Showing papers in "Vegetation History and Archaeobotany in 2014"

Towards mapping the late Quaternary vegetation change of Europe

Abstract: The number of well-dated pollen diagrams in Europe has increased considerably over the last 30 years and many of them have been submitted to the European Pollen Database (EPD). This allows for the construction of increasingly precise maps of Holocene vegetation change across the continent. Chronological information in the EPD has been expressed in uncalibrated radiocarbon years, and most chronologies to date are based on this time scale. Here we present new chronologies for most of the datasets stored in the EPD based on calibrated radiocarbon years. Age information associated with pollen diagrams is often derived from the pollen stratigraphy itself or from other sedimentological information. We reviewed these chronological tie points and assigned uncertainties to them. The steps taken to generate the new chronologies are described and the rationale for a new classification system for age uncertainties is introduced. The resulting chronologies are fit for most continental-scale questions. They may not provide the best age model for particular sites, but may be viewed as general purpose chronologies. Taxonomic particularities of the data stored in the EPD are explained. An example is given of how the database can be queried to select samples with appropriate age control as well as the suitable taxonomic level to answer a specific research question.

Postglacial history of vegetation, human activity and lake-level changes at Jezioro Linówek in northeast Poland, based on multi-proxy data

Abstract: We present the postglacial history of vegetation, human activities and changes in lake level in the context of climate change in northeast Poland from ~14,000 cal. b.p. to the present day. The palaeoecological reconstruction is based on the results of high-resolution plant macrofossil analyses as well as records from pollen, Cladocera and radiocarbon dating. Climate fluctuations and human activity have caused many changes in vegetation development in Jezioro Linowek and in the vicinity of this lake. The Early Holocene warming that occurred at ~9500 b.c. caused an increase in Betula and the colonisation of Linowek by Potamogeton lucens, Nymphaea alba and Chara sp. At ~2300 b.c., climate cooling was accompanied by the spread of Picea abies and the appearance of Potamogeton alpinus and Nuphar pumila in the lake. The first traces of farming in the form of Cerealia pollen have been dated back to ~2100 b.c. The cultivation of Triticum began at ~250 b.c., Secale at ~a.d. 550, and Fagopyrum at ~a.d. 1720. The rapid increase in human activity at ~a.d. 1700 and the simultaneous loss of woodland is associated with the establishment of villages in the area and is expressed by the decline of tree curves. In Linowek, which was formed ~14,000 cal. b.p., three periods of high water level occurred (12000–9400, 7000–4000 and 1450 b.c.–a.d. 650), and two periods of low water level (9400–7100 and 3700–1700 b.c.). The changes of water level correspond well with other sites in central and northern Europe.

18,000 years of grassland evolution in the summer rainfall region of South Africa: evidence from Mahwaqa Mountain, KwaZulu-Natal

Abstract: A palynological and sedimentological record from the Mahwaqa Mountain in KwaZulu-Natal, South Africa, provides evidence of the vegetation dynamics in this part of the Grassland Biome during the last c. 18,000 years. The wetland is located at 1,850 m on an isolated outlier of the Ukhahlamba–Drakensberg Mountain range on an ecotone along a climatic gradient. The vegetation responded to humidity and temperature changes during the late Pleistocene and Holocene. The period c. 18,000–13,500 cal. bp is characterized by high Ericaceae and Restionaceae percentages and decreasing values of charred particles, indicating cool conditions. Around 13,500–8,500 cal. bp, Ericaceae were gradually replaced by Poaceae, signaling climate warming. Growing environmental wetness during the same time period is inferred from Phragmites-type and Cliffortia pollen percentages. Since c. 8,500 cal. bp, Cliffortia, Restionaceae, and Phragmites-type percentages have maintained low levels. Ericaceae were almost completely replaced by grasses and Asteraceae by c. 7,500 cal. bp. All indications are that warm and fluctuating moisture conditions followed until 4,600 cal. bp but they became driest between c. 4,600 and 3,500 cal. bp, when high Asteraceae, Pentzia-type and Scabiosa percentages were prominent. From c. 3,500–800 cal. bp, the increase of sedges, Aponogeton and grass pollen (including Phragmites-type) at the expense of Asteraceae pollen suggests the return of slightly more humid conditions. Since c. 1,000 cal. bp an increase of water demanding Podocarpus and Cliffortia occurred. Pine pollen indicates the recent introduction of alien plants in the 19th and 20th centuries.

