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Analysis of charcoal particles preserved in lake sediments has been frequently used to reconstruct fire, vegetation and climate history. Larger macroscopic particles (>125 μm) are attributed to local fires, whereas microscopic charcoal particles (<125 μm), observed on pollen slides, are a signal of regional fire. Taxonomic identification of the charcoal particles adds to the fire-history reconstruction by providing information about fuel composition and past fire conditions. Identification of charcoal can unravel one of the longstanding questions regarding past fire regimes, namely what was burning. This paper describes an analysis of charcoal particles preserved in the sediments of a small closed-basin lake in Yellowstone National Park. Blacktail Pond (44.954°N, 110.604°W; 2012 m elev) is located in steppe vegetation surrounded by conifer forest. Previous studies of the site have presented a multi-proxy environmental history of the last 14,650 years. The focus of this investigation was on the fire history of the early-Holocene (11,500–9900 cal yr BP). Thirty-nine sediment samples were taken at 0.5 cm intervals to examine macroscopic charcoal particles, with attention on two large charcoal peaks at 10,970 and 10,200 cal yr BP that registered large or near-site fires. Twenty-eight samples contained 243 large-enough particles (180–250 μm) to be examined with scanning electron microscopy. We were able to identify charcoal of conifers (Pinus , Picea, and Abies or Juniperus), Artemisia and unidentified deciduous shrubs, and unidentified monocotyledons. The first fire burned a mixture of fuels, whereas the second episode burned Artemisia , shrubs and herbs but no conifers. The results are consistent with previous pollen interpretations at Blacktail Pond that indicate an open mixed-conifer forest in the early Holocene prior to 10,750 cal yr BP, replaced by Pinus contorta forest on the slopes and steppe in the valley. The relative dominance of Pinus contorta -type charcoal points to the importance of fire as a catalyst for the spread of this species. [ABSTRACT FROM AUTHOR]

Qikirtajuaq is a long island facing the Inuit village of Akulivik on the northeastern coast of Hudson Bay (Canada) that is rich in archaeological sites. Kangiakallak‐1 (JeGn‐2), one of the main sites on this island, is a large multicomponent site that includes Dorset and Thule Inuit winter houses. This study documents the dynamics of palaeoenvironmental conditions in the successive occupations of the Kangiakallak‐1 settlement based on plant macrofossils, pollen and non‐pollen palynomorph analyses and archaeological research. The data indicate that Dorset inhabitants constructed their dwelling at about 772 cal. a BP. The site was reused by the Thule Inuit a few decades later, starting at about 671 cal. a BP. Thus, Kangiakallak‐1 is one of the few sites, at least in Nunavik (northern Québec, Canada), that were rapidly reoccupied by the Thule Inuit after the departure of the Dorset inhabitants, which indicates a possible overlap between the two cultures in the Akulivik region. The palaeoecological data show that both Dorset and Thule inhabitants left clear footprints at the local scale in the form of several nitrophilous species that became established in and near the houses and persisted over a long period. The deposition of domestic waste (including bone fragments, skin, burnt fat and charcoal fragments) inside the subterranean dwellings fertilized the soil and led to the growth of unique nitrophilous plants. These changes transformed the houses into exceptional floristic refuges. [ABSTRACT FROM AUTHOR]

Various studies using pollen stratigraphies have demonstrated significant correlations between Holocene plant diversity, climate, and human activities. Studies that have analyzed longer Holocene timescales tend to discuss cultural data very superficially. This is remarkable because detailed insights into past human activities may be key to gain an understanding of the observed trends in biodiversity. This study aims to reconstruct and explain spatio-temporal trends in past plant diversity (alpha, temporal, and spatial beta diversity) by integrating data on vegetation dynamics, human subsistence economy, and land-use patterns. The landscape of Northwest France during the greater part of the Iron Age and the start of the Roman period (600 BC–AD 100) is selected as a case study. In total, 30 high-quality pollen-stratigraphical sequences allow for the reconstruction of the main long-term trends in plant diversity and more generally of the changing fabric of the landscape. Additionally, increasingly detailed images of the Iron Age rural landscape are available because of a steep increase in archaeological data (aerial photography, surveys, and excavations). These different types of data are integrated and used as input for a wider discussion on the relation between human activities and plant diversity. In general, the taxonomic richness increases steadily during the period under study. Some spatio-temporal differences are observed. The increasing richness values correspond with the growing impact of human activities on the landscape. Archaeologically documented land-use changes on smaller timescales are less clearly reflected in the richness values and vegetation dynamics, which might result from the (large-scale) research design. [ABSTRACT FROM AUTHOR]

