Małgorzata Latałowa

Seasonal variations in the atmospheric Betula pollen count in Gdańsk (southern Baltic coast) in relation to meteorological parameters

Seven years of observations of thepatterns and fluctuations in atmosphericBetula pollen concentration with respect tometeorological variables enable the mostimportant factors shaping the pollen season ofbirches in the Gdańsk area (northernPoland) to be defined. The correlation factorsfor different aspects of the pollen season andparticular meteorological variables arepresented. A biennial cyclic rhythm is observedin the annual pollen sums. The starting date ofthe Betula pollen season is a ratherstable parameter for those years whichrepresent the average, most typical,meteorological conditions as recorded for thearea.

Pollen-based quantitative reconstructions of Holocene regional vegetation cover (plant-functional types and land-cover types) in Europe suitable for climate modelling

We present quantitative reconstructions of regional vegetation cover in north-western Europe, western Europe north of the Alps, and eastern Europe for five time windows in the Holocene [around 6k, 3k, 0.5k, 0.2k, and 0.05k calendar years before present (bp)] at a 1° × 1° spatial scale with the objective of producing vegetation descriptions suitable for climate modelling. The REVEALS model was applied on 636 pollen records from lakes and bogs to reconstruct the past cover of 25 plant taxa grouped into 10 plant-functional types and three land-cover types [evergreen trees, summer-green (deciduous) trees, and open land]. The model corrects for some of the biases in pollen percentages by using pollen productivity estimates and fall speeds of pollen, and by applying simple but robust models of pollen dispersal and deposition. The emerging patterns of tree migration and deforestation between 6k bp and modern time in the REVEALS estimates agree with our general understanding of the vegetation history of Europe based on pollen percentages. However, the degree of anthropogenic deforestation (i.e. cover of cultivated and grazing land) at 3k, 0.5k, and 0.2k bp is significantly higher than deduced from pollen percentages. This is also the case at 6k in some parts of Europe, in particular Britain and Ireland. Furthermore, the relationship between summer-green and evergreen trees, and between individual tree taxa, differs significantly when expressed as pollen percentages or as REVEALS estimates of tree cover. For instance, when Pinus is dominant over Picea as pollen percentages, Picea is dominant over Pinus as REVEALS estimates. These differences play a major role in the reconstruction of European landscapes and for the study of land cover-climate interactions, biodiversity and human resources.

Tilia forest dynamics, Kretzschmaria deusta attack, and mire hydrology as palaeoecological proxies for mid-Holocene climate reconstruction in the Kashubian Lake District (N Poland)

Pollen, non-pollen palynomorph, macrofossil, and lithological analyses of mid-Holocene deposits from a small peat bog in northern Poland provide new proxy data on vegetation dynamics and climate between c. 9500 and 4600 cal. BP. The most prominent wetter climate phases occurred between c. 9500 and 9280±160 and between c. 5000 and 4600 cal. BP while a hot and dry period between 8185±145 and 5299±195 cal. BP corresponds with the Holocene Thermal Maximum (HTM). The HTM phase has been characterized by absolute dominance of Tilia cordata and the presence of T. platyphyllos beyond its current geographical range limit and a c. 2700 yr long, high incidence of the parasite fungus Kretzschmaria deusta in the local forest stand, concurrent with a dry phase on the mire. For the HTM, we suggest mean summer temperatures at least 3°C higher than today’s values. These data are in accordance with the geographic pattern of the HTM temperature anomalies in northern Europe, including the Baltic region, which suggest a gradient of positive anomalies from north to south and from west to east. The data also illustrate the effect of climate warming on the mid-Holocene pathogen outbreak and may indicate intensive vegetative reproduction as a Tilia strategy for population survival. Summer drought was probably important for high success of K. deusta in infecting weakened Tilia trees.

