Papers by Elodie Brisset
in: Reinhard Bernbeck, Gisela Eberhardt and Susan Pollock (eds.) Coming to Term with the Future: Concepts of Resilience for the Study of Early Iranian Societies, Leiden 2023, 83-96.
This paper aims to investigate episodes of water stress and the human response to them
in the S... more This paper aims to investigate episodes of water stress and the human response to them
in the Southern Zagros Mountains from a long-term perspective. The integrative analysis
of data from different archives allows for identification of phases of drought in the region,
especially starting from the Sasanian period onwards. This investigation also shows that
specific imperial politics such as that of the Sasanian Kings Kawāḏ I and Ḵosrow I helped
to ensure that agricultural communities and practices were sufficiently resilient to these
changes. These politics were essentially based on tax reliefs for in-need farmers and
state investments on the micro-level. However, pastoral and multi-resources lifestyles
remained the ultimate resilience strategies in case of severe aridification.
Quaternary, 2020
We conducted palynological, sedimentological, and chronological analyses of a coastal sediment se... more We conducted palynological, sedimentological, and chronological analyses of a coastal sediment sequence to investigate landscape evolution and agropastoral practices in the Nao Cap region (Spain, Western Mediterranean) since the Holocene. The results allowed for a reconstruction of vegetation, fire, and erosion dynamics in the area, implicating the role of fire in vegetation turnover at 5300 (mesophilous forests replaced by sclerophyllous scrubs) and at 3200 calibrated before present (cal. BP) (more xerophytics). Cereal cultivation was apparent from the beginning of the record, during the Mid-Neolithic period. From 5300 to 3800 cal. BP, long-lasting soil erosion was associated with the presence of cereals, indicating intense land-use during the Chalcolithic and Bronze Age periods. The decline of the agriculture signal and vegetal recolonization is likely explained by land abandonment during the Final Bronze Age. Anthropogenic markers reappeared during the Iberian period when more settlements were present. A contingency of human and environmental agencies was found at 5900, 4200, and 2800 cal. BP, coinciding with abrupt climate events, that have manifested locally in reduced spring discharge, an absence of agropastoral evidence, and a marked decline in settlement densities. This case study, covering five millennia and three climate events, highlights how past climate changes have affected human activities, and also shows that people repeatedly reoccupied the coast once the perturbation was gone. The littoral zone remained attractive for prehistoric communities despite the costs of living in an area exposed to climatic hazards, such as droughts.
Science of The Total Environment, 2019
Volcanism is one of the major natural processes emitting mercury (Hg) to the atmosphere, represen... more Volcanism is one of the major natural processes emitting mercury (Hg) to the atmosphere, representing a significant component of the global Hg budget. The importance of volcanic eruptions for local-scale Hg deposition was investigated using analyses of Hg, inorganic elemental tracers, and organic biomarkers in a sediment sequence from Lake Chungará (4520 m a.s.l.). Environmental change and Hg deposition in the immediate vicinity of the Parinacota volcano were reconstructed over the last 2700 years, encompassing the pre-anthropogenic and an-thropogenic periods. Twenty eruptions delivering large amounts of Hg (1 to 457 μg Hg m −2 yr −1 deposited at the timescale of the event) were locally recorded. Peaks of Hg concentration recorded after most of the eruptions were attributed to a decrease in sedimentation rate together with the rapid re-oxidation of gaseous elemental Hg and deposition with fine particles and incorporation into lake primary producers. Over the study period, the contribution of volcanic emissions has been estimated as 32% of the total Hg input to the lake. Sharp depletions in primary production occurred at each eruption, likely resulting from massive volcaniclastic inputs and changes in the lake-water physico-chemistry. Excluding the volcanic deposition periods, Hg accumulation rates rose from natural background values (1.9 ± 0.5 μg m −2 yr −1) by a factor of 2.3 during the pre-colonial mining period (1400-900 yr cal. BP), and by a factor of 6 and 7.6, respectively, during the Hispanic colonial epoch (400-150 yr cal. BP) and the industrial era (~140 yr cal. BP to present). Altogether, the dataset indicates that lake primary production has been the main, but not limiting, carrier for Hg to the sediment. Volcanic activity and climate change are only secondary drivers of local Hg deposition relative to the magnitude of regional and global anthropogenic emissions.