Agriculturalists and pastoralists: Bronze Age economy of the Murghab alluvial fan, southern Central Asia

Abstract: Archaeological investigations of pastoral economies often emphasize exchange relations with agricultural populations, though for Bronze Age Eurasia the notion of a ubiquitous ‘pastoral realm’ has masked various forms of mixed subsistence economies. In Central Asia, there are few attempts to specifically identify the domestic crops utilized by mobile pastoralists or what they may suggest about the role of agriculture in mobile pastoral production or subsistence strategies. This study reports the macrobotanical remains from two Late/Final Bronze Age (ca. 1950–1300 bc) mobile pastoralist habitation sites in the Murghab alluvial fan region of southern Turkmenistan. We compare our results with published macrobotanical data from contemporary agricultural settlements in the Murghab region, as well as with other sites in broader prehistoric Eurasia. We find that mobile pastoralists in the Murghab utilized some of the same domestic crops as their sedentary neighbors. While the data presented here do not preclude the possibility that mobile pastoralists may have practiced some low-investment cultivation (particularly of millet), we hypothesize an economic model that places mobile pastoralists in direct contact with nearby sedentary farming communities through exchange for pre-processed grains. These results highlight one of the possible strategies of mobile pastoral subsistence in Central Asia, and are a further step toward identifying the various degrees of agricultural involvement in the conceptually outdated pastoral realm of Eurasia.

The potential role of humans in structuring the wooded landscapes of Mesolithic Ireland: a review of data and discussion of approaches

Abstract: This paper has two primary aims. Firstly, we review new data demonstrating interactions between people, plants, animals and woodlands in Mesolithic Ireland (ca. 8000–4000 cal. b.c.). This includes a synthesis of evidence from archaeological fishtraps, plant macrofossils, palynological indications of disturbance, and large mammal records. Secondly, we suggest that the potential role of humans in structuring the wooded landscape of the island of Ireland has been underestimated and is a key area for future research; Ireland may be an important case study for understanding the role of hunter-gatherers in influencing ecological relationships at the landscape scale. The new data demonstrate that existing models of the role of humans in structuring the wooded landscapes of Ireland are inadequate, and we suggest that new models are required.

Holocene climate, fire and vegetation dynamics at the treeline in the Northwestern Swiss Alps

Abstract: Treelines are expected to rise to higher elevations with climate warming; the rate and extent however are still largely unknown. Here we present the first multi-proxy palaeoecological study from the treeline in the Northwestern Swiss Alps that covers the entire Holocene. We reconstructed climate, fire and vegetation dynamics at Iffigsee, an alpine lake at 2,065 m a.s.l., by using seismic sedimentary surveys, loss on ignition, visible spectrum reflectance spectroscopy, pollen, spore, macrofossil and charcoal analyses. Afforestation with Larix decidua and tree Betula (probably B. pendula) started at ~9,800 cal. b.p., more than 1,000 years later than at similar elevations in the Central and Southern Alps, indicating cooler temperatures and/or a high seasonality. Highest biomass production and forest position of ~2,100–2,300 m a.s.l. are inferred during the Holocene Thermal Maximum from 7,000 to 5,000 cal. b.p. With the onset of pastoralism and transhumance at 6,800–6,500 cal. b.p., human impact became an important factor in the vegetation dynamics at Iffigsee. This early evidence of pastoralism is documented by the presence of grazing indicators (pollen, spores), as well as a wealth of archaeological finds at the nearby mountain pass of Schnidejoch. Human and fire impact during the Neolithic and Bronze Ages led to the establishment of pastures and facilitated the expansion of Picea abies and Alnus viridis. We expect that in mountain areas with land abandonment, the treeline will react quickly to future climate warming by shifting to higher elevations, causing drastic changes in species distribution and composition as well as severe biodiversity losses.

Challenges in the presentation and analysis of plant-macrofossil stratigraphical data

Abstract: Plant-macrofossil analysis is being increasingly used in Quaternary science, particularly palaeoecology and vegetation history. Although the techniques of macrofossil analysis are well-tried and relatively simple, the resulting data consisting of qualitative binary presences and absences, ordinal classes, and quantitative counts are not simple from the viewpoint of numerical data-analysis. This essay reviews the nature of macrofossil data and discusses the problem of zero and non-zero values. Problems in the presentation of macrofossil data are outlined and possible solutions are discussed. The handling of such data is discussed in terms of data summarisation, data analysis, and data interpretation. Newly developed numerical methods that take account of the mixed nature and the stratigraphical ordering of macrofossil data are outlined, such as (distance-based) multivariate regression trees, canonical analysis of principal coordinates, principal curves, cascade multivariate regression trees, and RLQ analysis. These and other techniques outlined have the potential to help exploit the full potential of macrofossil stratigraphical data in Quaternary palaeoecology.

