1. |
- Sim, Thomas G., et al.
(author)
-
Regional variability in peatland burning at mid-to high-latitudes during the Holocene
- 2023
-
In: Quaternary Science Reviews. - : Elsevier. - 0277-3791 .- 1873-457X. ; 305
-
Journal article (peer-reviewed)abstract
- Northern peatlands store globally-important amounts of carbon in the form of partly decomposed plant detritus. Drying associated with climate and land-use change may lead to increased fire frequency and severity in peatlands and the rapid loss of carbon to the atmosphere. However, our understanding of the patterns and drivers of peatland burning on an appropriate decadal to millennial timescale relies heavily on individual site-based reconstructions. For the first time, we synthesise peatland macrocharcoal re-cords from across North America, Europe, and Patagonia to reveal regional variation in peatland burning during the Holocene. We used an existing database of proximal sedimentary charcoal to represent regional burning trends in the wider landscape for each region. Long-term trends in peatland burning appear to be largely climate driven, with human activities likely having an increasing influence in the late Holocene. Warmer conditions during the Holocene Thermal Maximum (similar to 9e6 cal. ka BP) were associated with greater peatland burning in North America's Atlantic coast, southern Scandinavia and the Baltics, and Patagonia. Since the Little Ice Age, peatland burning has declined across North America and in some areas of Europe. This decline is mirrored by a decrease in wider landscape burning in some, but not all sub-regions, linked to fire-suppression policies, and landscape fragmentation caused by agricultural expansion. Peatlands demonstrate lower susceptibility to burning than the wider landscape in several instances, probably because of autogenic processes that maintain high levels of near-surface wetness even during drought. Nonetheless, widespread drying and degradation of peatlands, particularly in Europe, has likely increased their vulnerability to burning in recent centuries. Consequently, peatland restoration efforts are important to mitigate the risk of peatland fire under a changing climate. Finally, we make recommendations for future research to improve our understanding of the controls on peatland fires.(c) 2023 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).
|
|
2. |
- Abraham, Vojtech, et al.
(author)
-
Patterns in recent and Holocene pollen accumulation rates across Europe - the Pollen Monitoring Programme Database as a tool for vegetation reconstruction
- 2021
-
In: Biogeosciences. - : Copernicus GmbH. - 1726-4170 .- 1726-4189. ; 18:15, s. 4511-4534
-
Journal article (peer-reviewed)abstract
- The collection of modern, spatially extensive pollen data is important for the interpretation of fossil pollen assemblages and the reconstruction of past vegetation communities in space and time. Modern datasets are readily available for percentage data but lacking for pollen accumulation rates (PARs). Filling this gap has been the motivation of the pollen monitoring network, whose contributors monitored pollen deposition in modified Tauber traps for several years or decades across Europe. Here we present this monitoring dataset consisting of 351 trap locations with a total of 2742 annual samples covering the period from 1981 to 2017. This dataset shows that total PAR is influenced by forest cover and climate parameters, which determine pollen productivity and correlate with latitude. Treeless vegetation produced PAR values of at least 140 grains cm(-2) yr(-1). Tree PAR increased by at least 400 grains cm(-2) yr(-1) with each 10% increase in forest cover. Pollen traps situated beyond 200 km of the distribution of a given tree species still collect occasional pollen grains of that species. The threshold of this long-distance transport differs for individual species and is generally below 60 grains cm(-2) yr(-1). Comparisons between modern and fossil PAR from the same regions show similar values. For temperate taxa, modern analogues for fossil PARs are generally found downslope or southward of the fossil sites. While we do not find modern situations comparable to fossil PAR values of some taxa (e.g. Corylus), CO2 fertilization and land use may cause high modern PARs that are not documented in the fossil record. The modern data are now publicly available in the Neotoma Paleoecology Database and aid interpretations of fossil PAR data.
|
|
3. |
- Feurdean, Angelica, et al.
