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A comprehensive study has been launched in the medieval fortress of Carcassonne involving a cooperation between the universities of Umeå and Rennes, and the research institute of IRSTEA of Montpellier. This study aims to combine several spectroscopic techniques in order to resolve archaeological problems related to which raw materials were used during the city wall construction, and also to improve our understanding of the different phases of construction and use of the city walls. This study was also used for elucidating the different qualities and weak points of the applied field methods.

The middle of the first millennium AD in Sweden witnessed significant changes in the archaeological record, prompting various discussions about the underlying causes. This paper reviews the research developments surrounding the global climate cooling, which was caused by severe volcanic eruptions in AD 536/540 and is referred to as the Late Antique Little Ice Age or Fimbulwinter, and its potential impacts, with a specific focus on Swedish Iron Age societies, drawing upon published climatic and archaeological data. Furthermore, it discusses the research gaps that impede a comprehensive understanding of the potential relationship between the AD 536/540 event and socioeconomic changes in Iron Age Sweden. Additionally, it suggests that isotopic analysis will offer additional insights and help bridge the research gap.

This article reports on a new project to investigate the activities of early Homo sapiens in the area of the Chotts ‘megalake’ in southernTunisia. Excavations in 2015 and 2019 at Oued el Akarit revealed one of a number of Middle Stone Age (MSA) horizons near the topof a long sequence of Upper Pleistocene deposits. The site identified as Oued el Akarit (Sondage 8) consists of lithic artefacts, bone fragmentsof large ungulates and pieces of ostrich eggshell. Many of the objects are burnt. Excavation of about nine square metres revealed thatthese were associated with a lightly trampled and combusted occupation surface. Amongst the identified artefacts were Levallois flakes someof which could be refitted, thereby indicating the generally undisturbed nature of the occupation. The lithic finds also included side scrapersand other tools diagnostic of the MSA but significantly no bifacial or tanged tools. OSL (Optically Stimulated Luminescence) dating of thesediments and AMS (Accelerator Mass Spectrometry) radiocarbon dating of ostrich eggshell have produced uncalibrated age determinationsin the range 37,000–40,000 years ago, one of the youngest ages for MSA sites in the region. This is the first example of a securely dated laterMSA occupation in a riparian environment in south-eastern Tunisia

Despite a growing body of evidence concerning accelerated organic degradation at archaeological sites, there have been few follow-up investigations to examine the status of the remaining archaeological materials in the ground. To address the question of archaeo-organic preservation, we revisited the Swedish, Mesolithic key-site Agerod and could show that the bone material had been subjected to an accelerated deterioration during the last 75 years, which had destroyed the bones in the areas where they had previously been best preserved. To understand why this has happened and to quantify and qualify the extent of the organic degradation, we here analyse the soil chemistry, bone histology, collagen preservation and palaeobotany at the site. Our results show that the soil at Agerod is losing, or has already lost, its preservative and buffering qualities, and that pH-values in the still wet areas of the site have dropped to levels where no bone preservation is possible. Our results suggest that this acidification process is enhanced by the release of sulphuric acid as pyrite in the bones oxidizes. While we are still able to find well-preserved palaeobotanical remains, they are also starting to corrode through re-introduced oxygen into the archaeological layers. While some areas of the site have been more protected through redeposited soil on top of the archaeological layers, all areas of Agerod are rapidly deteriorating. Lastly, while it is still possible to perform molecular analyses on the best-preserved bones from the most protected areas, this opportunity will likely be lost within a few decades. In conclusion, we find that if we, as a society, wish to keep this valuable climatic, environmental and cultural archive, both at Agerod and elsewhere, the time to act is now and if we wait we will soon be in a situation where this record will be irretrievably lost forever.

The Environmental Archaeology Lab was contracted in June 2000 to carry out palaeoenvironmental analyses on samples from the Kaupang excavation in Southern Norway. Excavation was carried out during that summer, and Pat Wagner (Sheffield University) was employed by the excavators to supervise initial sampling and teach the sampling and field processing methods. The sampled features included waterlogged deposits interpreted as wells and latrines, and deposits from pits ofunknown function. Fossil preservation varied considerably, being both a function of modern conditions and the hydrological history of the deposit, and one cannot guarantee that all material sare equally preserved.

