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The vegetation history of the Central Rila Mountains for the last 14,000 years was reconstructed by means of pollen analysis and radiocarbon chronology of a core retrieved from Lake Manastirsko-2 (2326 m). The Lateglacial landscape was dominated by open herb vegetation composed of Artemisia, Chenopodiaceae, Poaceae, and other cold-resistant herbs (14,000–11,700 cal. yr BP). Stands of Pinus, Betula, and Juniperus–Ephedra shrubland partly enlarged during the Lateglacial interstadial. Pioneer forests of Betula with Pinus and Juniperus occupied barren soils in the early Holocene (11,700–7900 cal. yr BP), while mixed oak forests with Tilia, Ulmus, Acer, and later on Corylus spread at lower elevations. A coniferous forest belt with Pinus sylvestris, Pinus peuce, and Abies developed after 7900 cal. yr BP in the conditions of milder winters, cooler summers, and increase in precipitation. The late Holocene dynamic vegetation changes were associated with the invasion of Picea abies after 3400 cal. yr BP, while Fagus communities slightly enlarged in the river valleys. Indications of human activities are visible in the pollen diagram since the ‘Late Bronze Age’ (3400–3200 cal. yr BP). The vegetation development in the study area followed a similar pattern when compared with palynological and macrofossil records from other parts of the Rila and the adjacent Northern Pirin Mountains. On a larger geographical scale, the postglacial vegetation history of the Rila Mountains displays common features with sites in the Romanian Carpathians, whereas the differences observed are result of the location of tree refugia, competing abilities, climate changes, and human activities. [ABSTRACT FROM AUTHOR]

This paper compares pollen spectra derived from modified Tauber traps and moss samples from a selection of woodland types from Bulgaria, the Czech Republic, Georgia, Greece, Poland, Switzerland and Wales. The study examines the representation of individual taxa in the two sampling media and aims to ascertain the duration of pollen deposition captured by a moss. The latter aim was pursued through the calculation of dissimilarity indexes to assess how many years of pollen deposited in a pollen trap yield percentage values that are most similar to those obtained from the moss. The results are broadly scattered; the majority of moss samples being most similar to several years of pollen deposition in the adjacent trap. For a selection of samples, a comparison of the pollen accumulation rate in pollen traps with the pollen concentration in the moss per unit surface indicates that the entrapment and/or preservation of individual pollen types in the moss differ from that in the pollen trap. A comparison of the proportion of different taxa in the moss with the pollen spectrum of 2 years of pollen deposition in the trap also revealed large differences. There is a tendency for bisaccate grains such as Pinus and Picea to have a higher representation in moss than in traps but there is considerable regional variation. The results indicate that pollen proportions from moss samples often represent the pollen deposition of one area over several years. However, bisaccate pollen grains tend to be over-represented in moss samples compared to both pollen traps and, potentially, lake sediments. [ABSTRACT FROM AUTHOR]

Abstract: Pollen analysis of sediments from the glacial Lake Trilistnika (2216m) in the Northwestern Rila Mountains (Bulgaria), supplemented by 13 radiocarbon dates, allowed the reconstruction of the palaeoenvironment and vegetation history in postglacial time. The exact time of the cirque glacier retreat is still under discussion but the lake was free of ice before 15,000cal.BP, when sedimentation of gray silt began. The lateglacial vegetation, composed of Artemisia, Chenopodiaceae and Poaceae, with isolated stands of Pinus and Juniperus–Ephedra shrubland, dominated during the stadials and partly retreated during the Bølling/Allerød interstadial complex. The afforestation in the early Holocene (11,500–7800cal.BP) started with the distribution of pioneer Betula forests with groups of Pinus (P. mugo, P. sylvestris and P. peuce) at mid-high altitudes, and Quercus forests with Tilia, Ulmus, Fraxinus, Corylus below the birch zone. The change to more humid and cooler climate ca. 7800–7500cal.BP favored the vertical migration of Abies, P. sylvestris and P. peuce. The establishment of Fagus sylvatica took place after 5200cal.BP, when pure or mixed beech communities were formed. The last tree which invaded the coniferous belt between 4300 and 3400cal.BP was Picea abies. The first expansion maximum of spruce was recorded after ca. 2700cal.BP. The vegetation development in historical times was also influenced by human interference, indicated by the continuous presence of pollen anthropogenic indicators such as Triticum, Secale, Hordeum, Plantago lanceolata, Rumex, Scleranthus, Juniperus. [Copyright &y& Elsevier]