Global and Planetary Change, 2018
Consecutively to the global sea-level rise, coastal landscapes significantly changed during the E... more Consecutively to the global sea-level rise, coastal landscapes significantly changed during the Early Holocene. We explored how coastal mutations have affected ancient human systems in the western Mediterranean. The Pego-Oliva basin (Spain) provides a thick sediment sequence located in proximity to two well-studied Mesolithic and Neolithic archaeological sites. Based on 16 sediment cores, sedimentological analyses, 14 C dates, and integration of previous works, we reconstructed the architecture of the sedimentary facies and the chronology of deposition for the last 9500 years. From 9500 to 8200 cal. BP, the stepwise inland migration of the coastline is characterised by the deposition of peat layers at distinct depths indicating four phases of barrier-lagoon systems development. The marine transgression caused the disappearance of the lagoon at 8200 cal. BP, and reached a maximum inland position at 7300 cal. BP. Since 5800 cal. BP, sea-level stabilisation induced coastal prograda-tion and barrier-lagoon system construction. Five marine flooding phases dated at 9500, 9100-9000, 8750-8650, 8450-8200, and 8100-7300 cal. BP match Atlantic meltwater pulses. Comparison to archaeology shows that the long-lasting Mesolithic occupation corresponds to the presence of coastal offering easily ex-ploitable local intertidal resources. In contrast, during the Late Mesolithic, we observe a lagoon contraction and the reduction of lagoon bivalves size arguing for a decrease in resource productivity. This changes in the lagoon ecosystems negatively impacted to Late Mesolithic populations leading to a less intense occupation of this area. Therefore, the 700 years' temporal hiatus between the last hunter-gatherers and the first farmers occupying this area is explained by the disappearance of the formerly exploited biotopes because of sea-level rise, a situation that may have been aggravated by coincidence of the 8200 cal. BP climate event. The maximal sea transgression corresponded to a shift from intertidal to infralittoral species between the Impressa/Precardial and the Postcardial Neolithic, indicating a good adaptation to changing environments at that time. However, comparison between Late Mesolithic to Early Neolithic suggests that communities with different cultural baggage have had a different perception of the same environment. By the past perspective, it emphasises that perception of the ecosystem value as a benefit or constraint, and of the risks associated with sea-level rise, relies first on the local and regional scales adaptive capacity of society to global changes.
J Paleolimnol, 2019
Sedimentological (dry density, micro-fa-cies analysis on thin-slides, X-ray diffraction, layer co... more Sedimentological (dry density, micro-fa-cies analysis on thin-slides, X-ray diffraction, layer counting) and elemental analyses (X-ray fluorescence) of a 3.5-m-long sediment core (MAH-B) from saline Lake Maharlou (SW Iran) were used to infer hydrological changes over the last * 3800 years. The sediment consists of thin, alternating beds of evapor-ites (halite, gypsum), carbonates (calcite, aragonite) and detrital minerals (quartz, muscovite, chlorite). We interpret the data with respect to three main hydrologic conditions: (1) nearly complete desiccation of the lake, marked by frequent halite layers, (2) hypersaline conditions marked by gypsum abundance, (3) wet conditions, characterized by high river-borne terrige-nous sediment input with high potassium content. Distinct flood layers indicate fluvial activity. From about 3800-2000 cal year BP, terrigenous sediment supply was high, with peaks at 3700-3650, 3500-3450, and 3400-3250 cal year BP. Evaporative conditions were not common. From ca. 2000 cal year BP to present, detrital minerals are less abundant, and the increase in gypsum abundance suggests drier climate with enhanced evaporation. Frequent desiccation events occurred from 1100 to 700 cal year BP. The late Holocene hydrology of Lake Maharlou corresponds well with records of dune formation and phases of river alluviation in Iran and the Arabian Peninsula, and with regional speleothem records. In addition to the influence of climate change on the lake hydrology, ancient humans modified water drainage in the catchment. Periods of subterranean tunnel (qanats) use correspond to dramatic shrinkage of the water body. We propose that climate changes drove long-term water shortages that were enhanced by anthro-pogenic activities, leading to more frequent desiccation of the lake during the last millennium.