A total of 15 soil samples were submitted to the lab, all of which were to undergo macrofossil analysis, and 6 of which were, in addition, to be analysed with respect to their fossil insect assemblages. As a matter of routine all samples underwent rudimentary soil chemistry analyses. Table 1 summarises the samples and the analyses performed upon them. In addition to the soilsamples received, several jars of test material floated on site were included, these were cursorily examined as a control to the soil samples, i.e. their faunas were checked against the appropriate sample to see whether any extra species were present in the jars. These samples are not listed in the results as the faunas were too small to be of real analytical value.

Environmental change has a human dimension, and has had so for at least the last 10 000 years. The prehistoric impact of people on the Arctic landscape has occasionally left visible traces, such as house and field structures. More often than not, however, the only evidence available is at the microscopic or geochemical level, such as fossil insect and seed assemblages or changes in the physical and chemical properties of soils and sediments. These records are the subject of SEAD, a multidisciplinary database and software project currently underway at Umeå University, Sweden, which aims to create an online database and set of tools for investigating these traces, as part of an international research infrastructure for palaeoecology and environmental archaeology.

A total of 322 bulk samples, 267 bulk subsamples and 1632 survey samples from the excavation of Iron Age settlements at Ørland, Vik, Sør-Trondelag, were analysed at the Environmental Archaeology Laboratory (MAL) at Umeå University. The overall aim of these analyses was to look for evidence which could help identify possible prehistoric activity areas, understand building functions and divisions, and shed light on land management around the farmsteads.

Environmental archaeology is a complex mix of empirical analysis and qualitative interpretation.It is increasingly data science oriented, and databases and online resources are becoming increasinglyimportant in large scale synthesis research on changes in climate, environments and human activities.Research funders, journals and universities place much emphasis on the use of data repositories toensure transparency and reusability in the research process. Although these are important, researchersthemselves, however, may have more use for research databases which are oriented more towardsadvanced querying and exploratory data analysis than conforming to archiving standards. This paperexplores the pros and cons of these different approaches. It also discusses and problematizes somekey concepts in research data management, including the definitions of data and metadata, along withthe FAIR principles. Research examples are provided from a broad field of environmental archaeologyand palaeoecology. In contrast to most publications, the developer’s perspective is also included, anda worked example using the Strategic Environmental Archaeology Database (SEAD) to investigate fossilbeetle data demonstrates the implementation of some of this in the real world. This example may befollowed online using the SEAD browser, and all described data downloaded from there. After providingboth encouragement and warnings on the use of digital resources for synthesis research, some suggestionsare made for moving forward.

Sediment micromorphology, chemistry and magnetic susceptibility of basin edge deposits at the small, mid-altitude peat site of Lago di Bargone, eastern Liguria, Italy, is compared with a full Holocene palynological sequence and radiocarbon dates from the central part of the peat bog. Micromorphology and MS550 results show that Neolithic to Copper Age forest disturbances and clearings as inferred  from the pollen diagrams, occurred during a period of lower water-tables and intermittent drying out of the basin edge deposits. Extensive deforestation and expansion of heath and rassland during the Iron Age and Roman periods is associated with increases in soil erosion and in micromorphological indications of burning. It is argued that the very fine size range of the charred fragments seen in thin sections and the seeming absence of charcoal of coarser size range suggest a system of light, controlled burning, possibly akin to the local tradition of using fire to control weeds and to encourage new grass and herbaceous growth, and not local forest clearance by fire. Micromorphology of the late-Holocene peat contains herbivore dung possibly indicating the use of the site as a watering hole by domesticated stock. The overlying colluvium displays evidence of deep-seated erosion of the local soils and geology which is most likely to have been associated with local mining activities.

Commercial digital cameras can be converted into a tool for NIR field multivariate imaging. Results obtained using such a tool are far less sophisticated than those obtained by NIR spectrometers or hyperspectral imagers but they may often be useful enough for making quick conclusions during field work.