Pollen productivity estimates from old-growth forest strongly differ from those obtained in cultural landscapes: Evidence from the Białowieża National Park, Poland

Pollen productivity estimates of individual plant taxa are necessary when determining changes of vegetation cover during the Holocene. To date, studies describing this parameter in lowland temperate Europe have been carried out in cultural landscapes showing low forest cover and dominated by human activities. However, these may be of limited use when applied to reconstruct past land cover, for instance, from pre-agricultural landscapes. The aim of this paper is to ascertain whether pollen productivity from the closed-canopy old-growth forest in the Białowieża National Park, Poland, where human impact has been minimal for nearly a century, is different from that calculated in much more open landscapes. We ask: how much does forest antiquity and structure influence the amount of pollen released from particular taxa? We implemented maximum likelihood estimation of relative pollen productivity for seven tree species and for Poaceae using 18 modern pollen assemblages and distance-weighted plant abundances. Our results demonstrate that the ratio of pollen productivity between high producers (Pinus sylvestris and Quercus robur) and low producers (Poaceae, Corylus avellana) is on an average six times greater in Białowieża than across other European cultural landscapes. Pollen from forest Poaceae and C. avellana is six times more under-represented in old-growth forest than hitherto estimated from cultural landscapes. This finding reinforces the idea that pollen productivity can vary in response to changes in the prevailing environmental settings and we present for the first time a quantification of this variability, likely induced by differences in light availability.

The comparison of archaeobotanical data and the oldest documentary records (14th–15th century) of useful plants in medieval Gdańsk, northern Poland

This paper presents a comparison of archaeobotanical data with information about useful plants from the oldest (14th–15th century) written sources that have survived in the archives of Gdańsk, northern Poland. The main information on plant products, available in medieval documents from Gdańsk, concerns taxa traded by merchants as well as those used by the Teutonic Knights or the city council of Gdańsk. In these sources, as well as from many records about cereals, numerous spices and vegetables are listed which do not have counterparts in the archaeobotanical remains which have been found. On the other hand, the archaeobotanical data complement our knowledge on the use of common plants, both cultivated and collected in the wild, which written sources do not mention. This situation is most apparent in the case of local fruits like plums, cherries or berries, of which numerous remains are proof of their considerable popularity in Gdańsk. This would be impossible to conclude on the basis of historical documents only, whose attention is focused on the more expensive and imported plant products.

The archaeobotanical record of Staphylea pinnata L. from the 3rd/4th century A.D. in northern Poland

Artefacts made of Staphylea pinnata seeds have been found in a grave dated to the late Roman period discovered in Pruszcz Gdański (northern Poland). This record is discussed against the background of the present-day distribution range of this species and its Holocene fossil localities. The role of man in the extension of the primary area of occurrence of the species has been emphasised.

The last 1500 years on Wolin Island (NW Poland) in the light of palaeobotanical studies

Abstract On the basis of pollen analysis of profiles from three localities on Wolin Island (southern Baltic), the natural diversity of the vegetation and the anthropogenic changes since the 5th century AD is presented. Attention is drawn to the important part played by the town and port, situated here in the early Middle Ages, in the changes to the natural environment of the whole island. It was found that because of the poor soils on the island, corn probably had to be imported. Preliminary results of the plant macrofossil analysis of the archaeological profile from the early medieval ports quayside, indicate that corn from southern areas was shipped to Wolin; evidence for this is the presence in the fossil material of a group of species from the Caucalidion alliance.

Postglacial Evolution of the Odra River Mouth, Poland-Germany

As revealed by multidisciplinary research, the Odra River mouth area was evolving during the Late Glacial and Holocene by changing from glacio-fluvial to fluvio-limnic to marine through to the present lagoonal area. In the Late Pleistocene, the pre-Odra River was rolling westward along the Torun-Eberswalde ice-marginal valley to discharge, farther away and like the rivers Elbe and Rhine, to the Atlantic. After the Scandinavian icesheet retreat (ca. 14.5 ky BP), the ancient river was flowing north-west to discharge to the Baltic Sea, most likely close to the eastern part of today’s Island of Rugen. Initially, the Odra was a braided river of a type, with many wandering channels and sandbanks. In the early Holocene, the river became anastomosing, with stabilised channels. In the mid-Holocene, the Odra was most likely meandering through swamps and bogs. In the late Atlantic period, during the Littorina transgression (ca. 7 ky BP), the river valley was invaded by the sea water and was transformed into a marine embayment extending southward down to today’s city of Szczecin. The river mouth area became an estuary. During the marine transgression, erosion processes affected two islands composed of glacial sediments: the Wolin and the Usedom. Erosion of the islands and the intensifying longshore transport produced two sandy spits which grew in size and gradually blocked the embayment, turning it into a lagoon. At present, the Odra River mouth area shows characteristics of a lagoon.

