

Due to the major impact of leptospirosis in public health, notification of cases has been compulsory since 1991; leptospirosis has been studied for nearly 30 years at the Institut Pasteur in New Caledonia (IPNC).

 

The ASSURPLUHYT project aims to:

  • Characterise soil abiotic factors linked to the survival of pathogenic Leptospira;
  • Describe the process of Leptospira resuspension by rain, and Leptospira dynamics in rivers during, and after, flooding

 

 

Promoting organization

Cyrille Goarant

Responsable scientifique
Mail
cgoarant@pasteur.nc
Téléphone
277 531
Logo organisme
IPNC
Project start date
April 2018
Estimated end date of project
December 2020
Accordéon

AssurPluHyT

Leptospirosis is a zoonosis estimated to cause over one million cases and nearly 60,000 deaths worldwide each year, with an average annual incidence of 45 cases per 100,000 pop. in New Caledonia.

In rural and urban areas, in subtropical, tropical or temperate climate conditions, leptospirosis presents with symptoms which are difficult to distinguish from infections such as dengue fever or flu.

Transmission to humans occurs when Leptospira enter the human body via skin lesions or mucous membranes :

  • through direct contact with animals or their tissues, mainly rodents. Pathogenic Leptospira colonise the renal tubules of mammals and are excreted into the environment via urine;
  • In contaminated freshwater environments.

Leptospirosis outbreaks occur after heavy rainfall.

Rainwater leaches through the soil surface and carries Leptospira to water sources, thus leading to human exposure. Most cases of human infections are attributable to indirect exposure via surface water, soil and mud. Such exposure may be work-related, such as people working in water-irrigated rice or taro fields or banana plantations, or may be related to leisure activities or subsistence farming, e.g. swimming or freshwater, fishing, etc.

Outbreaks of leptospirosis tend to occur during periods of heavy rainfall, and seasonal peaks are noted. There is an uneven spatial distribution of cases in New Caledonia, with, however, the highest incidence recorded on the northern East Coast of the Main Island.

Mesures in situ de paramètres d’un sol à Touho.
In situ measurements of soil parameters in Touho.

Photo credit ME Soupé-Gilbert IPNC

Currently, there is a scarcity of data concerning:

  • the conditions for survival of pathogenic Leptospira in water and soil environments;
  • the resuspension of Leptospira during heavy rainfall;
  • freshwater contamination dynamics and the resulting health risk.

The ASSURPLUHYT project therefore involves collaborative work between microbiology, geochemistry, hydrology and hydro-geochemistry experts. Consequently, the project will be carried out in close collaboration with the University of New Caledonia ISEA laboratory and the Institute for Research and Development (IRD).

Targeting the Touho region, which presents a high incidence of leptospirosis, the project focus is the characterisation of physico-chemical conditions favouring the survival of pathogenic Leptospira in soils.

The impact of such physico-chemical conditions will then be tested in controlled laboratory conditions.

Based on the expertise developed to study mining-related materials transfer, the characterisation of Leptospira resuspension and transport dynamics during flooding will provide a better understanding of the infection risk linked to heavy rainfall, a risk recognised worldwide.

The project may well find evidence that this risk is related to hydrology, and such findings will allow an estimation of the risk timeframe after water levels fall.

By adopting a multidisciplinary approach, the impact of parameters such as vegetation and soil stability can be addressed, thereby providing additional data on the dispersion of Leptospira in the environment.

These findings will form the basis for a clearer understanding of leptospirosis infection risks, and ultimately the implementation of hydrology and soil properties-related infection risk mapping.

Thus, the ASSURPLUHYT project aims to

  • Accurately determine the physico-chemical composition

     - of soils;
     - of run-off water;
     - of Total Suspended Solids (TSS) when flooding occurs.

  • Quantify Leptospira in complex matrices (soil, water, TSS during flooding);
  • Determine optimal physico-chemical parameters for the environmental survival of pathogenic Leptospira
  • Determine the dynamics of Leptospira resuspension during the rise and fall of floodwaters so that health risks may be more accurately assessed.

