Clément Lambert

• PhD
• Enseignant-chercheur (MCF) / Associate Professor at Université Bretagne Sud Vannes

The Bay of Brest (BB, NW France) is a semi-enclosed basin of 180 km² subject to macro-tidal dynamics and to the fluvial influences of the rivers Aulne and Elorn, which combined drain watersheds of 2600 km². This coastal environment is subject to natural climate oscillations overlaid on the long-term landscape transformations inherited from the post...

The Bay of Brest (BB) is a shallow estuarine environment in NW France. This semi-enclosed basin of 180 km² is subject to multiple hydrodynamic factors including the dual influence of oceanic currents and fluvial discharges (Aulne and Elorn main rivers) and resulting in complex hydro-climatic and hydro-sedimentary processes. This study investigates...

Harmful algal blooms occur when toxin-producing microalgae grow excessively in coastal waters. In France, surveys are done by Ifremer since 1987 through two networks, REPHY and REPHYTOX. Temporal series of toxic microalgae populations are necessary to better assess the dynamics of these recurring seasonal phenomena. Unfortunately, only about 40 yea...

Harmful algal blooms occur when toxin-producing algae grow excessively in coastal waters. In France, surveys are done by the Ifremer since 1987 through two networks, REPHY and REPHYTOX. Temporal series of toxic algae population are necessary to better assess the dynamics of change of these recurring seasonal phenomena. Unfortunately, only about 40...

Les archives sédimentaires holocènes, prélevées en contexte de plateforme, offrent une vision pluri-séculaire permettant de reconstruire l’impact des variations climatiques sur les environnements de la marge métropolitaine atlantique en s’éloignant de la période Anthropocène. C’est particulièrement le cas du dernier millénaire avec la succession de...

New findings acquired in Armorican shelf (core MD08-3204 CQ: Bay of Quiberon and core VK03-58bis: South Glénan islands) depict Holocene paleoenvironmental changes since 10 ka BP through a multi-proxy dataset including sedimentological and palynological data. First, grain-size analyses and AMS-¹⁴C dates show a common sedimentary history for both stu...

Dinoflagellate cyst assemblages from 15 modern surface sediment samples of the Bay of Quiberon (Southern Brittany shelf) have been examined to assess their potential as marine bio-indicators for paleoenvironmental reconstructions in a shallow coastal environment. Some discrepancies are noted in the distribution of dinocyst taxa in the study area, a...

The major climatic oscillations during the Quaternary Period significantly influenced the evolution and distribution of ancient and modern coastal systems. Here we investigate the morphology and sedimentary infilling of submerged Late Quaternary incised valleys along the northern coast of Java Island (Indonesia) using high-resolution geophysical, s...

The Bay of Brest (BB) is a mixed, tide-dominated estuarine system. The shore terraces of this bay are occupied by modern free-living (calcareous) coralline algae locally termed “maerl”, organized in bed-like morphologies (rhodolith deposits). Cores retrieved from around the bay reveal fossilized primitive maerl beds of Holocene age, interbedded in...

To evaluate the stability and resilience1 of coastal ecosystem communities to perturbations that occurred during the Anthropocene,2 pre-industrial biodiversity baselines inferred from paleoarchives are needed.3,4 The study of ancient DNA (aDNA) from sediments (sedaDNA)5 has provided valuable information about past dynamics of microbial species6-8 a...

The morphology and internal structure of the Horaine Bank (Bay of Saint-Brieuc, NW France) are described based on multibeam echosounder and high-resolution seismic datasets coupled with vibro-core data. The Horaine Bank shows large-scale bedforms in the lee of a submerged rocky shoal, which allowed defining it as a Banner Bank. The internal structu...

The Holocene period (last 11,700 years BP) has been marked by significant climate variability over decadal to millennial timescales. The underlying mechanisms are still being debated, despite ocean–atmosphere–land connections put forward in many paleo-studies. Among the main drivers, involving a cluster of spectral signatures and shaping the climat...

We discuss paleoenvironments of north-western France over the last 7 kyrs in terms of: i) long-term changes (relative sea-level rise and boreal summer insolation), ii) rapid climate changes (millennial-scale Bond events and multi-decadal regimes of the North Atlantic Oscillation: NAO) and iii) growing human impacts in watersheds. Our study focuses...

Sedimentological, palynological, and micropalaeontological studies carried out throughout the first half of the Holocene, during the Mesolithic/Neolithic transition in the Bay of Brest (i.e. 9200–9000 and 6600–5300 cal. BP) and in the Bay of Douarnenez (i.e. 9200–8400 cal. BP), allowed characterizing coastal environmental changes under the increasi...

Dinoflagellates are part of the marine plankton and about 200 species produce a cyst (dinocyst) during their life cycle, these organic-walled sexually-produced cysts being fossilizable in sediments for hundreds of millions of years. Over the past 40–50 years, dinocysts have led to major advances on Mesozoic-Cenozoic research, in terms of biostratig...

We analyzed a 10-m sediment core retrieved at 82 m water depth off the coast of the Tagus River (Western Iberian Margin, Portugal) to investigate a linkage between variations in benthic foraminiferal assemblages and Tagus River discharge over the last 5700 years. Benthic foraminiferal assemblages were studied at high resolution in combination with...

For the first time a very high resolution palynological study (mean resolution of 1 to 5 years) was carried out over the last 150 years in a French estuarine environment (Bay of Brest; NW France), allowing direct comparison between the evolution of landscapes, surface water, and human practices on Bay of Brest watersheds, through continental (espec...

Modern palynological investigations (pollen and non-pollen palynomorphs) have been carried out for the first time in the entire Bay of Brest (BB; NW France), a semi-enclosed oceanic basin flooded during the Holocene that today is exposed to both marine (North Atlantic surface waters) and fluvial (Aulne and Elorn rivers) influences. Palynological an...

Ce travail de doctorat a pour objectif de comprendre les mécanismes et les réponses régionales de la variabilité climatique Holocène en ciblant plus spécifiquement la Rade de Brest et la Baie de Douarnenez. Dans les environnements côtiers, la vulnérabilité des sociétés humaines face aux aléas climatiques est particulièrement élevée et les pressions...

Ce travail de doctorat a pour objectif de comprendre les mécanismes et les réponses régionales de la variabilité climatique Holocène en ciblant plus spécifiquement la Rade de Brest et la Baie de Douarnenez. Dans les environnements côtiers, la vulnérabilité des sociétés humaines face aux aléas climatiques est particulièrement élevée et les pressions...