The environmental and cultural contexts of the late Iron Age and medieval settlement in the Mazurian Lake District, NE Poland: combined palaeobotanical and archaeological data

Abstract: Pollen analysis of sediments from three lakes and analysis of plant macroremains including charcoal from archaeological sites in the Mazurian Lake District provide new data for the reconstruction of vegetation changes related to human activity between the 1st and 13th century ad. At that time settlements of the Bogaczewo culture (from the turn of the 1st century ad to the first part of the 5th century ad), the Olsztyn Group (second part of the 5th century ad to the 7th or beginning of the 8th century ad), and the Prussian Galinditae tribes (8th/9th–13th century ad) developed. The most intensive woodland clearing occurred between the 1st and 6th/7th century ad. Presence of Cerealia-type, Secale cereale and Cannabis-type pollen, as well as macroremains of Hordeum vulgare, S. cereale, Triticum spelta, T. cf. monococcum, T. cf. dicoccum, Avena sp. and Panicum miliaceum documented local agriculture. High Betula representation synchronous with microcharcoal occurrence suggests shifting agriculture. After forest regeneration between c. ad 650 and 1100, the area was strongly deforested due to the early medieval occupation by Prussian tribes. The archaeobotanical examination of samples taken in a cemetery and a large settlement of the Roman Iron Age revealed strong differences in the taxonomic composition of the fossil plant remains. An absolute dominance of birch charcoal in the samples from the cemetery indicates its selective use for funeral pyre construction. There is a difference between cereals found in both contexts: numerous grains of Triticum have been found in the cemetery, while in the settlement crops were represented mostly by Secale and Hordeum. Grass tubers, belonging probably to Phleum pratense, are among the particularly interesting plant remains found in the cemetery.

On the origins and spread of Olea europaea L. (olive) domestication: evidence for shape variation of olive stones at Ugarit, Late Bronze Age, Syria—a window on the Mediterranean Basin and on the westward diffusion of olive varieties

Abstract: Charred archaeological stones of Olea europaea L. (olive) from Late Bronze Age Ugarit, Syria, were analyzed with geometric morphometry and compared with a morphological differentiation model established on the basis of analyses of modern spontaneous (uncultivated) olive populations and cultivated varieties of various origins within the Mediterranean Basin. The results allow a reinterpretation of the east–west morphological diversity previously observed in wild olives. The archaeobotanical data were compared in detail to the partly geographically structured modern morphological diversity of the cultivated olive. Ancient morphotypes could be distinguished, among which one is dominant in the assemblage. Their diffusion from east to west is shown, and their time of arrival in the northwestern Mediterranean can be evaluated by comparison to archaeological material from that area. Combining morphometric and genetic data, modern reference and archaeological material also guides us in understanding the mechanisms that prevailed in the long-term agrobiodiversity of the olive.

The Iron Age in the Mrągowo Lake District, Masuria, NE Poland: the Salęt settlement microregion as an example of long-lasting human impact on vegetation

Abstract: Pollen, non-pollen palynomorphs, charcoal and geochemical analyses of sediments from Lake Salet (NE Poland) were used to reconstruct vegetation changes related to the activity of the West Balt tribes during the Iron Age, in the period between the second half of the 7th century bc and the beginning of the 10th century ad. We distinguished five phases of human impact on environment. Woodland clearing around the studied lake started at the end of the 7th century bc. The most characteristic feature of this area during the whole Iron Age was a very high representation of semi-natural Betula woodlands, which was probably linked to a shifting agriculture. This type of land use lasted for over 1,500 years, until the second half of the 9th century ad. The greatest reduction in Betula woodlands took place between cal. years 650 and 450 bc. Its regeneration took place after ca. ad 830 when human activity decreased.

The archaeobotany of long-term crop storage in northwest African communal granaries: a case study from pre-Hispanic Gran Canaria (cal. ad 1000–1500)

Abstract: Communal granaries are a widespread and very significant feature of northwest Africa. Here the first systematic archaeobotanical study of such a granary is presented, with desiccated plant macro-remains retrieved from the pre-Hispanic site of El Alamo-Acusa, Gran Canaria, Spain (cal. ad 1000–1500). While modern contamination caused by animals was evident, most plant remains found there were ancient, including cereals, pulses, cultivated fruits and wild gathered plants. Hordeum vulgare ssp. vulgare and Ficus carica were the most common taxa, which appear to have been the two main staple foods for the pre-Hispanic population. The high frequencies of chaff and other plant residues indicate that crops were stored unprocessed. Most food plants had been eaten by insects and other animals, and only unpalatable parts were present. Remains of Sitophilus granarius (grain weevil) were common in the samples, suggesting problems of insect pests during long-term storage. In addition, we have identified leaves of cf. Laurus novocanariensis, which may have been used as an insect repellent.