 

The Institut Pasteur in New Caledonia (IPNC) UREL laboratory has already identified contaminated sites in Touho, the location for the field study.

Ascertaining, as part of this project, the physico-chemical properties of soils found in these sites – an historic and possible future source of cases of human infection with leptospirosis -, will lead to a more accurate characterisation of the soil as an environmental reservoir of pathogenic Leptospira. The technology required for the detection of viable Leptospira from environmental samples has been validated by the IPNC.

Experimental soil erosion plots already fitted with measurement devices will be used to:

  • Characterise the physical and chemical properties

      - of soils;
      - of run-off water, to obtain a clearer picture of how this compartment contributes to soil-related Leptospira dispersion subject to varying rainfall patterns.

Analyses will be made quarterly so possible seasonal variations can be assessed.

  • Determine the impact of environmental parameters on suspended solids and Leptospira numbers in run-off water, based on the presence of different vegetation covers representative of individual ecosystems on various erosion plots;
  • Characterise suspended solids and quantify Leptospira in order to determine the role of soil/river connectivity in Leptospira dispersion;

During various rainfall events, water samples will be taken from rivers fed by water from the watershed which also includes the experimental erosion plots.

Detailed analysis of suspended solids in these two fluid compartments (runoff waters and river waters) will elucidate the way(s) in which Leptospira are dispersed, directly in water or attached to the surface of suspended solids.

This research will draw on P. Genthon’s (IRD) expert knowledge in the field of hydrology, and on work using a comparable methodological approach undertaken at UNC (P. Gunkel-Grillon and C. Laporte-Magoni) and at the IRD (F. Juillot) as part of the CNRT projects (DMML and DYNAMINE), and the doctoral thesis by A. Boula (directed by Nazha Selmaoui-Folcher and co-supervised by P. Gunkel-Grillon and C. Laporte-Magoni).

AssurPluHyT

The workshop of the programm "Au fil de l'eau" took place on 17 and 18 September 2019, at the UNC.

Tuesday 18 September was dedicated to the intermediate results of the "Au fil de l'eau" program (whose presentation is available on the french's page of the project). This restitution day was an opportunity to exchange on the various projects that make up the program, between research professionals, actors from the public, private and associative sectors working on these themes

 

 

Partenaires associés

GOUTTE

In New Caledonia, water governance is overseen by a specific institutional organisation endowed with a regulatory framework which is incomplete and sometimes out of step with local customs and practices.
 

Les tensions su l'eau en NC

 

The institutional organisation varies depending on the land tenure status, customary land being excluded from the New Caledonia public waterways domain, in accordance with Article 44 of the 1999 Organic Law, as amended in 2009.

Tensions on customary land therefore arise in respect of “sacred” water, pollution, particularly from mining, and pricing and access to drinking water.
Several studies in New Caledonia have focused on improving knowledge of freshwater resources, in terms of both quantity and quality, but little research has been done on water-related know-how and customs or methods of water resource governance.

Thus, the aim of the GOUTTE project is to:

•    Gain an understanding of representations or protests linked to water in customary land, rooted in the bond between water and mankind, land, language and culture and the sacred;
•    Analyse the development of values, knowledge and customs relating to water on customary land in New Caledonia;
•    Analyse regulatory and legal frameworks, aiming to put divergences between international law and local practice into perspective;
•    Look at innovative rules of management and methods of governance, developed in collaboration with local stakeholders and based on representations, values and traditional uses, adopting an approach of integrated management of water resources throughout New Caledonia.

 

Promoting organization

Séverine Bouard

Responsable scientifique
Research team / laboratory

Equipe TerAU

Mail
bouard@iac.nc
Téléphone
477 616
Logo organisme
IAC
Project start date
January 2019
Estimated end date of project
December 2020
Accordéon

Building on a Pacific Fund project
The Goutte project has been developed to build on a Pacific Fund project undertaken between 2014 and 2016 and entitled “Fresh water supply and the land-water nexus in the Pacific: competing uses, complex regulations, conflictive political issues”.
This project was led by the Australian National University (ANU) and involved New Caledonia (IAC in association with the North Province), the Kiribati Islands, the Solomon Islands and Tonga.