From wetland to commercial centre: the natural history of Wyspa Spichrzów (“Granary Island”) in medieval Gdańsk, northern Poland

This paper describes the analyses of pollen, non-pollen palynomorphs, macroremains and geochemistry in sediments from archaeological excavations at Wyspa Spichrzów (“Granary Island”) in Gdańsk, northern Poland. The aim of this study was to reconstruct the environmental conditions in this part of the town in the period preceding its occupation and during its transformation with the establishment of a trade centre and an increasing number of granaries, warehouses and workshops. The results show that this area was originally covered by wetlands typical of river oxbows, with a landscape formed by alder woods, shallow pools of water, fens and patches of wet meadows. Around the 9th–10th centuries, a distinct lowering of the groundwater table reduced the pools, and the alder stands also reduced. These changes coincided with the Medieval Climatic Anomaly. Drying of the ground could have been an important factor enabling expansion of settlement in the Gdańsk area. Between the 10th and 13th–14th centuries, the area around the investigated sites was probably used as pasture, as shown by high frequencies of coprophilous fungal spores. A large representation of cereal pollen and pollen and macroremains of field weeds reflects crop transport and storage on the island from ca. the 13th/14th centuries in the northern part of the area and the 15th/16th centuries in its southern part. The increasing human impact caused development of a rich flora associated with human activities, habitat enrichment by nitrogen and phosphorus, and heavy metal pollution from the beginning of the 13th century.

The potential of palaeoecological studies in archaeological wetland sites of the southern Baltic regions

The ancient lake settlement tradition is not characteristic of one particular geographical area or time period, but it is spread over various European regions and dates from the Neolithic to the Middle Ages (Menotti and O’Sullivan 2013). Already in the 19th century, lake settlements were discovered in the Baltic region as well as elsewhere. Although research concentrated on sites in Poland up to the end of the 20th century (Pydyn and Gackowski 2011; Pranck _ enait _ e 2014, this volume), recent discoveries have directed attention to Lake Luokesa (Luokesai ežeras), Lithuania, as the five articles in the present issue show. The Luokesa lake settlements L1 and L2, dated to the transition from the Late Bronze Age to the Early Iron Age, were discovered at the very beginning of the 21st century and excavated between 2000 and 2011. The excavation (mainly of L1) was carried out underwater and revealed a thick cultural layer, containing extraordinarily well preserved organic material, which allowed an unprecedented interdisciplinary palaeoecological investigation. In contrast, site L2 which was located on the opposite side of the lake consisted of a barren wooden platform without any cultural layers. Excavations were carried out by a team from the Department of Archaeology at Vilnius University and the Lithuanian Cultural Heritage Centre which included Z. Baubonis, R. Kraniauskas, M. Kvedaravicius, G. Motuzait _ e-Matuzeviciūt _ e, E. Pranck _ enait _ e and numerous volunteers. Part of the excavations and, above all, the entire palaeoecological investigations, which comprised soil micromorphology, pollen and plant macroremain analyses and dendrochronological studies carried out between 2008 and 2011, were fully funded by the Swiss National Foundation for Scientific Research within the Project ‘‘Understanding human occupation in later prehistoric Europe’’ (No. NF K-13K1-117893), directed by Francesco Menotti (IPAS, Basel University). The first article by E. Pranck _ enait _ e gives a comprehensive overview of the history of lake settlement research in north-eastern Europe. The excavated settlement structures and finds at L1 and L2 are presented and the importance and unusual nature of the settlements stressed. Formerly raised hypotheses and interpretations of the origins as well as the development and use of the region’s lake settlements are discussed. This article forms an important review and starting point for the other papers dealing with the Luokesa sites, which present results of dendrochronology, geoarchaeology, palynology and archaeobotany. The dendrochronological study by N. Bleicher allows the Luokesa lake settlements to be placed within a precise Late Bronze/Early Iron Age (LBA/EIA) chronology for the first time. A 90 year long floating chronology of the settlement could be established and fitted to the time axis by wiggle-matching radiocarbon dates to 625 and 535 BC (2r range). The duration of the settlements however was much shorter, for example L1 was in use for only ca. 16 years. S. Jacomet (&) Department of Environmental Sciences, Basel University, Institute for Prehistory and Archaeological Science, Spalenring 145, 4055 Basel, Switzerland e-mail: stefanie.jacomet@unibas.ch