Pollen analysis was performed on a 343 cm long core recovered from Lake Ribno Banderishko (2190 m) on Northern Pirin Mountain (southwestern Bulgaria), supplemented by six [sup 14]C AMS dates. The lower part of the sequence (343-290 cm) was deposited during the Lateglacial when mountain-steppe vegetation with Artemisia, Poaceae, Chenopodiaceae and other herbs, and with stands of Pinus and Juniperus, dominated at high altitudes. The identification of pollen of mesophilous trees suggests that local populations may have survived in refuges below 1000 m where environmental conditions were favourable for their growth. The reforestation dynamics in early-Holocene times (11200-8400 cal. BP) started with Betula forests at high altitudes and deciduous forests with Quercus, Ulmus, Tilia and Fraxinus excelsior at lower altitudes. The time of the maximal spread of Corylus at c. 8000 cal. BP coincided with the establishment of Abies alba in the forests, and the beginning of the formation of a coniferous belt, dominated by pines (Pinus sylvestris, P. peuce, P. nigra and P. heldreichii). The late immigrants Fagus sylvatica and Picea abies invaded the mountain slopes at c. 4400 cal. BP and 3300 cal. BP, respectively. Palynological traces of anthropogenic activity and landscape management began after c. 2200 cal. BP. [ABSTRACT FROM AUTHOR]

The article offers information on the Lateglacial vegetation at the Lake Sedmo Rilsko in Bulgaria. It mentions that in September 1994, the lateglacial core RD7B was collected from the center of the lake and at the depth of 8.25 meters, but lack with radiocarbon control. It adds that it sampled 100% of the pollen grains at the core except for aquatic plants, spores of pteridophytes, and Cyperaceae.

A palynological study was performed on a 2 m thick sediment sequence recovered from Mire Kupena (1356 m), a former lake in the Western Rhodopes Mountains (south Bulgaria) and supported by radiocarbon dating. The record extends back to ca. 30,000 cal. yrs. BP (Middle Pleniglacial) when the study area was occupied by wooded steppe composed of Pinus sp., Pinus peuce, some Betula, Juniperus, and cold-tolerant herb vegetation dominated by Artemisia and Chenopodiaceae. In addition, the almost continuous presence of deciduous Quercus, Tilia, Corylus, Abies, Picea, Fagus, Alnus, and Carpinus betulus pollen suggests interstadial conditions and this area could be recognized as a montane refugial place. A reconstruction of the interval between ca. 24,000 and 15,000 cal. yrs. BP was not possible due to an extremely low sediment accumulation rates or, more likely, a hiatus. The lateglacial landscape was dominated by mountain-herb steppe vegetation with isolated stands of Pinus, Betula and shrubland of Juniperus. The afforestation in the Early Holocene started with broad-leaved forests composed of Quercus with C. betulus, Carpinus orientalis/Ostrya, Ulmus, Tilia and Corylus and minor amounts of Pinus, Betula and Abies. In the Late Holocene (< ca. 4700 cal. yrs. BP) Fagus began to gain importance chiefly at the expense of the mixed oak forests, while after ca. 2000 cal. yrs. BP forests of Pinus sylvestris with some P. peuce quickly expanded around the mire. A comparison with other long palynological records from the mountains and lowlands of Bulgaria and in northern Greece reveals not only common trends in the vegetation development that are a reflection of the climate changes, but also site-specific features related to the location and topography of each site. [ABSTRACT FROM AUTHOR]