Excavations conducted at the site of Gegharot in north central Armenia, along the northeastern margin of the Tsaghkahovit Plain (Aragatsotn region) have produced a large quantity of well-preserved charcoals. With occupations dating to the Early and Late Bronze Age, the site has been excavated since 2000 under the supervision of R. Badalyan and A.T. Smith under the auspices of the joint Armenian-American Project ArAGATS. The examination of the wood anatomy along three sections under a reflected light microscope, necessary for the identifications of charcoals, was systematically undertaken completed with the observation of the ligneous structure on transverse sections using a stereomicroscope. This dendrological approach provides valuable data for aiding identification of which part of the tree used, recording growth ring width, estimating wood diameter, and ascertaining the state of the wood before carbonization. Different vegetational biotopes were identified from remains of the Early Bronze Age layers at the site: an open woodland with heliophilic shrubs (birch, maple, willow and Pomoïdeae ), an open forest formation with notably oak with maple and ash trees and a wet zone with willows and ash trees. The estimated diameters of the wood used at that time did not exceed 12 cm. The wood collection from the Late Bronze Age levels indicates a pine and oak forest surrounded by open areas where birch trees and Pomoïdeae grew and wetlands with willow trees and elm as riparian forests. The onset of a colder and drier climate could be the cause of the disappearance of the ash trees, the appearance of oak pine forests and the reduced growth of the tree-ring width. The taxa list and the high frequency of the small diameters observed during both occupations can refer to a local woodland exploitation. According to the observation of the last ring before the bark, evidence from a single operation (T21), during the Late Bronze Age testifies to seasonal activities. Some large charcoals of pine or oak had exceptional long series of more than 60 tree-rings. The average curve built on the basis of the oak series has a length of 72 rings, the beginning of a tree-ring series building in Armenia for the Bronze Age. [ABSTRACT FROM AUTHOR]

Abstract: During the last 15years, charcoal analysis of archaeological sites in north-western France has been carried out in conjunction with systematic and detailed dendrological examination. By considering these extrinsic criteria in association with the analytical results, palaeo-ethnographic and palaeo-environmental information can be obtained. The charcoals are classically identified under the microscope on the basis of their cellular structure. This examination is associated with an observation of the ligneous structure on transverse sections using a binocular lens. When charcoal fragments are large enough, the growth ring widths are measured. Tree ring curvature is also noted. Finally, alteration by fusion or radial cracks, the presence of fungal hyphae, and insect degradation are also recorded. Results are thus obtained on the nature of fuel used in domestic fireplaces and kilns. The selection of timbers and their catchment areas are also revealed. The average width of the growth rings in oak charcoal from domestic hearths coming from about forty sites in north-western France shows a significant increase from 6000 to 2000 BP. There is a similar increase in the number of heliophilic taxa used from the Neolithic to the Iron Age. This implies that the environment became more and more open because of use by society. The interpretation of the dendrology results applied to charcoal analyses is obtained through a convergence of criteria. Thus, charcoal analysis can provide more than just an identification of the species used, and can yield fundamental information on the interaction of society with the environment. [Copyright &y& Elsevier]