Stable carbon isotope analysis as a crop management indicator at Arslantepe (Malatya, Turkey) during the Late Chalcolithic and Early Bronze Age

Abstract: In Near Eastern archaeology, studies on crop management during the early stages of civilisation have been based on cuneiform texts and only recently have geoarchaeological surveys and archaeobotanical studies tried to identify agricultural practices. Nevertheless, direct evidence for irrigation and water management is very rare and difficult to interpret. New possibilities for analysing these ways of management have been provided by stable carbon isotope analysis of ancient crops. In this study carbon isotope discrimination (Δ13C) was performed to assess the growing conditions of fossil cereal grains. Charred grains of emmer and barley recovered from the same site, Arslantepe in eastern Anatolia, over a 1,000 years long continuous sequence during the third millennium b.c. have been analysed and compared. The variation in water availability during grain filling, estimated by Δ13C, can be attributed to climate change and/or human practices. Distinguishing exactly which is to blame is complex but essential in reconstructing specific management practices. Variations in the 13C/12C ratio suggest that barley and emmer grew under different water regimes. In particular, a different management system was adopted between 3000 and 2800 cal. b.c. when emmer was sustained by human-induced water supply, whereas the more resistant barley was rain-fed and possibly assigned to more marginal terrains. Our results are compared with the stable carbon isotope data available for other Near Eastern sites. Emmer and barley records are also compared with deciduous oak Δ13C from Arslantepe in order to better understand the influence of environmental factors, climate and human impact.

Revisiting tree-migration rates: Abies alba (Mill.), a case study

Abstract: At northern temperate latitudes trees have adjusted their ranges substantially in response to changing climates during the Holocene. Results from dispersal model simulations suggest that postglacial migration rates may have been over-estimated from fossil pollen data. As a contribution to this debate, we infer the migration rates of Abies alba (Mill.), silver fir, as a case-study species, by using a spatially explicit approach based on fossil pollen but taking into account its modern genetic diversity pattern. Maximum estimates of migration rates from fossil pollen data alone are higher than 700 m yr−1 during the Holocene. Considering the potential refugia as suggested from all the fossil data but restricting the area over which silver fir expanded from each glacial refugium using data on the current haplotype distribution, the estimated maximum migration rates of silver fir are less than 250 m yr−1. Genetic information may allow for (1) the exclusion of those refugial areas where the species may have survived during the last glacial period but from which it did not spread or spread only very locally and (2) the delineation of the areas over which the species spread from each glacial refugium. The estimated rates in the present study are generally consistent with rates suggested from modelling approaches. This study shows that integrating fossil pollen records can improve simulations of dispersal processes and, thus, allow for better predictions of future changes in tree species’ ranges.

Optimal counting limit for fungal spore abundance estimation using Sporormiella as a case study

Abstract: The use of non-pollen palynomorphs, and among them spores of coprophilous fungi, has become greatly important in palaeoecological studies. Particularly, the genus Sporormiella has been demonstrated to be the most valuable proxy for the presence of wild and domestic herbivores. This genus could also be used to determine livestock density and reconstruct pastoral pressure during the Holocene. Non-standard counting methods have been established to determine coprophilous fungal spore abundance in sediments. Moreover, these analyses are faced with the recurrent problem of setting the minimum counting sum as small as possible to save time. We researched the reliability of Sporormiella concentration estimates based on different counting sums, using low to high count samples. Box-plots indicate that the variability of inferred Sporormiella concentrations decreases progressively with increasing sums. Statistical comparisons show that the means of box-plots became stabilised after the counts have reached 300–350 exotic marker grains. Moreover, a count of 300–350 exotic marker grains is sufficient to produce a Sporormiella concentration estimate, whatever the amount. Finally, we propose that this counting limit is valid for other fungal spores as well.