The ANU project focused on water-related collaborative issues and aimed to
•    Promote “water-social science” research collaboration and networks in the Pacific;
•    Identify research themes with promising and inclusive reach and appeal throughout the Pacific.

The issue of water governance on customary land emerged as a key topic both for researchers and communities involved in the project (Bouard et al, 2017; Daniell et al, 2016; Bouteloup, 2015; Lejars et al, 2016).

2017, launch of exploratory research
In the wake of this initial project, IAC, CIRAD and IRD launched an exploratory study in 2017, focusing on the topic and funded by the Montpellier Institute of Water and the Environment (IM2E) in New Caledonia (Nekiriai, 2017; Lejars et al, 2017) in association with researchers from the “Eau-SHS” network set in place by the Pacific Fund project.

Indigenous peoples' rights of access to water - an issue frequently discussed in existing literature
The issue of water governance on customary land occupies a whole field of the existing literature on “indigenous peoples’ rights” of access to water, which often highlights the interconnections between political, land and environmental claims and water resource ownership claims made by indigenous peoples (see for example: Hidalgo et al, 2017; Boelens and Seeman 2016 as regards South America; Tripod, Trepied, 2011 & Trepied, 2004 as regards New Caledonia).

Another section of existing literature focuses on repercussions deriving from divergences in institutional systems regulating access to safe drinking water (Chambre des communes, 2005, Penn, 2016)  

A topic also addressed in the Pacific Region
In New Zealand; the sacred and symbolic nature of water is reflected in practical terms in innovative methods of water resource management (Jackson and Altman, 2009; Hsiao, 2012).
In the Pacific Region, while issues relating to water on customary lands have been identified, there has been little research focussing on the central issue at stake (Daniell et al, 2016).

Against this background, New Caledonia can serve as a model for the development of innovative modes of water governance which factor in local knowledge and practices (Bouard et al, 2017; Lejars et al, 2017).

 

GOUTTE is a multidisciplinary project. Water governance on customary lands involves several disciplines (law, water management, anthropology, geography...) and thus requires cooperation and discussion between researchers and key players in these fields.

Projet Goutte     The project is therefore structured around 5 major work packages spread over 3 years, with specific         contributors assigned to each package.
To ensure that diversity of practices, knowledge and languages is taken into account, research work will mainly be conducted in three common land areas: ideally, the North Province, the South Province and the Loyalty Islands Province.

The GOUTTE project aims to:

Improve knowledge of water-related know-how and practices on customary land, including perception of risks associated with water shortage or flooding;
Facilitate awareness raising and the sharing of new practices and management rules, including water saving and water pricing issues;
Support consolidation of the legal framework regulating water and aquatic environments, with a view to adapting it to reflect the legal fragmentation of rivers and groundwater;
Clarify the social feasibility of introducing new
•    hydraulic structures (e.g. dams)
•    Systems for:
o    management and sharing of water (e.g. river contracts)
o    water pricing

 

At New Caledonia level
The GOUTTE project should help to consolidate and broaden existing partnerships, by
•    setting up local workshops
•    joint training of a civic service volunteer (VSC)
•    joint work by researchers on common lands
•    Involving researchers from other disciplines and institutions like the ADCK and IANCP.

Moreover, the project will be carried out, wherever possible, in interaction with other research projects led by CRESICA, for the purposes of which knowledge of water-related practices and know-how could serve as complementary or supporting factors.

At community level
The GOUTTE project will be carried out in coordination with research on water policy in New Caledonia led by MISE. Debates and discussions on program progress and findings will be scheduled in conjunction with the DGRAC/DAVAR/START, the Customary Senate/North Province/South Province/Loyalty Islands Province.

