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To cite this version:Alexa Dufraisse, Sylvie Coubray, Olivier Girardclos, Noémie Nocus, Michel Lemoine, et al.. Anthracotypology as a key approach to past firewood exploitation and woodland management reconstructions. Dendrological reference dataset modelling with dendro-anthracological tools. Quaternary International, Elsevier, 2018, 463 (part B) Charcoal analysis aims to study different aspects of forest management, techno-19 economical choices and their specific impact on past landscapes, as well as the impact of 20 climatic events. However, at the present time, charcoal analysis is generally limited to the 21 study of a list of taxa and their relative frequency, as the methods usually employed in 22 dendrochronology to characterize past woodland, based on long tree-ring series, are not 23 suitable for anthracological material. Today, the new challenge for charcoal analysis is thus 24 to develop adapted dendrological tools. In this context, the aim of the ANR DENDRAC 25 project "Development of dendrometrical tools applied to anthracology: study of the 26 interactions between Man, resources and environments" was to characterize modern-day 27 wood stands in accordance with historical woodland practices and convert dendroecological 28 R e v i s e d m a n u s c r i p t 2 data into parameters adapted to charcoal analysis. The purpose of this study is to define the 29 dendrological features with the help of the anthracological tools without explaining the 30 observed differences between the sampled stands (given the stational variability, age and 31 regeneration modes). The first step consisted in creating dendro-anthracological tools based 32 on morpho-anatomical criteria that help to characterize growth, distinguish heartwood from 33 sapwood and evaluate charcoal-pith distance. The second step involves characterizing three 34 modern-day wood stands (coppice under standard, high forest and young stand formed by a 35 mixture of seeded and coppice trees), defined by their structure, stand density and 36 regeneration modes, using dendrological data measured on fresh wood material and 37 modelled into anthracological data with the dendro-anthracological tools. In this way, 38 anthracological types were defined for each wood stand, forming anthraco-typological 39 models, which area useful for the interpretation of archaeological charcoal assemblages. 40Finally, an anthracological key is proposed to sort archaeological charcoal fragments in 41 anthraco-groups before data processing. 42 43

Data concerning driftwood is of value to researchers in fields as diverse as oceanography, geomorphology, and human occupation. Yet studies on the subject in the Canadian Arctic have only recently been carried out, and the present study is the first in Nunavik (northeastern Canada). This paper documents the composition, characteristics, and origin of modern driftwood pieces on the beaches of the eastern coast of Hudson Bay. A total of 1057 samples from Ivujivik, Akulivik, Inukjuak, and Umiujaq were identified as belonging to four coniferous species (Picea sp., Larix sp., Abies sp. likely balsamea, and Thuja sp. likely occidentalis) and four deciduous species (Salix sp., Populus sp., Alnus sp., and Betula sp., likely papyrifera). Spruce largely predominate; white birch, white cedar, and fir are rare. The presence of the latter species proves that some of the wood originated from south-southeast of James Bay. Driftwood found in the southern area (Umiujaq) are more numerous, larger, and less degraded than driftwood in the north (Ivujivik). However, many large coniferous samples were found as far north as Akulivik, indicating that they likely traveled a great distance, unlike the smaller wood specimens (especially deciduous samples). All of the wood that we analyzed died relatively young, with an average age of 63 years for conifers and 23 years for deciduous. Measurements of ring widths and the cross-dating of samples with existing reference chronologies of living trees along Hudson Bay and James Bay revealed several possible correlations and origins for wood found in same areas.

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Le niveau coquillier de Beg-an-Dorchenn (Plomeur, Finistère) a fait l’objet d’une étude interdisciplinaire visant, d’une part à calculer la valeur de l’effet réservoir pour cette zone du littoral atlantique, d’autre part à comprendre comment les hommes du Mésolithique installés à proximité de la mer ont exploité leur environnement, à partir notamment d’un sondage de 2 m2 réalisé en 2001. Par la datation conjointe de sept coquilles et d’un charbon, il semble que l’âge apparent de la mer à cet endroit au Mésolithique final soit de 180 ± 65, avec un R de -260 ± 65. La date de constitution de ce niveau coquillier se place dans l’intervalle 5640-5550 avant notre ère. Le tamisage fin (2 mm) opéré sur le site permet d’obtenir une vision plus complète du mode de vie et des industries lithiques. Ce mode d’échantillonnage montre que de petits restes autrefois négligés comme les fragments de doigts de crabe sont les témoins de ressources alimentaires qui ont pu composer une part non négligeable des régimes alimentaires. Les armatures lithiques sont principalement des trapèzes symétriques à troncatures concaves caractéristiques du faciès Beg-er-Vil du Téviecien. Les ressources marines identifiées (coquillages, crabes, poissons, oiseaux) correspondent à une exploitation très diversifiée des environnements marins accessibles près du site de Beg-an-Dorchenn à marée basse. Les mammifères terrestres et les végétaux correspondent également à une exploitation locale des ressources. La combinaison des moments potentiels d’accès à l’ensemble des ressources alimentaires permet d’émettre des hypothèses quant au mode de résidence de ces dernières populations mésolithiques. Si des marqueurs indiquent clairement une occupation à la belle saison (poissons et coquillages), la disponibilité des ressources marines autoriserait une occupation à n’importe quel autre moment, en continu ou non.