Palynological richness and evenness: insights from the taxa accumulation curve

Abstract: Palynology provides the opportunity to make inferences on changes in diversity of terrestrial vegetation over long time scales. The often coarse taxonomic level achievable in pollen analysis, differences in pollen production and dispersal, and the lack of pollen source boundaries hamper the application of diversity indices to palynology. Palynological richness, the number of pollen types at a constant pollen count, is the most robust and widely used diversity indicator for pollen data. However, this index is also influenced by the abundance distribution of pollen types in sediments. In particular, where the index is calculated by rarefaction analysis, information on taxonomic richness at low abundance may be lost. Here we explore information that can be extracted from the accumulation of taxa over consecutive samples. The log-transformed taxa accumulation curve can be broken up into linear sections with different slope and intersect parameters, describing the accumulation of new taxa within the section. The breaking points may indicate changes in the species pool or in the abundance of high versus low pollen producers. Testing this concept on three pollen diagrams from different landscapes, we find that the break points in the taxa accumulation curves provide convenient zones for identifying changes in richness and evenness. The linear regressions over consecutive samples can be used to inter- and extrapolate to low or extremely high pollen counts, indicating evenness and richness in taxonomic composition within these zones. An evenness indicator, based on the rank-order-abundance is used to assist in the evaluation of the results and the interpretation of the fossil records. Two central European pollen diagrams show major changes in the taxa accumulation curves for the Lateglacial period and the time of human induced land-use changes, while they do not indicate strong changes in the species pool with the onset of the Holocene. In contrast, a central Swedish pollen diagram shows comparatively little change, but high richness during the early Holocene forest establishment. Evenness and palynological richness are related for most periods in the three diagrams, however, sections before forest establishment and after forest clearance show high evenness, which is not necessarily accompanied by high palynological richness, encouraging efforts to separate the two.

Neolithic cultivation of tetraploid free threshing wheat in Denmark and Northern Germany: implications for crop diversity and societal dynamics of the Funnel Beaker Culture

Abstract: For the first time, rachis fragments of tetraploid free threshing wheat were discovered for the Early Neolithic of the North European Plain, proving its cultivation by farmers of the Neolithic Funnel Beaker North group. A compilation of finds of free threshing wheat for Northern Europe based on a temporal resolution of Funnel Beaker sub-periods shows the importance of free threshing wheat—independent of genomic constitution—in the Early Neolithic Funnel Beaker crop assemblage. Based on this new evidence, we assume that the crop assemblages of the first farmers on the North European Plain consisted of three main cereals: emmer, barley and free threshing wheat. Both the new finds and the compilation of free threshing wheat finds support the scenario of a chronological separation of different agricultural systems that were implemented within different Funnel Beaker phases. Furthermore, the evidence for tetraploid free threshing wheat shows that the tradition of early Funnel Beaker groups is linked to southwestern agricultural developments, for example, of the Michelsberg group.

The forest people: landscape and firewood use in the Araruama region, southeastern Brazil, during the late Holocene

Abstract: The site of Morro Grande, situated in the Araruama region, southeastern Brazil (22o47′07″S, 42o21′49″W), is in the Atlantic rainforest phytogeographical domain. It is attributed to proto-Tupinamba agriculturalist and ceramicist populations, recognized by their typical polychrome ceramics. Four periods of occupation were identified at this site: (1) 3,220–2,840 cal b.p.; (2) 3,000–2,150 cal b.p.; (3) 1,820–1,390 cal b.p.; and (4) c. 750 cal. b.p. Analysis of 3,908 charcoal fragments from the three earlier periods has allowed the identification of 78 taxa and 29 plant families. This work demonstrates the permanence of the Atlantic rainforest in the region between 3,220 and 1,390 cal b.p., confirming previous palaeoenvironmental studies in southeastern and southern Brazil. The existence of mature forests is demonstrated; however, firewood was collected mainly from secondary vegetation, probably in the area surrounding the settlement or from cultivated land. These results provide further evidence of human influence on Neotropical rainforests. Creation of secondary environments, however, did not result in irreversible damage to local biodiversity, since the forest tended to regenerate after the clearings were abandoned. Analysis of charcoal concentrated in features allowed the identification of ritual funerary hearths, as well as of a probable specialized feature for firing ceramics. This evidence affords new perspectives for the archaeological interpretation of the funerary ritual and way of life of proto-Tupinamba people.

Forage quality of leaf-fodder from the main broad-leaved woody species and its possible consequences for the Holocene development of forest vegetation in Central Europe

Abstract: Leaf-hay was the principal winter feed of livestock from the Neolithic until the first archaeological records of scythes dated to the Iron Age (700–0 b.c.). Despite the use of meadow hay, leaf-fodder remained an important winter supplement until the present. Archaeological evidence lists Quercus, Tilia, Ulmus, Acer, Fraxinus and Corylus as woody species harvested for leaf-fodder, while Fagus, Populus or Carpinus were rarely used. The aim of our study was to test whether the use of listed woody species followed the pattern of their forage quality (syn. nutritive value). In late May 2012, we collected leaf biomass at four localities in the Czech Republic and determined concentrations of N, P, K, Ca, Mg, neutral- and acid-detergent fibre and lignin. Species with leaves of low forage quality were Carpinus betulus, Fagus sylvatica and Quercus robur, species with leaves of intermediate quality were Corylus avellana and Populus tremula and species with leaves of high quality were Ulmus glabra, Fraxinus excelsior, Tilia cordata and Acer platanoides. Selective browsing and harvesting of high quality species Acer, Fraxinus, Tilia and Ulmus thus probably supported their decline in the Bronze and Iron ages and supported the expansion of Carpinus and Fagus. Our results indicate that our ancestors’ practice of exploiting woody species as leaf-hay for winter fodder followed their nutritive value.