Journal of Paleolimnology
We reconstructed the paleohydrologic and climatic history of the Lake Neor region, NW Iran, from ... more We reconstructed the paleohydrologic and climatic history of the Lake Neor region, NW Iran, from the end of the late glacial to the middle Holocene (15,500-7500 cal yr BP). Subfossil chironomid and pollen assemblages in a sediment core from a peatland located south of Lake Neor enabled identification of four main hydrologic phases. The period 15,500-12,700 cal yr BP was characterized by a relatively dry climate with an open landscape, suggested by the abundance of Irano-Turanian steppe plants (e.g. Amaranthaceae, Artemisia and Cousinia). Dominance of several shallow-water and semi-terrestrial chironomid taxa (e.g. Pseudosmittia, Smittia/ Parasmittia and Paraphaenocladius/Parametriocnemus) during this period is indicative of lower water tables in the wetland. Between 12,700 and 11,300 cal yr BP, chironomid taxa indicate higher wetland water tables, as suggested by the presence of Zavrelia, Chironomus anthracinus/plumosus-type and Micropsectra, which are inhabitants of open-water, lacustrine areas. The open-steppe vegetation remained dominant in the watershed during this time. Increasing wetland moisture could be explained by: (1) cool summers that reduced the evaporation rate; and/or (2) a decrease in duration of the summer dry season. The period 11,300-8700 cal yr BP was characterized by lower wetland moisture, contemporaneous with a delay in the expansion of deciduous forest, suggesting persistent dry climate conditions throughout the beginning of the Holocene, which may have been related to the intensified seasonality of precipitation. Around 8700 cal yr BP, higher wetland water levels, inferred from chironomids, occurred simultaneously with the onset of regional deciduous forest expansion, probably caused by a shortening of the summer dry period. We concluded that chironomids are appropriate paleoecological proxies to investigate global and local hydrologic variability in the Middle East.
Quaternary Science Reviews, 2015
Citation Elodie Brisset, Frédéric Guiter, Cécile Miramont, Marie Revel, Edward J. Anthony, Claire... more Citation Elodie Brisset, Frédéric Guiter, Cécile Miramont, Marie Revel, Edward J. Anthony, Claire Delhon, Fabien Arnaud, Emmanuel Malet, Jacques-Louis de Beaulieu, 2015. Lateglacial/Holocene environmental changes in the Mediterranean Alps inferred from lacustrine sediments, Quaternary Science Reviews, Volume 110, pages 49-71. http://dx.
The Holocene, 2015
Sediments from Lake Petit (2200 m a.s.l., Southern Alps) are particularly relevant for analysis o... more Sediments from Lake Petit (2200 m a.s.l., Southern Alps) are particularly relevant for analysis of coupled landscape palaeoecology and palaeolimnology. Diatom assemblages, organic matter composition of sediments (total nitrogen and organic carbon) and Pediastrum boryanum concentrations were obtained from a 144 cm-long core, enabling the reconstruction of the aquatic ecosystem over nearly the last 5000 cal. BP. From 4800 to 4300 cal. BP, Lake Petit was a stable diatom productive water body dominated by alkaliphilous diatoms (Staurosirella pinnata). During this period, nutrients and cations were supplied by the chemical weathering of podzols that developed under conifer woodlands. This overall stability was suddenly interrupted at 4200 cal. BP by a major detrital pulse that was probably climate-linked (4200 cal. BP event) and that triggered a drop in diatom productivity and diversity. From 4100 to 2400 cal. BP, diatom productivity progressively decreased whereas Pediastrum developed. Diatom assemblages were more diversified (predominance of Pseudostaurosira robusta, P. brevistriata and P. pseudoconstruens) and reflected a regime of continuous erosion, whereas slopes were colonised by grazed grasslands. Finally, from 2400 cal. BP to the present day, diatom assemblages reveal a slight acidification and nutrient enrichment of waters concomitant with increasing human pressure in the catchment. These results demonstrate the close links between ecosystems and the ready propagation of disturbances throughout watersheds that might lead to abrupt regime shifts in such alpine environments.