(author)
-
Origin of the forest steppe and exceptional grassland diversity in Transylvania (central-eastern Europe)
- 2015
-
In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 42:5, s. 951-963
-
Journal article (peer-reviewed)abstract
- Aim The forest steppe of the Transylvanian Plain is a landscape of exceptionally diverse steppe-like and semi-natural grasslands. Is this vegetation a remnant of a once continuous temperate forest extensively cleared by humans, or has the area, since the last glacial, always been a forest steppe? Understanding the processes that drive temperate grassland formation is important because effective management of this biome is critical to the conservation of the European cultural landscape. Location Lake Stiucii, north-western Romania, central-eastern Europe. Methods We analysed multi-proxy variables (pollen, coprophilous fungi, plant macroremains, macrocharcoal) from a 55,000year discontinuous sequence (c. 55,000-35,000; 13,000-0cal. yr bp), integrating models of pollen-based vegetation cover, biome reconstruction, global atmospheric simulations and archaeological records. Results Needleleaf woodland occurred during glacial Marine Isotope Stage (MIS) 3, but contracted at the end of this period. Forest coverage of c. 55% (early Holocene) and 65% (mid-Holocene) prevailed through the Holocene, but Bronze Age humans extensively cleared forests after 3700cal. yr bp. Forest coverage was most widespread between 8600 and 3700cal. yr bp, whereas grasses, steppe and xerothermic forbs were most extensive between 11,700 and 8600cal. yr bp and during the last 3700cal. yr bp. Cerealia pollen indicate the presence of arable agriculture by c. 7000cal. yr bp. Main conclusions We have provided the first unequivocal evidence for needleleaf woodland during glacial MIS 3 in this region. Extensive forests prevailed prior to 3700cal. yr bp, challenging the hypothesis that the Transylvanian lowlands were never wooded following the last glaciation. However, these forests were never fully closed either, reflecting dry growing season conditions, recurrent fires and anthropogenic impacts, which have favoured grassland persistence throughout the Holocene. The longevity of natural and semi-natural grasslands in the region may explain their current exceptional biodiversity. This longer-term perspective implies that future climatic warming and associated fire will maintain these grasslands.
|
|
4. |
- Filipović, Dragana, et al.
(author)
-
Triticum timopheevii s.l. ('new glume wheat') finds in regions of southern and eastern Europe across space and time
- 2024
-
In: Vegetation History and Archaeobotany. - : Springer. - 0939-6314 .- 1617-6278. ; 33:1, s. 195-208
-
Research review (peer-reviewed)abstract
- Triticum timopheevii sensu lato ('new glume wheat', NGW) was first recognised as a distinct prehistoric cereal crop through work on archaeobotanical finds from Neolithic and Bronze Age sites in northern Greece. This was later followed by its identification in archaeobotanical assemblages from other parts of Europe. This paper provides an overview of the currently known archaeobotanical finds of Timopheev's wheat in southeastern and eastern Europe and observes their temporal span and spatial distribution. To date, there are 89 prehistoric sites with these finds, located in different parts of the study region and dated from the Neolithic to the very late Iron Age. Their latest recorded presence in the region is in the last centuries bce. For assemblages from the site as a whole containing at least 30 grain and/or chaff remains of Timopheev's wheat, we take a brief look at the overall relative proportions of Triticum monococcum (einkorn), T. dicoccum (emmer) and T. timopheevii s.l. (Timopheev's wheat), the three most common glume wheats in our study region in prehistory. We highlight several sites where the overall proportions of Timopheev's wheat might be taken to suggest it was a minor component of a mixed crop (maslin), or an unmonitored inclusion in einkorn or emmer fields. At the same sites, however, there are also discrete contexts where this wheat is strongly predominant, pointing to its cultivation as a pure crop. We therefore emphasise the need to evaluate the relative representation of Timopheev's wheat at the level of individual samples or contexts before making inferences on its cultivation status. We also encourage re-examination of prehistoric and historic cereal assemblages for its remains.
|
|
5. |
- Hristova, Ivanka, et al.