The history of early cereal cultivation in northernmost Fennoscandia as indicated by palynological research

Abstract: The age of the introduction of cereal cultivation in northern Europe has long been debated by researchers from many disciplines, in particular archaeology and palaeoecology. Over the past 40 years extensive palynological data have been collected concerning pre-industrial land use in northern Fennoscandia. This paper reviews palynological studies that include records of fossil cereal pollen from northernmost Sweden, Finland and Norway at latitudes north of 63°N. The geographical extent of known early cultivation sites is constantly expanding, with more than 100 records of cereal pollen pre-dating ad 1700. The oldest records of scattered cereal pollen derive from Neolithic times. Periods of continuous cultivation, indicated by cereal pollen recorded recurrently in the sediment profiles, derive from the Late Neolithic and Early Bronze Age. Collectively, the reviewed pollen records indicate that cereal cultivation was first introduced into areas close to the coast and later to the interior, and that it may have been practiced locally long before sedentary settlements based on intensive cultivation were established during medieval times. The data do not indicate a latitudinal spread of cultivation from south to north. However, methodological problems relating to pollen morphology of cereals, site characteristics and lack of connections to archaeologically excavated sites imply that the value of many early cereal pollen finds remains unclear. To increase our understanding of the context in which cereal cultivation was introduced in northernmost Fennoscandia, multidisciplinary studies integrating palaeoecology, archaeology and history are needed.

Reconstruction of Holocene vegetation, tree cover dynamics and human disturbances in central European Russia, using pollen and satellite data sets

Abstract: This paper presents an assessment of Holocene tree cover densities and forest disturbance in European Russia using the best-modern-analogue (BMA) technique of quantitative reconstruction and an innovative approach, which combines modern pollen datasets with remotely sensed data from moderate-resolution imaging spectroradiometer satellite images. The test of the accuracy of the applied method using a database of 450 sets of surface pollen assemblages shows that it can reproduce present day characteristics of woody cover in Europe correctly (R 2 = 0.57, standard error = 10.8 %), and it is sufficient for reconstruction of major changes of woodland vegetation in the past. Application of the BMA technique to fossil pollen data from two key regions in the central part of European Russia demonstrates that changes in regional woody cover are useful for the reconstruction of prehistoric human disturbance.

Contribution to the reconstruction of central European fire history, based on the soil charcoal analysis of study sites in northern and central Germany

Abstract: Fire caused by humans played an important role in prehistoric clearance of woodland, which was a prerequisite for the rise of agriculture since at least the Neolithic revolution. Therefore, reconstructed fire history provides insights into the spread of agriculture. However, for central Europe, the past fire regime is still poorly known. Thus, to help to fill this gap, fire history has been investigated using data relevant at a local scale, which is the scale of woodland clearance processes according to local human practices. For this purpose, soil/soil sediment charcoal analysis has been conducted at four sites in northern Germany and five in central Germany. At each site, four to nine sequences of soil/soil sediment were excavated, described in the field and sampled. The sampled material has been differentiated by soil horizons formed in situ and colluvial sediments. The charcoal content of both types of sampled material was quantified and some of it was taxonomically analysed. Chronological information was obtained by radiocarbon dating 73 single charcoal pieces that had previously been identified taxonomically. Such data sets have permitted us to identify a minimum number of fire events for every site, which had burnt various types of woodlands and at different chronological phases. Based on the local scale data, regional trends were identified. Charcoals from the late Pleistocene and early Holocene derived from conifers only, and these most probably indicate wildfire events in flammable woodlands. Charcoals dated to the mid and late Holocene derived predominantly from broad-leaved trees probably resulting from human-ignited fires in weakly flammable woodlands. The calculated minimum fire frequency indicates an increase in fire occurrences during the Holocene following the phases of cultural human development. This supports the importance of human-made fire in northern central Europe during the Holocene. Such minimum fire frequency appears much higher during the iron age and the middle ages, but not before. This fits with the general statement of regional woodland loss and landscape opening relatively recently, during the late Holocene.