• High complementarity between spider and vascular plants as ecological indicators in peat bogs. • High complementarity between diversity metrics in the understanding of ecological patterns. • Landscape and local factors as interwoven structuring drivers of community in peat bogs. Despite their specific biodiversity and the ecosystem services they furnish, peat bogs remain poorly understood, especially in terms of their responses to changes at multiple spatial scales. Many subarctic peat systems face acute risks, due to current global change. In this study, using a multi-metric approach, we assessed the relative value of plants and spiders as ecological indicators in contrasted peat bogs of a French archipelago (St. Pierre-et-Miquelon), located in the North Atlantic. In 2021, pitfall trapping and suction sampling collected spiders while phytosociological relevés were used to document vascular plants. A total of 69 species of spiders and 38 species of vascular plants were identified, and both taxonomic (TD) and functional (FD, based on traits related to dispersal, size and ecosystem functioning) diversity were then estimated for three levels of species relative abundance (Hill numbers q = 0, 1 and 2) using the iNEXT 3D package for alpha diversity as well as iNEXT beta3D for beta diversity. As expected, patterns of TD and FD were highly correlated for each Hill number, but also between Hill numbers for spiders, indicating a surprisingly low effect of species abundance on (spider) diversity patterns. On the contrary, differences between sites were more visible for plants species when species coverage was considered (q = 1 and q = 2), for both TD and FD, and for alpha and beta diversity. RLQ and Fourth corner analyses indicated differences based on functional traits between sites which were significantly associated with relationships between dispersal modes and mostly local factors for plant assemblages. Finally, variance partitioning on assemblage composition showed the importance of an interaction between local and landscape factors for both plants and spiders, with a relatively high importance of local factors alone for plants. Our study thus revealed the high complementary of spider vs. plant assemblage-based metrics as indicators of changing local conditions in peat bogs, confirming these both experience rapid change in subarctic climates. [ABSTRACT FROM AUTHOR]

A multidisciplinary geoarchaeological investigation was performed at Paaliup Qarmangit 1 site (JjGj‐14), located in a valley affected by periglacial processes in Nunavik, Canada. A taphonomic approach was carried out to document site formation processes on the site of a single‐family semi‐subterranean winter Thule‐Inuit house. Off‐site geomorphological and stratigraphical analyses enabled us to reconstruct the sedimentary environment in the valley since the last glaciation. Valley shoreline sediments deposited during the marine regression were reworked by eolian, runoff, and periglacial processes. The site was first used by Dorset people after 143‐327 cal A.D. and then by the Thule‐Inuit between 1317–1413 cal A.D. and 1466–1642 cal A.D. Strategic features of the site, such as the availability of building material, food, and water resources may explain its sucessive use by two different cultures. On‐site, stratigraphical, micromorphological, and macrofossil analyses showed the predominance of niveo‐eolian and nivation processes in landscape and site formations. The archaeological record reveals the action of niveo‐eolian processes throughout the Medieval Climatic Optimum and the Little Ice Age, likely due to local factors, site location, and the bowl‐shape of the semi‐subterranean house. Macrofossil data and radiocarbon dating indicate postdepositional natural and/or anthropogenic reworking of Dorset artefacts. [ABSTRACT FROM AUTHOR]

Charcoal analysis aims to study different aspects of forest management, techno-economical choices and their specific impact on past landscapes, as well as the impact of climatic events. However, at the present time, charcoal analysis is generally limited to the study of a list of taxa and their relative frequency, as the methods usually employed in dendrochronology to characterize past woodland, based on long tree-ring series, are not suitable for anthracological material. Today, the new challenge for charcoal analysis is thus to develop adapted dendrological tools. In this context, the aim of the ANR DENDRAC project “ Development of dendrometrical tools applied to anthracology: study of the interactions between Man, resources and environments” was to characterize modern-day wood stands in accordance with historical woodland practices and convert dendroecological data into parameters adapted to charcoal analysis. The purpose of this study is to define the dendrological features with the help of the anthracological tools without explaining the observed differences between the sampled stands (given the stational variability, age and regeneration modes). The first step consisted in creating dendro-anthracological tools based on morpho-anatomical criteria that help to characterize growth, distinguish heartwood from sapwood and evaluate charcoal-pith distance. The second step involves characterizing three modern-day wood stands (coppice under standard, high forest and young stand formed by a mixture of seeded and coppice trees), defined by their structure, stand density and regeneration modes, using dendrological data measured on fresh wood material and modelled into anthracological data with the dendro-anthracological tools. In this way, anthracological types were defined for each wood stand, forming anthraco-typological models, which area useful for the interpretation of archaeological charcoal assemblages. Finally, an anthracological key is proposed to sort archaeological charcoal fragments in anthraco-groups before data processing. [ABSTRACT FROM AUTHOR]