Quaternaire, 2014
ABSTRACT This study presents new 14C AMS ages obtained from the sedimentary sequence of Lake Allo... more ABSTRACT This study presents new 14C AMS ages obtained from the sedimentary sequence of Lake Allos (elevation: 2,230 m, Verdon valley, Southern Alps, France). These ages provide new evidence on the last deglaciation over the Southern Alps, enabling us to revise the chronological framework previously established. Sedimentation in the lake began between 12,300 and 13,500 cal. yr BP (2 sigma interval). The two glacial stages identified in a cirque downstream of Lake Allos (at 1,900 m a.s.l.) and on the glacial threshold (at 2,300 m a.s.l.) are hence older. Our results are in good agreement with previous conclusions based on palynological evidence from high-elevations peat bogs and lakes that suggested an earlier deglaciation, at the onset of the Lateglacial.
A 144-cm-long core was obtained in Lake Petit (2200 m a.s.l., Mediterranean French Alps) in order... more A 144-cm-long core was obtained in Lake Petit (2200 m a.s.l., Mediterranean French Alps) in order to reconstruct past interactions between humans, the environment and the climate over the last five millennia using a multidisciplinary approach involving sedimentological, geochemical and botanical analyses. We show a complex pattern of environmental transformation. From 4800 to 4200 cal. BP, podzol-type soils progressively developed under forest cover. This stable situation was interrupted by a major detrital pulse at 4200 cal. BP that we consider as a tipping point in the environmental history. At this point, pedogenetic processes drastically regressed, leading to the development of moderately weathered soils. More frequent detrital inputs are recorded since 3000 cal. BP (ad 1050) as the human impact significantly increased in the catchment area. We conclude that destabilisation of the environment was triggered by climate and exacerbated by human activities to a stage beyond resilience.
and sharing with colleagues.
Journal of Paleolimnology, 2014
Quaternary Research, 2012
Investigation of Lake Allos sediments revealed ~160 graded layers, interpreted as flood deposits,... more Investigation of Lake Allos sediments revealed ~160 graded layers, interpreted as flood deposits, over the last 1400 yr. Comparisons with records of historic floods support the interpretation of flood deposits and suggest that most recorded flood events are the result of intense meso-scale precipitation events. As there is no evidence for any major changes in erosion processes in the catchment since the Medieval Warm Period (MWP), we interpret the Allos record in terms of repeated intense precipitation events over the last millennium, with a low flood frequency during the MWP and more frequent and more intense events during the Little Ice Age. This interpretation is consistent with the pattern of increasingly humid conditions in the northwestern Mediterranean region. This long-term trend is superimposed on high frequency oscillations that correlate with solar activity and autumnal North Atlantic Oscillation (NAO). Finally, a comparison of flood records across the northwestern Mediterranean region showed that intense precipitation events in Allos (east of the Rhône Valley)
Within the context of increasing demographic pressures and hazards related to climate change, the... more Within the context of increasing demographic pressures and hazards related to climate change, the problems posed by landscape erosion have become particularly crucial. The current management of Mediterranean mountain environments, which are highly exposed to erosion hazards, needs to be supported by a thorough understanding of their susceptibility to these hazards and their long-term trajectories. A retrospective analysis of environmental trajectories has been conducted from the study of three lacustrine sedimentary archives in the Southern Alps (Lakes Petit, Vens and Allos). This multi-disciplinary study, based on sedimentology, geochemistry and palynology, has enabled characterization of the dynamics of erosion and changes in plant cover over the last 14,000 years. In Lakes Allos and Vens, the start of the Holocene is marked by the maturing of ecosystems, by chemical weathering of soils and by forest encroachment at higher altitudes. These environmental changes resulted in progres...
