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This paper presents the results of the explorations carried out in the western sector of the Iberian Central System (western Gredos, Béjar, Gata and Estrela mountain ranges). The macroremains found allow detailing the model of the landscape transformation, the composition and extension of their vegetal formations throughout the Holocene. Ninety-nine woody macroremains, 3 bark remains and 8 pinecones were located from eight sites between 875 and 1860 m above sea level, among which 15 radiocarbon dates were made. The taxonomic identification of two trunks found in Estrela allows us to document the local presence of Pinus cf. sylvestris ca. 6600 cal BP in this site. The same taxon also appears at the western end of Gredos between ca. 1700–2800 cal BP at approximately 1300 m. These remains expand the Holocene distribution of P. cf. sylvestris in the Central System known to date, both temporally and geographically. In parallel, the macroremains analysed document the composition of high mountain scrub (Cytisus type, Erica cf. arborea) in Béjar (ca. 1860 m), as well as mixed scrub-woodland formations in Gata (975–1180 m), which included deciduous Quercus , Betulaceae and Ericaceae. The presence of P. pinaster at ca. 6200 cal BP and 1180 m in this mountain range constitutes the earliest palaeobotanical evidence of this species recorded in Gata. The main results support the continuous persistence of plant formations in which P. sylvestris , P. nigra , and P. pinaster would have formed part throughout the Iberian Central System during the Holocene in a wide altitudinal range (1100–1840 m). • Above one hundred Holocene macrofossils from eight different sites were analysed. • Pinus sylvestris recently disappeared from the western Central System. • P. gr. sylvestris remained in Serra da Estrela until ˜6650 years ago. • First evidence of Pinus pinaster has been found in Gata ˜6200 years ago. • Betula , Quercus , Alnus and Ericaceae Holocene macroremains were found in Gata. [ABSTRACT FROM AUTHOR]

Over the last millennia, the land between the Alps and the Mediterranean Sea, characterized by extraordinary habitat diversity, has seen an outstanding cross-cultural development. For the first time, this paper reports on the census of the Holocene archaeological sites that have been studied as part of archaeobotany in Italy (continental Italy, the Italian peninsula and islands) over the last quarter in a century. Pollen, non-pollen palynomorphs, seeds and fruits, woods/charcoals and other plant remains have all been analysed in multidisciplinary researches. A list of 630 sites has been provided by more than 15 archaeobotanical teams. The sites are located across the 20 regions of Italy, and in the Republic of San Marino (356 sites in northern Italy, 118 in central Italy, 156 in southern Italy and on the islands). They belong to several cultural phases: 321 sites are only pre-Roman, 264 are Roman/post-Roman, and 45 sites cover a broader range of time, present in both time spans. Site distribution is plotted in maps of site density according to geographical districts and the main chronological phases. The reference list helps to find analytical data referring to the descriptive papers that may be scattered throughout monographs and specific books on the matter. [ABSTRACT FROM AUTHOR]

This paper describes specimens of Pediastrum argentinense -type in Late Quaternary sediments, focusing on their morphological variability and stressing their value for palaeobotanical studies. Although the taxon strongly resembles P . argentinense Bourrelly et Tell in Tell, known only from South America, some morphological differences between P . argentinense and P. argentinense -type lead to the conclusion that we are dealing with a separate taxon provisionally named P . argentinense -type. To make its taxonomic position clear, there is a need for detailed morphological observations of living specimens and molecular analyses. This taxon was found in sections spanning the entire Late Glacial and Holocene periods across Central Europe. Its affinity to sediments originating in shallow and strongly overgrown water bodies makes it a good indicator of such conditions in past environments. [ABSTRACT FROM AUTHOR]

