LIttoral ENvironnement et Sociétés (LIENSs) - UMR 7266

ECOP - Changes in Costs and Practices

Thierry Guyot — 2026-10-22T13:19:39Z

ECOP : Coastal Evolution and Practices (Évolution des CÔtes et des Pratiques) comprises two research units :

The Observatory of Tourism and Leisure Practices (head : L. Vacher)
Coastal Evolution (head : E. Chaumillon)

OBSERVATORY OF TOURISM AND LEISURE PRACTICES

(HEAD : L. VACHER)

Participants : D. Amiaud, L. Beretti, C. Blondy, V. Duvat-Magnan, L. Marrou, C. Parrain, F. Pouget, L. Vacher, D. Vye

Established in 2007, the Observatory of Tourism and Leisure Practices aims to generate knowledge about coastal and maritime activities to support decision-making. Its work focuses on two areas where Marine Natural Parks are being established : the Pertuis archipelago (the islands of Ré and Oléron) on France's Atlantic coast, and the French overseas department of Mayotte.

Its objectives are, firstly, to characterize, understand and better define these practices and how they evolve (fundamental research) and, secondly, to provide local and regional authorities with information to support decision-making on issues relating to environmental protection, urban development, land-use planning and coastal management.

The data collected are made available to coastal stakeholders and are intended to feed into the GIS services of partner local authorities, including the La Rochelle urban community, the municipalities of the islands of Ré and Oléron, and the Marennes-Oléron regional authority.

The Observatory's work contributes to territorial assessments at a particularly strategic time :

On Ré : ongoing revision of the territorial coherence scheme (SCOT) ;
On Oléron : the integrated coastal zone management policy is entering its operational phase through the Oléron Qualité Littoral initiative (Beach Plan) ;
At the level of the La Rochelle urban community (CDA) : completion of the SCOT ;
At regional level and over the longer term : establishment, in April 2009, of the study mission for the Marine Natural Park of the Gironde Estuary and the Pertuis Sea.

The Observatory focuses on urban sprawl, mobility and residential patterns, tourism and leisure practices, beach quality, and land-based and maritime territoriality.

[Observatory website :] Observatory of Tourism and Leisure Practices

COASTAL EVOLUTION

(HEAD : E. CHAUMILLON)

This research examines coastal defence strategies, including the technical solutions implemented at municipal level, how these solutions evolve, comparisons between the strategies of neighbouring municipalities, and the relationships between the extent of coastal retreat and the associated stakes, on the one hand, and public intervention, on the other. This approach will make it possible to assess the consistency and progress of risk management policies.

Correlation between coastal morphological changes and the regional wave climate

(Head : Eric Chaumillon – in collaboration with the Charente-Maritime Departmental Council)

Predictions of significant wave height, in metres, shown at three-hour intervals (blue curve) and averaged monthly (red curve) from January 1998 to April 2008 off the island of Oléron (2.5°W, 46°N), using the WaveWatch III model (Tolman, 1991). In addition to the clear seasonal variations, this graph highlights the strong interannual variability in the wave climate along the Charente coastline.

Beach-perpendicular topographic profiles measured on the island of Oléron (Saint-Trojan, Grande Plage) between September 1999 and September 2007. These profiles illustrate erosion rates averaging between 5 and 24 m per year.

Compilation of a database on the Charente coastline : HISTOLITTO (head : F. Pouget)

HISTOLITTO is a geohistorical database documenting changes in the coastline and land use over time. It currently contains more than 800 maps and plans spanning five centuries of history, 100 of which have already been georeferenced. It also includes archaeological data (the PATRIARCHE database), elevation data (the national BD TOPO database acquired, new radar digital terrain models with a 5 m grid spacing from NEXTMAP currently being tested, and LiDAR data with a 1 m grid spacing).

The database also incorporates reference datasets, including those produced by the French National Institute of Geographic and Forest Information (IGN : BD TOPO, Scan 25), the French Geological Survey (BRGM : maps) and the French Hydrographic and Oceanographic Service (SHOM : bathymetry).

Following the data collection work initiated in 2008, the year 2009 made it possible to :

(1) Integrate additional data into the database ;

(2) Organize and structure the data to enable the production of analyses ;

(3) Organize meetings to present the database to its users and potential contributors.

In 2010, a tool enabling researchers to access these data was scheduled to be developed.

OBIONE - Pertuis Charentais Flora and Fauna Biodiversity Observatory

Thierry Guyot — 2026-10-22T13:15:38Z

L'Observatoire de la Biodiversité Faune-Flore des Pertuis charentais (OBIONE) a pour objectif de réaliser un bilan de la biodiversité des invertébrés benthiques et des macroalgues à l'échelle géographique des Pertuis charentais et de contribuer à observer leurs évolutions.