The potential of stomata analysis in conifers to estimate presence of conifer trees: examples from the Alps

Abstract: To estimate whether or not a plant taxon found in the fossil record was locally present may be difficult if only pollen is analyzed. Plant macrofossils, in contrast, provide a clear indication of a taxon’s local presence, although in some lake sediments or peats, macrofossils may be rare or degraded. For conifers, the stomata found on pollen slides are derived from needles and thus provide a valuable proxy for local presence and they can be identified to genus level. From previously published studies, a transect across the Alps based on 13 sites is presented. For basal samples in sandy silt above the till with high pollen values of Pinus, for example, we may distinguish pine pollen from distant sources (samples with no stomata), from reworked pollen (samples with stomata present). The first apparent local presence of most conifer genera based on stomata often but not always occurs together with the phase of rapid pollen increase (rational limit). An exception is Larix, with its annual deposition of needles and heavy poorly dispersed pollen, for it often shows the first stomata earlier, at the empirical pollen limit. The decline and potential local extinction of a conifer can sometimes be shown in the stomata record. The decline may have been caused by climatic change, competition, or human impact. In situations where conifers form the timberline, the stomata record may indicate timberline fluctuations. In the discussion of immigration or migration of taxa we advocate the use of the cautious term “apparent local presence” to include some uncertainties. Absence of a taxon is impossible to prove.

Revisiting and modelling the woodland farming system of the early Neolithic Linear Pottery Culture (LBK), 5600–4900 b.c.

Abstract: This article presents the conception and the conceptual results of a modelling representation of the farming systems of the Linearbandkeramik Culture (LBK). Assuming that there were permanent fields (PF) then, we suggest four ways that support the sustainability of such a farming system over time: a generalized pollarding and coppicing of trees to increase the productivity of woodland areas for foddering more livestock, which itself can then provide more manure for the fields, a generalized use of pulses grown together with cereals during the same cropping season, thereby reducing the needs for manure. Along with assumptions limiting bias on village and family organizations, the conceptual model which we propose for human environment in the LBK aims to be sustainable for long periods and can thereby overcome doubts about the PFs hypothesis for the LBK farming system. Thanks to a reconstruction of the climate of western Europe and the consequent vegetation pattern and productivity arising from it, we propose a protocol of experiments and validation procedures for both testing the PFs hypothesis and defining its eco-geographical area.

The domestication of Helianthus annuus L. (sunflower)

Abstract: All modern domesticated sunflowers can be traced to a single center of domestication in the interior mid-latitudes of eastern North America. The sunflower achenes and kernels recovered from six eastern North American sites predating 3000 b.p. that document the early history of this important crop plant are reanalyzed, and two major difficulties in the interpretation of archaeological sunflower specimens are addressed. First, achenes and kernels obtained from a modern wild sunflower population included in a prior genetic study because of its minimal likelihood for crop-wild gene flow, and its close genetic relationship to domesticated sunflowers, provide a new and more tightly drawn basis of comparison for distinguishing between wild and domesticated achene and kernel specimens recovered from archaeological contexts. Second, achenes and kernels from this modern wild baseline population were carbonized, allowing a direct comparison between carbonized archaeological specimens and a carbonized modern wild reference class, thereby avoiding the need for the various problematic shrinkage correction conversion formulas that have been employed over the past half century. The need for further research on museum collections is underscored, and new research directions are identified.

Living on the good soil: relationships between soils, vegetation and human settlement during the late Allerød period in Denmark

Abstract: The immigration of woody plants, especially Betula (tree birch), is examined in relation to geomorphological regions in a compilation of Late-glacial plant macrofossil records from Denmark. The immigration of trees led to a large ecological transformation of the landscape and had a major effect on the flora and fauna available to Palaeolithic people. We show that soil type was a controlling factor in the development of vegetation during the Allerod and Younger Dryas periods. Following the first immigration of trees during the Allerod period, woods became established in the eastern part of Denmark, where ice advances from the Baltic had deposited calcareous and clayey sediments. The western and northern parts of Denmark that are characterised by more sandy and non-calcareous sediments remained treeless throughout the whole Late-glacial period. Finds from the Bromme Culture are concentrated in the region which was wooded, suggesting that the regional variable environment allowed local adaptations using the diverse resources available.