At Pacific Region level
Funding from bodies such as the Pacific Fund or IM2E could strengthen existing collaborations, particularly with the ANU in Australia, with Vanuatu, Tonga and the Kiribati Islands.

 

The GOUTTE project mobilises tools and methodologies drawn from the various disciplines within the project scope: water management, geography, anthropology, linguistics.

Each social science discipline will use its own methodological tools, such as
•    Direct or participant observation
•    Historic data from analysis of public and/or private archives
•    Conducting open and semi-structured interviews
•    Survey analysis, regulatory frameworks
•    Studies, spatial data
•    Children's drawings...
 

Goutte
Photo credit: Catherine Sabinot

Interview with a farmer about his water management practices

 

This will involve

•    Listening to elders talking about the changes they have observed and experienced
•    Asking young people about their knowledge, practices and representations/protests and contrasting them with those of older generations

Given the diverse range of disciplines and methodologies, the GOUTTE project plans to make common and shared lands are central focus for research work. The choice of lands, still to be defined, will be designed to ensure that case studies in the North Province, South Province and Loyalty Islands Province are covered.

Having researchers work on common lands will promote

•    Scientific discussion between researchers from different disciplines
•    Discussion with local stakeholders.

Work groups and project monitoring involving the DGRAC and community water services will also be put in place.
Finally, depending on available resources, an international seminar addressing the issue of water on customary lands could be scheduled.

The workshop of the programm "Au fil de l'eau" took place on 17 and 18 September 2019, at the UNC.

Tuesday 18 September was dedicated to the intermediate results of the "Au fil de l'eau" program (whose presentation is available on the french's page of the project). This restitution day was an opportunity to exchange on the various projects that make up the program, between research professionals, actors from the public, private and associative sectors working on these themes.

 

 

Partenaires associés

"Along the River" program

The “Along the River” program comprises research and innovation projects focussing on the integrated management of water, its uses and its governance, and involves close cooperation between CRESICA members, local authorities and the economic sphere. The program is funded by the 2017-2021 State-Joint Local Authority Development Contract.

Doctorat

CRESICA implements a policy for the training of young researchers. Most are enrolled at the Ecole Doctorale du Pacifique (Pacific PhD School), and some PhD students working within CRESICA member institutions are enrolled at French PhD schools.

Master’s Degree

Environmental management is a major issue for New Caledonia, as both one of the world’s key biodiversity hotspots and the world’s fourth largest producer of mined nickel. Exploitation of this vast natural resource and the related environmental repercussions, together with the management, conservation and development of New Caledonia’s outstanding biodiversity are areas of key priority for the country.

Des molécules naturelles pour stimuler les défenses antimicrobiennes humaines (French only)

Face à la menace récurrente de l’antibiorésistance, de nouvelles stratégies thérapeutiques sont...

Système Terre et Big data : lancement de l'infrastructure européenne EPOS (French only)

L’infrastructure européenne EPOS, dont le BRGM est partie prenante, sera officiellement lancée le 7...

Les coraux de Moorea font de la résistance (French only)

Les spécialistes d’écologie marine s’intéressent à la santé des récifs coralliens, mise à rude...

Journée mondiale du diabète (French only)

Soutenue par l’OMS (Organisation mondiale pour la santé), la Journée mondiale du diabète est...

Des membres du CRESICA sur Radio Rythme Bleu (French only)

Le 16 octobre 2018, trois membres du CRESICA participaient au Magazine Citoyen de RRB, le rendez...

Legal Notice

Publisher
Director of publication: CRESICA's Animation and Project Engineering Unit

Director: SCSI
Hosting: UNC
Photo credit: CRESICA

Intellectual property - All rights reserved

Sortie du livre de l’UNC sur l’avenir institutionnel de la Nouvelle-Calédonie (French only)

À l’occasion de la Nuit du droit organisée à l’université jeudi 4 octobre 2018, l’UNC met en ligne...