OBIONE s'appuie sur un bilan réactualisé dans les années 2000 des connaissances sur la faune des invertébrés et la flore des macroalgues marines des Pertuis charentais, et plus largement sur les habitats littoraux, côtiers et estuariens de la Mer des Pertuis charentais. Les observations du LIENSs sont réalisées en collaboration avec :

Le réseau BenthOBS ou réseau d'observation de la macrofaune benthique inclus dans l'infrastructure de recherche littorale et côtière (ILICO). Le BenthOBS a en charge d'établir d'une part des inventaires faunistiques à proximités des stations marines et, d'autre part, une base de données recensant l'ensemble des données de la macrofaune benthique de la façade maritime française, principalement métropolitaine, en vue de son exploitation scientifique ;
Le réseau d'observation « Littoral, limicoles et macrofaune benthique » des Réserves Naturelles de France RNF ;
L'Office français de la biodiversité OFB à travers le projet CARTHAM de 2012 de cartographie des habitats marins littoraux et côtiers qui a permis grâce à des stratégies coordonnées d'acquisition de connaissances (sonar, satellite, vérité terrain, prélèvements ponctuels) de cartographier les habitats marins selon une typologie commune à l'échelle européenne (EUNIS).

Les activités d'observation se traduisent par :

La réalisation de suivis DCE/DCSMM sur trois indicateurs de la qualité écologique que sont les invertébrés de substrats meubles, les herbiers de Zostera noltei et les macroalgues de substrat rocheux et meubles intertidaux. Les stations de surveillance sont localisées dans le Pertuis breton, le Pertuis d'Antioche, la baie de Marennes-Oléron et les estuaires du Lay, Charente, Seudre et Gironde. Ces suivis sont coordonnés à l'échelle nationale par ifremer et le MNHN Concarneau. Ils se font en collaboration avec Cohabys de La Rochelle pour les indicateurs "faune des invertébrés et herbier" et avec l'association OBIOS-Objectifs Biodiversités de Pont-l'Abbé-d'Arnoult pour l'indicateur "macroalgues intertidales".
La mise en place d'un suivi à long terme de la macrofaune benthique sur une station de référence située dans le Pertuis d'Antioche à l'écart des influences estuariennes et anthropiques. Il est mené en parallèle d'un suivi des paramètres physico-chimiques et phytoplanctoniques de la colonne d'eau coordonné à l'échelle Manche-Atlantique dans le cadre du Service d'Observation en Milieu Littoral SOMLIT et du Réseau d'observation du phytoplancton PHYTOBS.
La réalisation d'un suivi annuel des habitats benthique des quatre réserves naturelles des Pertuis Charentais : Baie de l'Aiguillon, Lilleau des Niges, Yves et Moëze-Oléron (Collaboration OBIONE/RNF/LPO/ONCFS).
La détection et la prise en compte d'informations nouvelles concernant des espèces (faune et flore) non encore observées dans les Pertuis Charentais, en particulier les espèces introduites et parfois invasives. Ces informations proviennent des suivis, des travaux de thèse, des projets de recherche, des collaborations réalisées dans le laboratoire LIENSs ainsi que des signalisations émanant d'usagers du domaine public maritime.

Les sites DCE/DCSMM sont distribués comme suit :

En eaux côtières :
- Pour les macroalgues, un site sur l'île de Ré au Grouin et un site sur l'île d'Oléron au Sabia.
  - Un survol drone au Sabia a permis au printemps 2021 de noter, en comparaison du suivi antérieur de 2018, la disparition de la ceinture d'Ascophyllum nodosum - Fucus vesiculosus d'une grande partie du médiolittoral moyen..
  - Un survol drone au Grouin a permis à l'automne 2021 d'établir une cartographie des habitats selon la typologie EUNIS et de caractériser l'évolution temporelle de la richesse spécifique des ceintures algales pour la période 2007-2019.
- Pour les invertébrés, trois site dans le Pertuis breton et trois sites dans le Pertuis d'Antioche et baie de Marennes-Oléron.
- Pour les herbiers de Zostera noltei, deux sites sur l'île de Ré, trois sites sur l'île d'Oléron et un site à Bonne Anse dans l'estuaire de la Gironde.
  
  Carte de localisation des sites d'observation sur herbier (cliquer pour agrandir)
  
  Sauriau P.-G.
En eaux de transition :
- Pour les macroalgues, un site rocheux et un site sur vase dans chacun des estuaires de la Charente et de la Gironde.
- Pour les invertébrés, trois sites dans l'Anse de l'Aiguillon, cinq sites dans l'estuaire de la Charente et trois sites dans l'estuaire de la Seudre.