Erratum to: Botanical off-site and on-site data as indicators of different land use systems: a discussion with examples from Southwest Germany

Abstract: Off-site pollen data as well as onsite plant macrofossil data from Southwest Germany enable the distinguishing of three main phases of agricultural land use history. The last phase, here simplified called the “Extensive ard phase”, had already started in the Bronze Age and ends in the 19th century a.d. It is characterized by extensive land management, permanent fields with short fallow phases, ploughing, the use of animal dung as fertilizer, and grazed woodlands. The first phase, comprising the Old and Middle Neolithic, is characterized by hoe-farming only on very fertile soils and a very restricted set of crops. For the second phase, comprising the Young, Late and Final Neolithic, a slash-and-burn-like agricultural system is most probable. During the Late and Final Neolithic, this cultivation system with fire use and shifting fields was gradually practised on permanent fields and was modified, leading finally to the “Extensive ard” land use system with fertilizer and ploughing instead of burning.

Intensive agriculture and land use at Roman Gordion, central Turkey

Abstract: Few archaeobotanical studies of Roman agricultural practices and their environmental impact in Anatolia (modern Turkey) have been published. New data from Roman levels at Gordion, a multi-period urban centre in central Anatolia, indicate that free-threshing wheat, most likely Triticum aestivum (bread wheat), was the focus of agricultural practice, in contrast to earlier periods when a more diverse agricultural system included greater amounts of barley and pulses. Evidence for increased levels of irrigation and wood fuel use relative to dung, along with regional overgrazing, provide further evidence for significant change in land-use practices during the Roman period. The emphasis on T. aestivum cultivation coupled with extensive grazing had significant environmental implications, leading to severe overgrazing and soil erosion on a regional scale. Historical sources and limited data from other Roman period sites suggest that similar patterns of agriculture may have been practiced across central Anatolia during the Roman period. We propose that this may have been due to externally imposed demands for taxation or military tribute in the form of wheat, and conclude that these demands led to the adoption of an unsustainable agricultural system at Gordion.

Vegetation history of chernozems in the Czech Republic

Abstract: Chernozem is a soil type which can be characterised by a thick dark surface horizon, which consists of organic matter and tends to change into a carbonate horizon or more often into a loess horizon. Chernozem is defined as a zonal soil that has developed under steppe vegetation in a dry continental climate. Nevertheless, chernozems can also be found in central Europe, where there are no climatic conditions for the existence of any steppe. This study is focused on the vegetational aspect of the pedogenesis of chernozems. We have examined three sorts of chernozems for their charcoal and pedological characteristics: the functional chernozems, the chernozems buried in Holocene material and the chernozems buried in Pleistocene material. The charcoal examination has proved the presence of woodland taxa in the areas of chernozems at different periods of time. The results of this study reveal that the high stability of soil organic matter has caused the persistence of chernozems in the areas with prevalent woodland vegetation.

Tree taxa immigration to the eastern Baltic region, southeastern sector of Scandinavian glaciation during the Late-glacial period (14,500–11,700 cal. b.p.)

Abstract: The eastern Baltic region is situated in the southeastern part of the area which was covered by the last Scandinavian glaciation. Four well-dated sediment profiles from sites distributed along a ~330-km north–south transect were analysed for their macrofossil contents. The immigration of tree taxa during the Late-glacial (LG) period, which was the time of environmental change from tundra to woodland in previously glaciated areas, can be determined from these data. The pioneer vegetation in the study area was treeless dwarf shrub tundra with various dominant taxa. The so-called Allerod hemispheric warming permitted the Post-glacial immigration of trees into the southern part of the eastern Baltic region; however, these most probably disappeared during the following cold period, the Younger Dryas/GS-1. The local presence of Betula sect. Albae, Pinus sylvestris, Populus tremula and Picea abies during the LG period in the southern part of the region was confirmed. The northern part of the area presumably remained treeless for the entire LG period. Therefore, until the beginning of the Holocene, the tree line in the eastern Baltic region did not reach beyond 58°N.

The first archaeobotanical evidence of Spinacia oleracea L. (spinach) in late 12th–mid 13th century a.d. France

Abstract: Macroscopic charred remains of Spinacia oleracea L. (Amaranthaceae) have been found in the Pyrenean village of Montaillou, France, in several contexts of a house dated to the end 12th–mid 13th century a.d. This is the first archaeobotanical record of this vegetable in France and the earliest European archaeobotanical material so far found. The paper presents the morphological criteria used for identifying the charred remains of the species. After a review of archaeobotanical finds in Europe, hypotheses on the economic status of this vegetable, which is unknown as a wild plant in Europe, are discussed with reference to medieval written and illuminated sources and to archaeological deposits. It appears that Spinacia was first introduced into France from Moorish Spain where it was cultivated at least since the 11th century. The French evidence of Spinacia thus represents a milestone in the history and geographic diffusion of this vegetable into temperate Europe.