Principal Component Analysis (PCA) is a multivariate exploratory analysis method, useful to separate systematic variation from noise. It allows to define a space of reduced dimensions that preserves the relevant information of the original data and allows visualization of objects (scores) and variables (loadings). PCA requires multivariate data, meaning many variables measured on many objects. Data, vectors and matrices are defined and a short summary of necessary linear algebra is given. Purely mathematical almost identical definitions of PCA and Singular Value Decomposition (SVD) are shown, but in chemometrics, PCA always has a residual and a number of meaningful components, the rank. This leads to a discussion of numerical and visual diagnostics for finding the rank and checking the residual. The visualization of scores and loadings is introduced by means of two small examples. Data preprocessing is also given consideration.

The concept of a hyperspectral image and the different technical steps of acquiring one are described. This includes sampling, illumination, camera calibration, and image file recording. This enables the powerful combination of being able to combine the traditional image with nonvisible chemical information and to geographically relate these types of information to each other. Hyperspectral imaging produces large data sets with geometrical-georeferenced and spectral information. A technique such as principal component analysis (PCA) produces a subset of images with the information concentrated in a few graphs and noise left out. Interactive analysis of image and scatter plots allows cleaning, and on the cleaned images a new PCA or other multivariate method can be used, creating principal component images containing the relevant information. Using this approach, latent clusters can be detected that are not evident in the initial stage of analysis. There is a large aspect of data mining involved in hyperspectral imaging analysis, which means that visual inspection and interactive brushing is one way of approaching an image with an abundance of complex information.

The aim of this article is to describe a methodology for defining functional spaces within south Scandinavian Iron Age longhouses using a multiproxy application of archaeobotanical (carbonised plant macrofossil), geochemical (phosphate, loss on ignition) and geophysical (magnetic susceptibility) analyses. The applicability of the methods is illustrated by two case studies from the site of Gedved Vest, eastern Jutland, Denmark. The approach is described and evaluated from an archaeobotanical perspective, discussing its possible implications for interpretation of carbonised plant assemblages from Iron Age settlement contexts. Possible implications to archaeology beyond the scope of archaeobotany are also discussed

This paper describes analyses for understanding the general use of space on two Early Iron Age house sites on the site of Sønderris in South-West Jutland (South Scandinavia). The main method consists of the geoarchaeological techniques of soil P analysis by citric acid extraction, low frequency magnetic susceptibility analysis, and measurement of the soils organic content by loss-on-ignition. The results of these analyses are, moreover, interpreted alongside artefact distribution data, data on the dispersal of plant macrofossils, and an evaluation of the architectural details of the sites.

At both house sites, the geoarchaeological data shows patterning indicative of human activities. The main achievements are inference of outdoor areas which may have contained pyres or kilns, delineation of yard spaces with refuse deposition, and the characterisation of functional aspects of two small outbuildings. In general, the geoarchaeological results are consistent with the inferences attained from non-geoarchaeological sources. A notable exception is that few clear traces of stalling were identified in the geoarchaeological record, despite the presence of animal booth partition walls indicating the presence of byres in the longhouses. Possible reasons for this are discussed.

Overall, this study demonstrates the continued usefulness of long-established geoarchaeological methods for gaining insights about the nature, extent, and orientation of activities on prehistoric house sites. A key take-away from the study is that the potential of any individual method for reading activities (geoarchaeological or otherwise), increases when several techniques with overlapping, but not identical, scope for inferring activities are integrated. The resulting multiproxy analysis is, as a whole, more useful than the sum of its constituent parts.

In the nineteenth century, numerous settlements were established in the alpine region of Fennoscandia (the Scandes), an area that later became a major international scene for Arctic research. Here we raise awareness of this era and show that earthworm-driven bioturbation in “pristine” soils around contemporary Arctic research infrastructure is caused by soil fauna left behind during early land use. We use soil preserved under an alpine settlement to highlight that soils were not bioturbated when the first house was built at a site where bioturbation is now widespread. A review of archived material with unique site-specific chronology constrained the onset of bioturbation to the post-1871 era. Our results suggest that small-scale land use introduced earthworms that now thrive far beyond the realms of former cultivated fields. The legacy of soil fauna from this example of “ecological imperialism” still lingers and should be considered when studying soils of the Scandes.