Publications

Hummel H., Van Avesaath P., Wijnhoven S., Kleine-Schaars L., Degraer S., Kerckhof F., Bojanic N., Skejic S., Vidjak O., Rousou M., Orav-Kotta H., Kotta J., Jourde J., Pedrotti M.L., Leclerc J.-C., Simon N., Rigaut-Jalabert F., Bachelet G., Lavesque N., Arvanitidis C., Pavloudi C., Faulwetter S., Crowe T., Coughlan J., Benedetti-Cecchi L., Dal Bello M., Magni P., Como S., Coppa S., Ikauniece A., Ruginis T., Jankowska E., Weslawski J.M., Warzocha J., Gromisz S., Witalis B., Silva T., Ribeiro P., Fernandes De Matos V.K., Sousa-Pinto I., Veiga P., Troncoso J., Guinda X., Juanes De La Pena J.A., Puente A., Espinosa F., Pérez-Ruzafa A., Frost M., Mcneill C.L., Peleg O., Rilov G., 2016. ‘Geographic patterns of biodiversity in European coastal marine benthos', Journal of the Marine Biological Association of the United Kingdom, , pp. 1–17. doi : 10.1017/S0025315416001119.
Le Garrec, V., Grall, J., Chevalier, C., Guyonnet, B., Jourde, J., Lavesque, N., Bonifácio, P. and Blake, J.A., 2016. ‘Chaetozone corona (Polychaeta, Cirratulidae) in the Bay of Biscay : a new alien species for the North-east Atlantic waters ?', Journal of the Marine Biological Association of the United Kingdom, , pp. 1–13. doi : 10.1017/S0025315416000540.
Spilmont N., Hachet A., Faasse M.A., Jourde J., Luczak C., Seuront L., Rolet C., 2016. First records of Ptilohyale littoralis (Amphipoda : Hyalidae) and Boccardia proboscidea (Polychaeta : Spionidae) from the coast of the English Channel : habitat use and coexistence with other species. Marine Biodiversity 1–11. doi:10.1007/s12526-016-0557-3
Drumm D.T., Jourde J., Bocher P., 2015. A new species of the genus Monokalliapseudes (Crustacea : Tanaidacea : Kalliapseudidae) from French Guiana. Proceedings of the Biological Society of Washington 128, 86–97. doi:10.2988/0006-324X-128.1.86
Jourde J., Sampaio L., Barnich R., Bonifácio P., Labrune C., Quintino V., Sauriau P.-G., 2014. ‘Malmgrenia louiseae sp. nov., a new scale worm species (Polychaeta : Polynoidae) from southern Europe with a key to European Malmgrenia species', Journal of the Marine Biological Association of the United Kingdom, 95(5), pp. 947–952. doi : 10.1017/S0025315414001878
Jourde J., Sauriau P.-G., Guenneteau S., Caillot E., 2013. First record of Grandidierella japonica Stephensen, 1938 (Amphipoda : Aoridae) from mainland Europe. BioInvasion Records 2(1) : 51-55 (open access)
Sauriau P.-G., Curti C., Jourde J., Aubert F., Cajeri P., Lavesque N., Dubois S., Lepareur F., Gouesbier C., Sauriau F., Sauriau M., Latry L., Leguay D., Robert S., Pineau P., Geairon P., 2012. Le maerl algues corallinacées marines dans les Pertuis Charentais. Annales de la Société de Sciences Naturelles de Charente-Maritime 10(3) : 281-300

Travaux associés

présentation du projet EMBOS

OBIONE en bref :

Date de création : 01/01/2012
Coordonnées : 2 rue Olympe de Gouges, 17000 La Rochelle

Responsables :
– Pierre-Guy Sauriau, Chargé de Recherche CNRS
– Jérôme Jourde, Ingénieur d'Étude CNRS

Objectif :
Suivi de la biodiversité des invertébrés et macroalgues marines dans la Mer des Pertuis charentais

Compétences :
– Analyse faunistique d'échantillons d'invertébrés marins
– Expertise écologique du bon état écologique

Contact
Sauriau P.-G. - Jourde J.
Email : pierre-guy.sauriau*at*univ-lr.fr
Email : jerome.jourde*at*univ-lr.fr

PHYTOBS - Phytoplankton Observation Network

Thierry Guyot — 2026-10-22T13:12:45Z

National observation network website : IR-ILICO

National observation network website : CNRS-INSU

PHYTOBS :

The phytoplankton observation network (PHYTOBS) is based on a network of 26 sites along the English Channel, Atlantic and Mediterranean coasts. These sites conduct long-term observations of marine and lagoon phytoplankton, together with measurements of their associated hydrological conditions, at fortnightly intervals.