News by Elodie Brisset
Session #420: Over the past years, the study of Early to Mid-Holocene coastal adaptations has eme... more Session #420: Over the past years, the study of Early to Mid-Holocene coastal adaptations has emerged as a key research topic to understand processes of economic intensification and human resilience to environmental change. As the sea level rose during the Lateglacial Interstadial coastal configuration dramatically changed, inducing sedimentary infilling of estuaries and bays. Those sea-level changes were translated into loss of human settlement areas, reduction of hunting territories, and modification of coastal biotopes. A key debated issue, is to determine to what extent Early to Mid-Holocene changes on coastal biotopes and marine biological productivity affected patterns of human exploitation of coastal resources. This session aims to present new multidisciplinary findings that include:
• Archaeological records of the Mesolithic and Neolithic periods both in terms of change in settlement distribution over time along coasts and hinterlands, and in past dietaries (bioarchaeological remains of animals - invertebrates and vertebrates- as well as geochemical analysis);
• Paleogeographical studies recording geosystem adjustment to sea-level rise (multiple-core analysis, 3D modelling, time-slice reconstruction);
• Paleoecological studies focusing in coastal biotope reconstructions (palynology, aquatic fauna, geochemical analysis);
• Spatial and temporal correlations between archaeological and palaeoenvironmental records of the socio-ecosystem changes;
• Comparisons of European coastal areas (Mediterranean, Atlantic, Baltic, Black Sea) in order to highlight similarities and discrepancies.
Thus, we encourage participation of researchers that are interested in understanding of past human-coastal environment feedbacks during the Early to Mid-Holocene. Ultimately, this session aims to take benefit of past evidences in order to better understand resilience of societies to current global changes.
Papers since 2000 by Elodie Brisset
Nature: Scientific Reports, 2019
Over the last decade, an increasing number of studies have used lake sediment DNA to trace past l... more Over the last decade, an increasing number of studies have used lake sediment DNA to trace past landscape changes, agricultural activities or human presence. However, the processes responsible for lake sediment formation and sediment properties might affect DNA records via taphonomic and analytical processes. It is crucial to understand these processes to ensure reliable interpretations for “palaeo” studies. Here, we combined plant and mammal DNA metabarcoding analyses with sedimentological and geochemical analyses from three lake-catchment systems that are characterised by different erosion dynamics. The new insights derived from this approach elucidate and assess issues relating to DNA sources and transfer processes. The sources of eroded materials strongly affect the “catchment-DNA” concentration in the sediments. For instance, erosion of upper organic and organo-mineral soil horizons provides a higher amount of plant DNA in lake sediments than deep horizons, bare soils or glacial flours. Moreover, high erosion rates, along with a well-developed hydrographic network, are proposed as factors positively affecting the representation of the catchment flora. The development of open and agricultural landscapes, which favour the erosion, could thus bias the reconstructed landscape trajectory but help the record of these human activities. Regarding domestic animals, pastoral practices and animal behaviour might affect their DNA record because they control the type of source of DNA (“point” vs. “diffuse”).