PEMPOM

The PEMPOM project, emerging pollutants, organic pollutants and heavy metals, is a ground-breaking research project in New Caledonia.
While organic and metal pollutants have been studied for a long time in most temperate marine areas, research focusing on coral reefs is much more recent and remains relatively fragmented overall. Moreover, it would appear that, to date, so-called emerging pollutants have never been studied in a reef and lagoon environment.
Contamination caused by these pollutants, possibly introduced into New Caledonia’s coral ecosystems through food webs, can be directly linked to anthropogenic activities (pesticides used in agriculture, soil erosion linked to agricultural practices and deforestation, mining operations, urban activities, in the case of emerging pollutants), but can also have a natural origin as regards some metal contaminants (dissolution of rocks, etc.).

The PEMPOM project therefore aims to:
•    attempt to identify the major sources of emerging, organic and heavy metals pollutants
•    assess their fate and effects in New Caledonia’s reef and lagoon ecosystems (amplification -or not- in food chains)
•    assess concentrations in various compartments in food chains (algae, invertebrates, fish) and the contamination of local populations consuming fish and seafood
•    suggest directions for further research, such as, for example, expanding research into physiological processes

 

Promoting organization

Yves Letourneur

Responsable scientifique
Research team / laboratory

ISEA

Mail
yves.letourneur@unc.nc
Téléphone
290 385
Logo organisme
UNC
Album photo
Persto plaga valetudo vicis.
Ad blandit proprius sagaciter si.
Anse Vata
Project start date
July 2018
Estimated end date of project
July 2021
Accordéon

To date, there has been no research into emerging pollutants in the tropics; they have only been studied in temperate environments in highly developed countries. The focus has so far been mainly on freshwater ecosystems.
Although contamination due to emerging pollutants has not been of crucial interest in recent years, coral ecosystems are subject to increasing anthropogenic pressures, and it is therefore conceivable that marine environments could be affected by this type of pollutant.
Natural or mining-related sedimentation acts as the carrier of a whole range of heavy metals (Ni, Co, Cr, Mn, etc.) and/or pesticides, which could impact marine ecosystems and fish caught by traditional fishing methods.
The urban development of “Greater Noumea” also means that wastewater requires increased attention and that wastewater evacuation into the receiving environment (such as coral ecosystems) must be assessed.
Population growth also drives agricultural development to meet rising demand for food. Many pesticides are used, sometimes in poorly controlled or uncontrolled quantities. This raises the question of their fate and effects in the receiving environments, including fish and sea food consumed by the population.

 

The marine environment is the ultimate repository of freshwater sources throughout New Caledonia, be they underground (percolation, infiltration, etc.) or on the surface (rivers, runoff), or derived from urban waste (drains, discharge from wastewater treatment plants, etc.).
As a consequence, reef and lagoon environments are directly affected by such freshwater inflows and subject to variability in quantitative and qualitative, and also spatial and temporal terms.
The species inhabiting these ecosystems are also liable to ingest and absorb into their tissues all or part of the elements carried by water bodies, either directly (food) or indirectly (phenomena of dissemination or osmotic transport, etc.)

The PEMPOM project aims to analyse:
•    the sources of emerging, organic and heavy metals pollutants;
•    concentrations in various biological compartments in the coral ecosystem, and in humans who consume fish and seafood.

To this end, various research sites have been identified, such as freshwater “vectors”, including wastewater treatment plants (traditional activated sludge process and microfiltration membrane process), the lagoon and estuaries receiving water from septic tanks and household-level sanitation systems, such as the La Foa river, the area of corals opposite the estuaries.

 

PEMPOM
La Foa river area mapping @Cart'eau Georep

Given the total lack of prior knowledge as regards emerging pollutants in the tropics, during a preliminary phase, research will be carried out on only a few biological compartments located in the immediate vicinity of these receiving areas, to test for possible contamination of the coral ecosystem (e.g. algal turfs, territorial herbivorous fish).