The PHYTOBS National Observation Service (SNO) originated from two monitoring networks : REPHY (the Phytoplankton and Phycotoxin Observation and Monitoring Network), established by Ifremer in 1984, and SOMLIT (the Coastal Environment Observation Service), established by the CNRS in 1995.

PHYTOBS monitoring follows the strategy defined by SOMLIT : surface water sampling at high tide (at sites subject to tidal influence), every 15 days. In addition to phytoplankton sampling, 11 SOMLIT parameters are measured : temperature, salinity, dissolved oxygen, nitrate, nitrite, ammonium, phosphate, dissolved silica, suspended matter, chlorophyll a and suspended solids. All observations and analyses are carried out under a quality management framework.

Objectives of PHYTOBS :

Analyse the responses of phytoplankton communities to environmental changes ;
Assess the quality of coastal environments using indicators ;
Define ecological niches ;
Detect changes in phenology ;
Promote synergies within the scientific community, strengthen expertise and disseminate knowledge as part of the services provided by the National Observation Service.

At the national level, PHYTOBS is coordinated by Maud Lemoine (Ifremer Nantes) and Pascal Claquin (UMR BOREA, University of Caen).

PHYTOBS in La Rochelle :

Since 2012, the LIENSs laboratory has been sampling one station every 15 days for PHYTOBS in the Pertuis d'Antioche, where the SOMLIT station is located.

Samples are collected using a Niskin bottle aboard L'Estran, the research vessel operated by La Rochelle University (L'Estran).
Lugol-preserved samples are examined and marine phytoplankton are counted under an inverted microscope using sedimentation chambers.

PHYTOBS team at LIENSs

[Scientific coordinator]

Christine Dupuy, La Rochelle University

Pierre-Guy Sauriau, CNRS (until 2023)

[SOMLIT technical coordinator]

Philippe Pineau, CNRS

[PHYTOBS technical coordinator]

Claire Emery, CNRS

[L'ESTRAN vessel operator]

Yves Brizard, La Rochelle University

[Taxonomic analysis coordinator]

Beatrix Beker, private company (since 2018)

Christophe Arnaud, CNRS (until 2018)

Last updated : November 2022]

BENTHOBS - Benthic Macrofauna Monitoring Network

Thierry Guyot — 2026-10-22T12:02:19Z

National observation network website : IR-ILICO
BenthOBS :

The benthic macrofauna observation network (BenthOBS) was established in 2019. It is a National Observation Service (SNO) currently in the “incubation” phase and is part of the Coastal and Marine Research Infrastructure IR-ILICO.

BenthOBS is a macrozoobenthos observation network that brings together the human resources, technical facilities and expertise of 12 partners from universities, the CNRS, Ifremer and the French National Museum of Natural History (MNHN).

In a context of global change affecting all the world's oceans, medium- and long-term time series make it possible to identify ongoing changes in benthic communities and improve our understanding of them, particularly in coastal environments. These changes affect species diversity within communities and the functioning of marine ecosystems.

The objectives of BenthOBS are to :

Understand the temporal trajectories of benthic macrofauna communities and characterize their functional dynamics ;
Compare BenthOBS data with existing macrozoobenthos data from other observatories (the ILICO Benthos database) and spatiotemporal monitoring programmes (WFD, MSFD) ;
Combine BenthOBS data with data from other National Observation Services monitoring water-column dynamics (COAST-HF, SOMLIT) and pelagic communities (SOMLIT, PHYTOBS) ;
More broadly, in a context of well-documented terrestrial biodiversity loss, acquire taxonomic and ecological knowledge of coastal marine species in mainland France, including their numbers, identity and dynamics.

At the national level, BenthOBS is hosted by the Laboratory of Oceanology and Geosciences (LOG, Joint Research Unit UMR 8187). The national coordinators are Vincent Bouchet (LOG, University of Lille, Université du Littoral Côte d'Opale, CNRS) and Nicolas Desroy (LER-CRESCO, Ifremer-MNHN).

BenthOBS in La Rochelle :

The LIENSs laboratory samples three stations twice a year : in early spring (March–April) and at the end of summer (September–October).

The stations are located at Boyardville in Marennes-Oléron Bay, at Pointe d'Arçay in the Pertuis Breton, and in the Pertuis d'Antioche (Antioche / SOMLIT / PHYTOBS). The data collected cover benthic macrofauna species richness, sediment grain size, sediment organic matter content and sediment CHN composition (carbon, hydrogen and nitrogen).
Samples are collected using a Van Veen or Smith-McIntyre grab aboard L'Estran, the research vessel operated by La Rochelle University (L'Estran).