Papers (Andean Archaeology) by Elodie Brisset
Anthropocène, 2021
Copper, silver, and gold exploitation has been a foundation of economic and socio-cultural develo... more Copper, silver, and gold exploitation has been a foundation of economic and socio-cultural development of Andean societies, at least for the last three millennia. The main centers of pre-colonial metallurgy are well-known from archeological artifacts, but temporal gaps inherent in this record handicap a finer understanding of the modalities of ore exploitation by succeeding civilizations. A continuous record over time of trace metals emitted during ore smelting operations make lake sediments excellent candidates to fill those gaps. Two millennia of metallurgy were reconstructed from atmospherically derived metals together with lead (Pb) isotope ratios in two dated sediment cores from Lake Titicaca. The first evidence for metallurgy is found during the apogee of the Tiwanaku state (AD 800 –1150), with a higher copper (Cu) accumulation that can be attributed to the smelting of local Cu ores, based on Pb isotopic fingerprinting. During the Late Intermediate Period (AD 1150 –1450), recorded peaks in metal deposition that persisted for twenty years show that mining activities were intensive but discontinuous. Pb isotope ratios suggest diversi fied extractive activities, mainly located in the southern part of the central Altiplano. Finally, the most intense mining epoch began during the Inca Empire (ca. AD 1500) and lasted until the end of the Colonial Period (AD 1830), with unprecedented metal deposition over this interval. Pb isotope fingerprinting shows that mining operations occurred mainly in the Lake Titicaca and Potosi areas and were responsible for metal emissions recorded in the entire Altiplano, as evidenced by other studies.
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Papers by Elodie Brisset
in the Southern Zagros Mountains from a long-term perspective. The integrative analysis
of data from different archives allows for identification of phases of drought in the region,
especially starting from the Sasanian period onwards. This investigation also shows that
specific imperial politics such as that of the Sasanian Kings Kawāḏ I and Ḵosrow I helped
to ensure that agricultural communities and practices were sufficiently resilient to these
changes. These politics were essentially based on tax reliefs for in-need farmers and
state investments on the micro-level. However, pastoral and multi-resources lifestyles
remained the ultimate resilience strategies in case of severe aridification.
News by Elodie Brisset
• Archaeological records of the Mesolithic and Neolithic periods both in terms of change in settlement distribution over time along coasts and hinterlands, and in past dietaries (bioarchaeological remains of animals - invertebrates and vertebrates- as well as geochemical analysis);
• Paleogeographical studies recording geosystem adjustment to sea-level rise (multiple-core analysis, 3D modelling, time-slice reconstruction);
• Paleoecological studies focusing in coastal biotope reconstructions (palynology, aquatic fauna, geochemical analysis);
• Spatial and temporal correlations between archaeological and palaeoenvironmental records of the socio-ecosystem changes;
• Comparisons of European coastal areas (Mediterranean, Atlantic, Baltic, Black Sea) in order to highlight similarities and discrepancies.
Thus, we encourage participation of researchers that are interested in understanding of past human-coastal environment feedbacks during the Early to Mid-Holocene. Ultimately, this session aims to take benefit of past evidences in order to better understand resilience of societies to current global changes.
Papers since 2000 by Elodie Brisset
Papers (Andean Archaeology) by Elodie Brisset
in the Southern Zagros Mountains from a long-term perspective. The integrative analysis
of data from different archives allows for identification of phases of drought in the region,
especially starting from the Sasanian period onwards. This investigation also shows that
specific imperial politics such as that of the Sasanian Kings Kawāḏ I and Ḵosrow I helped
to ensure that agricultural communities and practices were sufficiently resilient to these
changes. These politics were essentially based on tax reliefs for in-need farmers and
state investments on the micro-level. However, pastoral and multi-resources lifestyles
remained the ultimate resilience strategies in case of severe aridification.
• Archaeological records of the Mesolithic and Neolithic periods both in terms of change in settlement distribution over time along coasts and hinterlands, and in past dietaries (bioarchaeological remains of animals - invertebrates and vertebrates- as well as geochemical analysis);
• Paleogeographical studies recording geosystem adjustment to sea-level rise (multiple-core analysis, 3D modelling, time-slice reconstruction);
• Paleoecological studies focusing in coastal biotope reconstructions (palynology, aquatic fauna, geochemical analysis);
• Spatial and temporal correlations between archaeological and palaeoenvironmental records of the socio-ecosystem changes;
• Comparisons of European coastal areas (Mediterranean, Atlantic, Baltic, Black Sea) in order to highlight similarities and discrepancies.
Thus, we encourage participation of researchers that are interested in understanding of past human-coastal environment feedbacks during the Early to Mid-Holocene. Ultimately, this session aims to take benefit of past evidences in order to better understand resilience of societies to current global changes.