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Palaeoecological reconstructions from the region of southwestern Bulgaria were used for inferring the human impact on the vegetation and landscape during the last 8 millennia. They are based on data from pollen analyses of lakes and peat-bogs, plant macrofossils, archaeobotanical finds and radiocarbon dating. During the early Holocene, after 7900 cal. b.p. (5950 cal. b.c.) the climate changed to cooler summers, milder winters and higher precipitation resulting in the formation of a coniferous belt dominated by Pinus sp. and Abies alba. These favorable environmental pre-conditions had a positive influence on the Neolithisation of the Balkans after the 8200 cal. b.p. (6250 cal. b.c.) cold event, which caused drought in the Eastern Mediterranean. Direct evidence from wood charcoal records from the Neolithic settlement layers in the study area shows a slight modification of the surrounding woodlands and an increase of the light-demanding components, probably expressed through larger forest border zones and thinning out of the wood stands. The increase in the number of settlements in the valleys of southwestern Bulgaria intensified the human activity visible in the palaeobotanical record from 6950 cal. b.p. (5000 cal. b.c.) onwards. Between ca. 5700–5100 cal. b.p. (3800–3200 cal. b.c.) signs of anthropogenic influence on the vegetation are virtually absent. The intensity of human impact increased notably after 3200 cal. b.p. (1400–1250 cal. b.c., approx. Late Bronze Age), documented by a rise of pollen anthropogenic indicators. The final transformations in the natural forest cover after 2750 cal. b.p. (800 cal. b.c. onset of the Iron Age) marked the reduction of the coniferous forests dominated by Abies alba and Pinus sp. and the expansion of Fagus sylvatica and Picea abies. These vegetation changes are contemporaneous with increase of the palaeofire activities and the next peak of anthropogenic indicators. The changes in the landscape during the Roman period and the medieval period reflect regional environmental features and were forced by the diversification of anthropogenic activity.

A 7.5 m sediment core from Lake Bolata, a small former coastal liman lake in northeastern Bulgaria, was analyzed for pollen and plant macrofossil content in attempt to trace the changes in the vegetation, human impact and the influence of the Black Sea during the last ca. 6,000 years. Lake Bolata started its existence when the rising Black Sea level reached the elevation of the bottom of the depression. By that time nearly all tree species were already present in this area with the exception of Carpinus orientalis. The comparison of the arrival time of oriental hornbeam at different sites along the Bulgarian Black Sea confirmed the reliability of the local radiocarbon chronology. For the period under study the vegetation of the region around the site can be described as a forest-steppe due to NAP values higher than 40% of the pollen sum. Forests on the slopes of the river canyon consisted of Quercus spp., Acer, Carpinus orientalis, Fraxinus ornus, Fagus and possibly Tilia. Riverine forests formed stands composed of Salix, Alnus, Ulmus, Fraxinus, Carpinus betulus and Vitis as a liana. The vegetation on the Cape Kaliakra plateau, bordering the canyon, was dominated by diverse herbs and most of these could be considered xerophytes. The oldest occupation period belongs to the Eneolithic, documented by the occurrences of Triticum-type pollen at 5570–5170 cal b.p. (3620–3220 b.c.). The next period of higher continuous Cerealia-type values corresponds to 3450–1830 cal b.p. (1500 b.c.–a.d. 120). The macrofossil record chiefly provides evidence about plant communities of aquatics and helophytes.

Pollen analysis, supplemented by 5 14C dates, was carried out on the lateglacial section (160 cm) of a core retrieved from the glacial Lake Trilistnika (2216 m) in the northwestern Rila Mountains (Bulgaria). The reconstruction of the lateglacial vegetation history is linked for the first time to a chronological framework for the time window 13000–10000 b.p. The delimitation of an interstadial/stadial cycle, analogous with the Bolling/Allerod-Younger Dryas from Western Europe, is based on important changes in the pollen stratigraphy. Mountain-steppe vegetation composed of Artemisia, Chenopodiaceae, Poaceae and other cold-resistant herbs, with isolated stands of Pinus and Juniperus-Ephedra shrubland, dominated the landscape after the ice-retreat. Interstadial conditions were established before 12815±130 b.p. The spread of tree vegetation at lower elevation as a response to the climate improvement was confined to the time interval 12110±95–11140±75 b.p. The Younger Dryas stadial is characterised by a re-advance of the mountain-steppe vegetation. The results are compared with other sites of lateglacial age from the high mountains (Rila, northern Pirin, western Rhodopes) in southern Bulgaria.