BenthOBS team at LIENSs

Jérôme Jourde, CNRS Research Engineer : [Scientific coordinator]

Philippe Pineau, CNRS Research Engineer

Fabien Aubert, COHABYS ADERA Research Engineer

Last updated : February 2021]

DYNALIT - Coastal and Shoreline Dynamics

Thierry Guyot — 2026-10-22T11:57:58Z

Observation Service Website

SOMLIT : Coastal Environment Observation Service

Thierry Guyot — 2026-10-22T11:48:44Z

National Observation Service website
SOMLIT :

The Coastal Environment Observation Service (SOMLIT) is a National Observation Service (SNO) accredited by CNRS-INSU since 1996. Since 2016, it has been one of the basic networks of the Coastal and Marine Research Infrastructure (IR-ILICO).

Today, SOMLIT brings together 10 French coastal stations and marine laboratories along the English Channel, Atlantic and Mediterranean coasts, from Wimereux to Marseille via Brest. All SOMLIT teams follow common, standardized protocols.

SOMLIT aims to monitor changes in the marine environment over the medium and long term in order to understand how marine ecosystems respond to natural forcing and human-induced pressures through the study of multi-parameter time series.

SOMLIT observations cover marine hydroclimate, chemistry, biogeochemistry and the biology of the water column.

The common protocols require all participating teams to carry out the following :

Sampling at subsurface depth at high tide (± 1 hour), every 15 days ;
A surface-to-bottom profile using a multiparameter probe ;
Analysis of a set of 16 parameters ;
Implementation of a quality management approach in accordance with the NF EN ISO/IEC 17025 standard ;
Annual intercomparison exercises between CNRS and university laboratories, as well as participation in Ifremer interlaboratory proficiency tests.

SOMLIT makes all the results obtained available to national and international research communities through the SOMLIT national website.

SOMLIT in La Rochelle :

The LIENSs laboratory joined the SOMLIT network in 2012, following an initial implementation phase that began in June 2011.

The site is located in the Pertuis d'Antioche (between the islands of Ré and Oléron), 5 nautical miles from the port of Chef de Baie (La Rochelle), at a depth of 40 metres (blue dot on the map).

The site lies outside the areas affected by inputs from small rivers (the Lay, Sèvre and Charente) and away from major human activities (marine aquaculture, coastal fishing and dredging). It remains predominantly under oceanic influence, although its winter hydrological conditions are affected by the plumes of the Gironde and Loire rivers.

The site complements the hydrological monitoring stations of the pre-existing REPHY and WFD (Water Framework Directive) networks (yellow dots on the map), some of which are located near marine aquaculture areas (oyster and mussel farming).

Sampling is carried out at high tide, at a tidal coefficient of 70 (± 10), aboard the research vessel L'ESTRAN operated by the University of La Rochelle.

Seawater samples are collected using a Niskin bottle. Surface-to-bottom profiles are obtained using a Sea-Bird SBE 19plus multiparameter probe, while qualitative phytoplankton samples are collected using a phytoplankton net with a mesh size of 10 µm.

The seawater collected in the Niskin bottle is then transferred into containers selected for each parameter (O₂, pH, nutrients, pico- and nanoplankton), and the appropriate fixatives are added.

[Organizational chart :]

Contacts :

[Scientific coordinator :] Hélène Agogué, CNRS Research Scientist, tel. : 05 46 50 76 50

Email : helene.agogue@univ-lr.fr

[Quality manager :] Philippe Pineau, CNRS Engineer, tel. : 05 46 50 76 60

Email : philippe.pineau@univ-lr.fr

Last updated : January 2024]

SONEL

Thierry Guyot — 2026-10-22T10:48:48Z

[Observatory website :] Sea Level Observation Service

SONEL's main objective is to collect and disseminate coastal sea-level observations recorded by tide gauges, ensuring the highest possible metrological quality. These data provide researchers with the information they need to address the questions currently being raised about changes affecting the various components of sea level : Is mean sea level rising ? Where ? How ? Why ? Are storm surges more frequent today ? And so on.

Answering these questions depends on the acquisition of long time series of sea-level records. Synergies between tide-gauge measurements and other measurement techniques are also key to interpreting these observations, particularly precise space-based positioning techniques (GPS, DORIS, etc.), which make it possible to verify the geodetic stability of the ground on which tide gauges are installed.

A video overview of SONEL Observatory activities :

L'île aux chercheurs : Measuring tides on Île d'Aix