Eighty-four specimens of wood collected in northeastern North America from pre-identified conifers were used to define new anatomical criteria to distinguish woody macroremains of Picea mariana, Picea glauca and Larix laricina. In addition to characters already described in the literature, the torus surface of bordered pits along the longitudinal tracheids were demonstrated to be a very good distinction criterion. The distinction between Picea glauca and P. mariana is based on the seriation of bordered pits on the tracheids of the rays. As a method of species distinction, we suggest a dichotomous classification based on the dominance of uniseriate or biseriate pits. In the wood collection studied, 69 % of radial tracheids were predominantly biseriated in Picea mariana, compared with only 28 % in Picea glauca. These simple distinction methods are only applicable in cases where no other Picea species could cause confusion in batches of woody and charred sub-fossils. They add a practical tool for further paleoecological reconstructions in northeastern North America.Quatre-vingt-quatre spécimens de bois de conifères récoltés sur un vaste territoire dans le nord-est de l'Amérique du Nord ont servi à définir de nouveaux critères de distinction anatomique entre Picea mariana, Picea glauca et Larix laricina. En plus des critères habituellement décrits dans la littérature, l'état de surface du torus des ponctuations aréolées des trachéides longitudinales chez Larix laricina est présenté comme un excellent élément de détermination, facilement accessible. La distinction entre Picea glauca et P. mariana peut être faite par l'examen de la sériation des ponctuations des trachéides des rayons ligneux. Une classification dichotomique des croisements des cellules dans les rayons sur la base de la dominance de l'unisériation ou de la bisériation des ponctuations des trachéides de rayon est proposée comme méthode de distinction des espèces en plus d'autres caractères reconnus dans la littérature. Ainsi, chez Picea mariana, plus de 69 % des trachéides radiales sont à dominante bisériée et seulement 28 % chez Picea glauca. En présence de lots de macrorestes ligneux subfossiles gorgés d'eau ou carbonisés où seule la présence de ces deux espèces d'épinettes est possible, ces méthodes simples d'identification ouvrent de nouvelles perspectives dans le domaine de la recherche paléoécologique des milieux boréaux nord-américains.Vierundachtzig Holzproben von Tannenholz wurden auf einem ausgedehnten Gebiet im Nordosten Nordamerikas gesam- melt und dienten dazu, neue Kriterien zur anatomischen Unterscheidung zwischen Picea mariana, Picea glauca und Larix laricina zu definieren. Zusätzlich zu den gewöhnlich in der Literatur beschriebenen Kriterien wird die Torus-Oberfläche des Rands der gepunkteten Vertiefungen der Längs-Tracheen bei Larix laricina als ausgezeichnetes, leicht zugängliches Bestimmungselement beschrieben. Zwischen Picea glauca/Picea mariana kann durch die Untersuchung der Serienfolge der gepunkteten Tracheen auf den Holzringen u...

From 1989 to 1991, a rescue-dig took place at Poses, «Le Vivier- Le Clos-Saint-Quentin». The area studied is situated on the flood-plain, which explains in this place important alluvial deposits, and consequently exceptionnal conservation of neolithic and chalcolithic seulement levels. On four hectares, the excavation has induced the study of seven settlements and also secondary areas (particularly combustion structures of polynesian type and accumulation of blocks of sandstone). The two oldest settlements belong to the «post-rubané» cultures (Villeneuve-Saint-Germain, Cerny) and the five others to the chalcolithic cultures. The most important resuit concerns, on one hand, the first neolithisation of the country and, on the other hand, the development of a chrono-cultural framework for the Late Neolithic - Early Bronze Age transition. The excavations have shown the existence of original late neolithic features (assemblages 3 and 4), have confirmed the large impact of Bell Beakers espansion in a late time in the Lower Valley of the Seine River and their evolution (assemblages 5 and 6), and finally have allowed to discover an unknown chalcolithic feature (assemblage 7). This operation enables us also to approach the theme of the development of marginal lands in areas liable to flooding.