(author)
-
Plant economy and vegetation of the Iron Age in Bulgaria : archaeobotanical evidence from pit deposits
- 2017
-
In: Archaeological and Anthropological Sciences. - : Springer Berlin/Heidelberg. - 1866-9557 .- 1866-9565. ; 9:7, s. 1481-1494
-
Journal article (peer-reviewed)abstract
- Major social and economical changes occurred in human societies during the Iron Age of Southeastern Europe: increasing structuring of societies, intensifying production and metal technologies and the establishment of a market economy. However, the related plant economy of the region is still poorly studied and understood. The Iron Age ‘pit field sites’ (groups of pits distributed over a certain area) in south-eastern Bulgaria were recently intensively excavated, and their study provides rich archaeobotanical assemblages, which are used for filling this gap in our knowledge. The current study presents the archaeobotanical information from 196 flotation samples from 50 Iron Age pits. The results show a wide range of annual crops, the most important of which seem to be hulled wheats (mainly einkorn), barley and also millet. A variety of pulses and fruits is retrieved, each in small quantities. Some species like Olea europaea and Cucumis melo are an indication for contacts with adjacent regions (especially the Mediterranean area). The archaeobotanical assemblages also documented the environment and land use, revealing the exploitation of a variety of habitats like cropland, open grassland, shrub land and wetland. The archaeobotanical analyses of the Iron Age pit fields show that this type of structures can be an important source of information on the Iron Age plant economy in the region.
|
|
6. |
- Hristova, Ivanka, et al.
(author)
-
Plant remains preserved in products of metal corrosion : source of evidence on ancient plant materials and environment from burial contexts
- 2024
-
In: Vegetation History and Archaeobotany. - : Springer. - 0939-6314 .- 1617-6278. ; 33:1, s. 121-130
-
Journal article (peer-reviewed)abstract
- By-products of metal corrosion, when coming into contact with organic matter, have the capacity to preserve it from decay. A pilot study was conducted aiming to explore the potential and limitations of plant remains preserved in by-products of metal corrosion for archaeobotanical research. The organic remains considered come from the surface/immediate proximity of the metal funerary artefacts of two ancient cemeteries—Varna and Messambria, Eastern Bulgaria. Metal corrosion by-products were observed and sampled, under a low magnification stereo microscope. Subsequently, the plant macrofossils recognised were analysed under reflected light and a scanning electron microscope (SEM). Additionally, pollen was extracted from the metal corrosion by-products, using standard acetolysis. The analyses from the graves of both cemeteries allowed identification of textiles and plant fibres, as well as wood (Cornus sp., Pinus sp., Viburnum sp.). At Varna cemetery epidermis fragments of Juncus sp. were recognized, while at Messambria necropolis fruits of almond were found. The pollen analysis from Varna points to use of flowers in the ritual (Daphne tetrads were recorded) and shows a notably open landscape with 77% non-arboreal pollen (NAP). The palynological analysis from the Messambria necropolis revealed the use of flowers in the burial ritual indicated by clusters of Vitis, Cistus and Rosaceae pollen. The surrounding vegetation was dominated by open oak woodland and open habitats (43% NAP) with a strong presence of anthropogenic indicators. The outcome of the study proved to be promising for reconstructing details of the burial rituals including associated plant materials, as well as the surrounding plant habitats during the functioning of the cemeteries.
|
|
7. |
- Hristova, Ivanka, et al.