Hunter-gatherers collected and used various woody species depending on the landscape, availability of plant communities, and sociocultural considerations. With extensive paleo-wetlands and groundwater-fed oases, the Atacama Desert was interspersed with riparian woodlands that provided vital resources (fuel, water, and game) at the end of the Pleistocene in areas such as the Pampa del Tamarugal (PdT) basin. We use anthracological analyses to determine the fuel management strategies of hunter-gatherer societies in this hyperarid environment and explore whether the "Principle of Least Effort" applies. First, we present the combustion qualities and characteristics of woody taxa from the Atacama and analyze possible exploitation strategies. Second, we use anthracological analyses from Quebrada Maní 12 (QM12), a late Pleistocene archaeological site (dated from 12,750 to 11,530 cal B.P.) located in the PdT basin, to show the prevalence of two woody species that were either freshly collected or gathered (very likely on purpose) from subfossil wood. Our results suggest that fuel selection strategies were based on prior knowledge of the qualities of these woody taxa and how they burned. Thus we conclude that fuel management was part of a number of social and economic decisions that allowed for effective colonization of this region. Furthermore, we stress the need for caution when using charcoal to exclusively date archaeological sites located in desert environments. [ABSTRACT FROM AUTHOR]

Abstract: A high-resolution, continuous 10,500 cal. yrs-long macroscopic charcoal record from a peat and lake sediment deposit at Storasjö, in the hemiboreal vegetation zone of southern Sweden, is presented. This record was compared with the microscopic charcoal record from the same core, and tentatively correlated with the macroscopic and microscopic charcoal records from another site (Stavsåkra), situated 30 km West of Storasjö. The charcoal records are also compared with regional climate proxy records with the aim to separate climate — from human-induced fire activity. The results suggest that the major signal of both microscopic and macroscopic charcoal records represents local fire history. The best record of local fire history was obtained from the continuous macroscopic charcoal analysis. A tentative correlation of the charcoal records between the sites indicates that most fire episodes of the early and middle Holocene are probably of regional character. Both sites exhibit three major phases of high fire activity 1) 8700–8300 BC, 2) 7250 BC to ca. 4000 BC, and 3) 750 BC to the 19th century. These three phases are separated by periods with lower or very low fire activity. This general trend is in good agreement with the pattern emerging for Europe from the analysis of the recently developed global charcoal database. Fire appears to have been controlled by climate during the early and middle Holocene and by humans during the late Holocene. Warmer and drier climate during the early and middle Holocene caused frequent and intensive fires, which suggests that natural fire activity might increase under predicted future climate scenarios. The results also suggest that fire was an important disturbance factor in the hemiboreal vegetation zone of Sweden and played an important role in the forest dynamics and characteristics of the flora and fauna of the region. [Copyright &y& Elsevier]

Abstract: In hedged landscapes, the hedge structure induces a modification of soil organization at the landscape scale and another modification of soil geometry and properties at the slope scale. In these environments, the effects of landscape structures on soil pedogenesis and properties are identified, yet the time scale on which the target processes are occurring remains unknown. The aim of this paper is to constrain the space and time changes in hedge structure, within a historical hedged landscape, in order to better quantify the dynamics of A-horizons geometry. To achieve this goal, we implemented various relative methods (soil geometry analysis, historical document analysis) and absolute methods (14C, 137Cs). Results highlight the complexity of soil spatial organization within the landscape: A-horizon geometry is clearly influenced by landscape structures, whereas deeper horizons appear not to be influenced by these structures. The explanatory factors of this current organization are not only the present topography and hedgerow network pattern, but also the position of former hedgerows. Organo-mineral horizon changes clearly post-date the establishment of the hedgerow network landscape, which has controlled topsoil horizon geometry. Since 1833, the decrease in hedgerow network density has changed the spatial distribution of soil redistributions through diffusive transport (including tillage translocation) and water erosion processes; locally, it has increased soil erosion processes with respect to the increase in uphill drainage surface areas without changing general soil organization at the landscape scale acquired over the longer term. [Copyright &y& Elsevier]