Abstract: Numerous taphonomic and statistical factors influence the composition of the palynological record and the interpretation of pollen count data is far from simple. Quantification of the condition in which the pollen has been preserved can increase the confidence of such interpretation by highlighting parts of the record that are likely to have been influenced by changing taphonomy. Despite the benefits, preservation analysis is a relatively under-used technique and there remain a lack of observational data from a wide range of geographical locations and depositional contexts. This paper presents the results of detailed pollen preservation analyses completed for four in-filled basins from Holderness, lowland eastern England. We examine the Holocene pollen records in detail and employ what we believe to be a novel methodology — the definition and assignment of Local Pollen Preservation Zones — to help assess patterns of pollen deterioration, both within and between sites. The data obtained are used to consider a range of topics, including the evidence for local and regional influences on pollen deterioration frequency, relationships between preservation and broad-scale aspects of the depositional environment, and the origins of occasional incidences of pollen from major arboreal taxa. Evidence for two different forms of perforation corrosion is also discussed. The outcomes of this study are of relevance to palynological investigations over a range of timescales, not just the Holocene, and we hope that this contribution will stimulate further consideration of the role that pollen preservation analysis can contribute to palynology as a discipline. [Copyright &y& Elsevier]

Abstract: Possible effects of seismic activity in the Dead Sea basin on the regional vegetation distribution are presented in this paper. The palynology was investigated in high resolution at the Holocene outcrop near the Ein Feshkha oasis. Pollen samples were collected from three intervals (A, B, D), with thicknesses of 5–15 cm, containing 1–2 seismites each, and from one undisturbed layer (interval C). All four intervals are from the same Ein Feshkha outcrop section, but from different depths. In two of the intervals (B, C) the main pollen indicators (e.g. Olea, Pinus, Asteroideae, Cichorioideae) show no significant aberrations from the typical pollen fluctuations. Interval A, deposited during the late Byzantine period, shows a decline of Olea percentages immediately after the sedimentation of a breccia layer (interpreted as a seismite). While this decrease in olive percentages predominantly reflects an aridification crisis at the end of the Byzantine period, damage to olive orchards due to earthquake (root damages, collapses of the crowns) and/or the abandonment of cultivated land as a consequence of an earthquake cannot be ruled out. Nevertheless, minor anthropogenic indicators like Vitis or Juglans, which show low abundances in the pollen diagram of Ein Feshkha, as well as other trees and herbs, are not affected by the late Byzantine earthquake. Interval D, deposited during the Hellenistic–Roman period, shows a slight decrease of Olea and an increase of Cichorioideae after the deposition of a seismite. Our hypothesis that earthquakes might have affected vegetation dynamics in intervals A and D is supported by cluster analysis. While the data of this study do not support the use of pollen as a reliable paleoseismic tool in the lacustrine environment of the Dead Sea, some small effects of earthquakes on pollen fluctuations cannot be excluded. [Copyright &y& Elsevier]

Abstract: In this paper we present a review of the available pollen analyses in the north-western Iberian Range with the aim of studying Fagus glacial refugia and Holocene expansion. The work collects the available pollen analyses in the area (24 sites and 58 14C dates). Based on the available palynological data, we try to reconstruct the changes that occurred in the distribution of Fagus sylvatica in the north-western Iberian Range during the late Pleistocene and the Holocene, its spread patterns and the possible causes for such changes. Results from pollen analyses allow establishing at the Middle Holocene the beginnings of Fagus expansion mostly in relation to anthropic activities. Also, the pollen data demonstrate the existence of Fagus glacial refuge during the Late Pleistocene and the Early Holocene. Therefore, we hypothesize that present-day beech forests, in the area under study, are the direct result of the relic populations that survived the last glaciations and that have been favoured by both environmental conditions and human activities. [Copyright &y& Elsevier]

Abstract: Alder (Alnus) wood peats have only rarely been subject of palaeoecological research because their bad preservation generally prevents successful reconstruction of local and regional vegetation development by means of macrofossil and pollen analysis. To test the potential of non-pollen palynomorphs as an additional source of information, an Alder peat core from the Ziese river valley (NE-Germany) was analysed for macro- and microfossils with special focus on non-pollen palynomorphs (NPPs). 129 new types of NPPs, mostly fungal spores and remains of decomposed wood, were identified. In this paper we describe 12 new types; 13 other new types are described by Prager et al. [Prager, A., Barthelmes, A., Theuerkauf, M., Joosten, H., 2006. Non-pollen palynomorphs from modern Alder carrs and their potential for interpreting microfossil data from peat. Rev. Palaeobot. Palynol. 141, doi:10.1016/j.revpalbo.2006.03.015]. In addition 25 types already described in literature were used for interpretation of fossil samples. The pollen and macrofossil content revealed that the upper section of the core has been formed in a very wet Alder carr and Willow–Alder-shrub. For the lower, strongly decomposed section, NPPs were necessary to reconstruct an Alder carr as the peat forming vegetation. Our research reaffirms that substantial additional ecological information can be derived from analysing NPPs, especially in highly decomposed Alder peats. [Copyright &y& Elsevier]