The results of pollen analysis of two sediment cores from lake Srebarna (northeast Bulgaria) are presented. On the basis of the palynological data and the radiocarbon dates a reconstruction of the past flora and vegetation is made. For the first time a continuous palaeosuccession is established for the area of the Danubian Dobrudza and the Ludogorie district of northeast Bulgaria: a dominance of mixed xero- and mesophilous oak woods with Carpinus betulus, Ulmus, Tilia, Corylus during the Atlantic period; mixed oak woods with increasing importance of Tilia, Ulmus, Acer and a considerable presence of Carpinus betulus and Fagus during the Sub-boreal period; degradation of the woodland vegetation and transition to secondary plant communities with Carpinus orientalis and herbs during the Sub-atlantic period.

Palynological investigation and radiocarbon dating of a 6-m core from lake Durankulak, north-eastern Bulgaria, enables vegetation development and human occupation from ca. 5500–5300 cal. B.C. onwards to be traced. Steppe vegetation that included with groves of deciduous trees asQuercus, Ulmus, Carpinus belulus andCorylus changed to a forest-steppe after 4000 cal. B.C. The archaeopalynological record indicates three distinct phases of human activity as follows: (1) 5300–4200 cal. B.C. (late Neolithic and Eneolithic) during which farming, that included a substantial arable component, was pursued, (2) 3500–3000 cal. B.C. (transition to early Bronze Age) when stock rearing appears to have dominated, and (3) after 1300 cal. B.C. (late Bronze Age) when arable farming again assumed importance. The palynological data correlate well with the rich archaeological record for human settlement that is available for the region from late Neolithic times onwards.

Unfortunately, the list of authors contains a number of duplications, omissions and other errors in the original publication of the article. The correct list appears in this erratum.

On the basis of pollen analytical investigations of two cores from Lake Varna and Lake Beloslav, the vegetation history of the Lake Varna region is traced back to the beginning of the 6th millennium B.C. A two-fold zoning system is used whereby the pollen diagrams are divided into pollen zones, based on tree migration patterns, and settlement periods. Pollen zone 1 is characterised by the absence of Carpinus betulus and Fagus sylvatica. The spread of hornbeam started at ca. 6500 B.C. (pollen zone 2) and beech at ca. 6200 B.C. (pollen zone 3), the latter being the last tree to spread into the region and considerably enrich the forests of the study area. Of the many pollen taxa representing plants that are favoured by open habitats and hence potentially indicative of human impact, only a few taxa are regarded as reliable indicators of human activity. These include above all Triticum-type, and also Secale and to a certain extent Plantago lanceolata, Rumex and Polygonum aviculare. The spatial pattern of settlements is somewhat different in the areas represented by the two profiles. At both sites the first period of settlement occurred during the 6th millennium B.C. (early Neolithic). After the Neolithic period, the main settlement periods of the Eneolithic and the Early and Middle Bronze Age are recorded. On the other hand, land-use history during the Greek and Roman periods is poorly recorded. Studies on the stratigraphy, diatoms and molluscs indicate that the sixth Black Sea transgression (6500–5800 B.C.), which reached −10 m, had considerable influence on the limnological environment.

Palynological studies and investigations on macrofossil remains have been carried out on two profiles of the Holocene sediments of Lake Arkutino situated near to the Black Sea coast of SE Bulgaria. Lake Arkutino is a freshwater lake with shallow water. The lake is separated from the Black Sea by a dune barrier. Sedimentation started at about 6100 B.P. No marine or brackish influence could be traced in the sediments although the lake level is around sea level. The history of vegetation does not display major fluctuations except for the lake vegetation itself and for the swamp forests (Longos forests) surrounding the lake. Forests on normal mineral soils were mainly occupied by deciduous oaks throughout the last 6100 years. Deciduous oaks are represented in the pollen diagrams by the Quercus robur type and the Quercus cerris type. Until about 5800 B.P., one of the two pollen diagrams indicates that forests still contained more Pinus and Corylus than afterwards. After 5800 B.P., Fagus and a hundred years later together with Carpinus betulus became more important in addition with submediterranean elements as Carpinus orientalis, Fraxinus ornus and Phillyrea. After 5200 B.P., Carpinus betulus became somewhat less important. Indicators for human influence are rare. The archaeological record speaks for a small population in the area under study since the 12th century B.C. Swamp forests of the so-called Longos forests type started to develop at about 3000 B.P. The macrofossil record offers possibilities to trace hydrological changes by tracing the history of hydrophyte and reed plant comminties. From about 5100 to at least 4000 B.P., the record for Lemnetea and Potametea communities is poor and the processes of terrestrialization was interrupted. It can be assumed that the highest Black Sea transgression which is dated to 5700–4000 B.P. and which showed a sea level 3–4 m higher than today heavily influenced Lake Arkutino. That may have resulted in a higher lake level and in some water supply from the nearby river Ropotamo which would explain certain changes in the sediments and in the composition of hydrophyte communities.