(author)
-
Recognising archaeological food remains : archaeobotanical case studies from Bulgaria
- 2019
-
In: Bulgarian e-Journal of Archaeology. - : Association of Bulgarian Archaeologists (ABA). - 1314-5088. ; 9:2, s. 181-211
-
Journal article (peer-reviewed)abstract
- The paper discusses possible evidence for cereal food from seven Bulgarian archaeological sites spanning theEarly Neolithic to the Early Iron Age (6th millennium BC – 1st millennium BC). It aims to increase the awarenessof excavators towards such finds and to present the methods for collecting and extracting such remains fromarchaeological layers and their laboratory analysis. The studied remains are mainly cereal fragments, agglomerationsof fragments or amorphous/ porous masses with or without visible plant tissues. They were directlycollected from vessel contents or derived by means of flotation from bulk samples taken from floor layers closeto fireplaces/ cooking installations. The microscopic structure of the food remains is observed and described atplant tissue level under low magnification binocular, microscope with reflected light and Scanning Electron Microscope(SEM). These optical examinations were applied in order to detect alterations of the microstructure ofthe possible food remains and hence to trace the possible ways of food preparation. All the cereal food remainsfrom the Neolithic/Chalcolithic period represent coarsely ground cereals, while the later ones (Late Bronze Ageand Early Iron Age) have characteristics of finely ground cereal products and may suggest the introductionof new cooking/ baking techniques as well as shifts in food processing practices. Based on their field experienceand research results the authors strongly recommend careful sampling and documentation of any charredcrusts recognisable as such in vessel contents, and deposits around installations like ovens and fireplaces, whichcould be related to daily food preparation or ritual offerings. Such systematic study of archaeological food remainswill facilitate obtaining reliable information about food preparation and consumption in the past.
|
|
8. |
- Lazarova, Maria, et al.
(author)
-
A 5000-year pollen and plant macrofossil record from the Osogovo Mountain, Southwestern Bulgaria : Vegetation history and human impact
- 2015
-
In: Review of Palaeobotany and Palynology. - : Elsevier BV. - 0034-6667 .- 1879-0615. ; 223, s. 1-9
-
Journal article (peer-reviewed)abstract
- Pollen and plant macrofossil analyses were performed on a sequence 105 cm deep obtained from a peat bog (1750 m) that is located above the present timber-line in the Osogovo Mountain, Southwestern Bulgaria. The palaeovegetation reconstruction, supported by a radiocarbon chronology, revealed the vegetation dynamics and human impact during the last 5000 years. The peat bog formed when a coniferous belt of Abies alba and Pinus (Pinus sylvestris, Pinus nigra) covered the high mountain slopes. Charcoal fragments indicate the presence of a broad-leaved tree community composed of Quercus, Corylus, Carpinus, Tilia, Acer and Ulmus at lower altitudes. Stands of Fagus sylvatica in places with higher air and soil humidity, like river valleys and deep ravines, became established. The pollen assemblages after c. 3200 cal. BP record an important change in the forest composition that led to the replacement of the conifers, mostly A. alba, by the invading communities of F. sylvatica. The reasons for this replacement included factors related to both climate change and anthropogenic disturbance. During the last centuries a large-scale degradation of the woodlands in the mountain has occurred. On a regional scale the palaeoecological evidence is compared with information from palynological, archaeological and historical sources in Southwestern Bulgaria.
|
|
9. |
|
|
10. |
- Nikov, Krassimir, et al.
(author)
-
Food supply and disposal of food remains at Late Bronze and Early Iron Age Ada Tepe : bioarchaeological aspects of food production,processing and consumption
- 2018
-
In: Social dimensions of food in the Prehistoric Balkans. - : Oxbow Books. - 9781789250800 - 9781789250817 ; , s. 278-299
-
Book chapter (peer-reviewed)abstract
- The site Ada Tepe situated in Eastern Rhodope Mountains (South Bulgaria) represents an unique gold mining complex continuously occupied from Late Bronze Age to the Early Iron Age. The excavations of the site revealed apart of the extensive mining activities also settlement layers bearing diverse evidence on the ancient food supply of the gold mining complex. As food represents a basic human need and cultural and technological innovations related with the metallurgy often influenced the subsistence and caused shifts in diet of the ancient population. In this paper we would like to explore such changes and shifts based on the available archaeological and archaeobotanical evidence from Ada Tepe. To achieve this the ceramic inventory of the found buildings is evaluated in terms of their meaning for food preparation and consumption. This evidence is crosschecked with the archaeobotanical evidence of disposed at the archaeological structures remains of cultivated plants, processed plant products (like porridge and bread remains) and such with possible imported character (like figs).
|
|