Abstract: The aim of this paper is to document the Holocene (6000 years BP to the present) vegetation trends on the summit of three tepuis (table mountains), from one of the largest and highest tepuian massifs of the Neotropical Guayana region, the Chimantá, situated in Venezuela. The tepui summits are almost pristine and unique sites to record natural forcings and ecosystem responses. Here, pollen analysis and radiocarbon dating of four peat sequences obtained with a manual Hiller borer are presented, and compared with modern analogues from surface samples, for interpretation. Highland tepuian meadows have been the dominant vegetation type throughout the time interval studied. The sequences studied exhibited different minor vegetation patterns in time, recording primarily local vegetation dynamics, such as lateral variations in the forest–meadow ecotones, and quantitative shifts in the dominant meadow taxa. Moderate climatic shifts formerly reported for other localities were not recorded here, probably because the intermediate altitude and the geomorphological characteristics of the sites studied made them insensitive to subtle regional changes in temperature and moisture, which are hidden by local vegetation shifts. The results of the present study allowed estimation of the magnitude of formerly reported vegetation shifts in the same massif. In the studied sites, the constancy in the vegetation through time cannot be considered only as the result of a high degree of climatic stability, but also the consequence of site insensitivity. [Copyright &y& Elsevier]

Abstract: Zelkova pollen has been found in Oligocene- to Pleistocene-aged deposits from many parts of Europe and northern Africa, but became extinct in mainland Europe prior to the last glacial maximum. This paper presents some observations on the ecology, pollen productivity and Holocene history of Zelkova carpinifolia to further understanding of Quaternary climatic trends. Georgia is one of the last refuges of this Tertiary relict tree. Based on palynological data from 20 Holocene sediment profiles in Georgia, we have established that Zelkova pollen is almost always accompanied by elevated proportions of thermophilous taxa (Castanea sativa, Quercus hartwissiana, Quercus iberica, and Pterocarya pterocarpa) in pollen spectra. These spectra are associated with phases of climatic amelioration and humidification. Zelkova carpinifolia is characterised by low pollen productivity and is underrepresented in pollen spectra by four-to-five orders of magnitude. Because of this, even single grains of Zelkova pollen may play a significant role in pollen-based climatic reconstructions. Six major climatic optima occurred in Georgia through the course of the Holocene, the longest and warmest of which occurred in the mid-Holocene and reached its maximum between 6000 and 5500 Cal. yr BP. During that period, Zelkova and Castanea forests were widespread. In Western Georgia, the upper tree line was elevated by as much as 300 m above its present-day level. In semiarid Eastern Georgia, the tree line may have been 500–600 m higher. Other climatic optima are seen in late-Holocene pollen spectra dating to 3800–2500 Cal. yr BP and 1350–800 Cal. yr BP. [Copyright &y& Elsevier]

Abstract: This paper presents a mid- to late-Holocene vegetation sequence of a Juniperus thurifera-dominated area in the eastern, continental plateaux of the Segura Mountains of southeastern Spain. A mid-Holocene maximum of mesic tress is recorded in the pollen diagram between c. 6640 and 4790 cal years BP with the vegetation dominated by deciduous oaks. A dramatic decline in deciduous oaks occurred from approximately 4700 cal years BP to be replaced initially by evergreen oak, and then junipers and other xerophytes from c. 4500 cal years BP. This trend of xericness in the vegetation is coherent with regional and extra-regional palaeoclimatic records for increased mid-Holocene aridity. Significant anthropogenic modification of the vegetation occurred in this region from c. 1350 cal years BP represented by a large reduction in all tree taxa (except Juniperus) and increases of thorny scrub and nitrophilous assemblages. Increased fire incidence, pastoralism, and arboriculture were associated with this anthropogenic activity. We conclude that present-day J. thurifera-dominated communities in this region have become established through a combination of two predominant processes; increased aridification from c.4500 cal years BP and anthropogenic activity from c. 1200 cal years BP. [Copyright &y& Elsevier]