The PEMPOM project will carry out targeted sampling on key species constituting “food chains”, aiming at a spatial vision in order to:
•    understand how contaminants (pesticides, metals, emerging pollutants) become absorbed (or not) into these key species;
•    assess health implications in the event of high concentrations of pollutants in a few iconic species of commercial interest, which are representative of the dietary habits of New Caledonians;
•    assess, for the first time in New Caledonia:
o    whether so-called emerging pollutants have a significant impact on the reef environment and whether there are grounds for suspecting an accumulation in food webs.
o    the potential contamination sensitivity of seabirds (exclusively fish-eating), species of major heritage significance (biomonitoring, etc.)
•    study various sectors characterised by dissimilar potential pollutant inputs into coral systems (reefs not impacted by humans, reefs subject to agricultural inputs, reefs subject to inputs from treatment plants).

This project is therefore designed to provide answers to key questions about contamination rates and the diversity of compartments studied, with a view to assessing how contaminants are absorbed into food webs ending with focal species.

Spinoffs from the PEMPOM project could:
•    Enable findings from several Pacific islands to be transposed, at least in general terms. The project is already being conducted in close collaboration with similar projects in Wallis, Futuna, Vanuatu and Fiji;
•    provide clarification on other aspects of basic research which will focus, significantly on physiological processes;
•    have implications in terms of:
o    management and protection of sensitive species (protected areas, raising awareness and regulatory framework, etc.)
o    management of fisheries resources (traditional fishing, etc.) and development of regulations targeting fish, seafood and public health (contaminant levels and potential health risks, etc.)
o    management of natural areas and species.

 

The PEMPOM project aims to promote collaborative work between key CRESICA consortium partners who are active in this field, i.e. the UNC, the CHT and the IRD, together with universities in France (La Rochelle and Aix-Marseille) and abroad (New Zealand), while involving Calédonienne des Eaux water company, a key player in the local economy, and also New Caledonia’s provincial government authorities.
This method of collaborative work aims to bring in partner-colleagues who have done work and/or are currently working in this area, with a view to optimising the effectiveness of work undertaken as part of the PEMPOM research project.
Furthermore, the involvement of colleagues from Noumea CHT, in close contact with medical circles, will mean that the project, according to the results achieved, could set a clear benchmark in terms of social significance.
Research work will be rooted in an approach based on dynamic predictive mathematical models and multidimensional data analysis, which will take into account the spatial variability of contaminant levels for several compartments in the food web, thereby enabling the assessment and prediction of potential contaminant accumulation phenomena.
Theoretical and digital simulation studies will also be carried out on the properties of models and estimators.
The project will also build on research recently conducted on issues directly affecting New Caledonia (thesis by M.Briand, master 2 internships by P.Fey and J.Liétar).

 

The workshop of the programm "Au fil de l'eau" took place on 17 and 18 September 2019, at the UNC.

Tuesday 18 September was dedicated to the intermediate results of the "Au fil de l'eau" program (whose presentation is available on the french's page of the project). This restitution day was an opportunity to exchange on the various projects that make up the program, between research professionals, actors from the public, private and associative sectors working on these themes.

 

La fête de la science à Ouvéa (French only)

Une équipe de l'Ifremer a fait le déplacement dans les îles Loyauté pour l'ouverture de la fête de...

Soutenance de thèse de Martin Thibault (French only)

Martin THIBAULT soutiendra sa thèse intitulée : " The red vented-bulbul (Pycnonotus cafer): invasion...

Marc Jouan, Directeur international de l'Institut Pasteur, en Nouvelle-Calédonie (French only)

Le second comité de coordination de l’Institut Pasteur de Nouvelle-Calédonie s’est déroulé le 9...

Roman Thibeaux à l'assaut de l'armure bactérienne (French only)

Atteindre les bactéries responsables de la leptospirose en s’attaquant au “bouclier” qu’elles...

Des sénateurs à l’UNC pour découvrir la recherche en Nouvelle-Calédonie (French only)

Mardi 22 mai, l’UNC a reçu une délégation de sénateurs venus de Paris pour une visite sur le...