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Integration of a diverse set of data from pollen, wood, macrofossils and dendrochronological studies from the Sierra de Ayllón, a mountainous region in central Spain, enables one of the most complete palaeoecological vegetation reconstructions for almost the whole Holocene on the Iberian Peninsula. Previously, the absence of pollen data for the early Holocene in the eastern part of the Sistema Central mountains had been a gap in the information needed for correctly reconstructing palaeoenvironmental change there. Our pollen study on the Valdojos site finally allows this issue to be resolved. This analysis highlights the crucial role played by pine woodlands throughout the first half of the Holocene in this region. The importance of the pine woods in the region enables us to show the clear difference in vegetation between the western and eastern parts of the Sistema Central mountains for the early to mid Holocene. Moreover, the Fagus pollen found at Valdojos, dating to ca. 7,000–6,600 cal years bp, is the oldest beech record for the central and eastern part of this chain of mountains during the Holocene. This supports the hypothesis of the existence of beech refuges in the Sistema Central for this time span. Furthermore, we used the tree-ring series from the Pinus cf. sylvestris subfossil wood from the Sandria site to extend the previous data from the Sierra de Ayllón to almost the entire Holocene. This tree-ring record is the most complete data set from the Iberian Peninsula and southern Europe and it also provides data on some aspects of the palaeoenvironment. [ABSTRACT FROM AUTHOR]

The pieces of wood extracted by the Marquis of Cerralbo at the Acheulian site of Torralba constitute one of the few materials from this famous locality that have not been subjected to detailed study by researchers. Over a century after their extraction, the present paper provides the first anatomical results of these 34 woody remains. The results highlight the presence of the taxon Pinus sylvestris – nigra group ( Pinus cf. sylvestris) at the site, thus constituting one of the few and oldest references attributable to the aforementioned taxon for the Iberian Peninsula. The anatomical diagnosis confirms the existence of Middle Pleistocene landscapes with pine woods at elevations at least 200 m lower than at present in the site area. From a taphonomic point of view, the wood samples exhibit the typical morphologies of woody macroremains preserved in continental sedimentary environments, and there was no evidence at all that they had previously been manipulated by man. [ABSTRACT FROM AUTHOR]

Abstract: The sediments of La Rinconada mine (Ribesalbes-Alcora basin, Province of Castellón, Eastern Spain) have yielded one of the Early Miocene''s richest megafloral assemblages in the southwestern Mediterranean. At this site, we have found a large amount of leaf compressions and impressions without preserved cuticle. We have identified a total of 31 species of vascular plants: 1 horsetail, 1 fern, 4 conifers, 23 arboreal or bushy dicotyledoneous angiosperms and 2 monocotyledoneous angiosperms. These fossils reveal the presence during the first half of the so-called Miocene Climatic Optimum of a fluvial-lacustrine flora with well diversified mixed broadleaved deciduous and coniferous taxa. Arctotertiary elements dominate the assemblage, whereas Palaeotropical taxa scarcely occur. The occurrence of Trigonobalanopsis exacantha and Trigonobalanopsis rhamnoides is conspicuous as these are common in humid subtropical evergreen vegetation during the climatic optima in the European Oligocene and Miocene. In the La Rinconada outcrop, there is a noteworthy lack of some taxa such as Juglandaceae, Nyssa and Quercus in comparison with other contemporaneous European floras. [Copyright &y& Elsevier]

Abstract: The native or allochthonous nature of certain extant species of the Iberian Peninsula is a matter of some controversy given our lack of knowledge regarding the survival and extinction processes to which they have been subject. The aim of the present work is to provide a review of the current knowledge regarding these processes during the Quaternary. The Middle Pleistocene Transition was a period of noticeable disappearance of Arctotertiary taxa in the Iberian Peninsula, related to the alteration in glacial cyclicity and climate change, including an increase in the severity of glaciations, a reduction in the length of the interglacial periods, and increased dryness during the coldest times. It is difficult to maintain that human activities played any important part in the complete or near-complete disappearance of some taxa during the Quaternary. In the Late Pleistocene and Holocene, however, the extinction of Cedrus, Picea and Carpinus might be related to climate change, competition with other taxa, and anthropogenic disturbances. In contrast, the extreme reduction or even complete disappearance of Platanus or Syringa seems to be due to natural causes alone. The available geological, molecular and palaeobotanical data suggest that some Arctotertiary taxa persisted over long periods of time during the Quaternary in the Iberian Peninsula. Indeed, the fossil record of one important group of taxa, including Castanea, Ceratonia, Carpinus and Juglans, shows its continued presence throughout the Quaternary. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports on analysis of plant macrofossils in aeolian deposits exposed in El Asperillo cliff in the Province of Huelva. A significant find of a large number of macrofossils of Pinus (Pinus pinaster Ait. and Pinus nigra Arnold) makes a major contribution to our understanding of the role of Pine in the Upper Pleistocene landscapes of Iberia. P. pinaster Ait. and P. nigra Arnold, are meso-microthermic species and inhabited valleys excavated in aeolian sediments mainly deposited during OIS 4 and OIS 3 (based on OSL and radiocarbon ages). Their presence in these valleys during the last part of OIS4 and OIS 3 reflects a significant fall in temperature during certain periods of these isotopic stages and helps us better understand the response of coastal dynamics to climate change. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this work is to provide a first approach to the evolution of Iberia''s vegetation during the Cenozoic (with the exclusion of the Quaternary). The Palaeogene was floristically defined by Palaeotropical elements forming tropical/subtropical rainforests, mangrove swamps, edaphically-mediated laurophyllous forests and leguminous-sclerophyllous communities. During the Miocene, Iberian landscapes were drastically modified due to geographic and climatic changes (mainly cooling and aridification) changes. Open, steppe-like environments developed towards the interior of the peninsula and Arctotertiary elements invaded mountainous and riparian ecosystems, coexisting with or becoming part of evergreen, broadleaved forests of Palaeotropical species. From the Late Miocene onwards these forests suffered changes due to the extinction of taxa, the impact of environmental change on the survivors, and the perturbations caused by the arrival of further Arctotertiary elements. However, several Palaeotropical taxa overcame the environmental and climatic changes of the Miocene and Pliocene to form a part of the modern flora of the Iberian Peninsula. [Copyright &y& Elsevier]