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Most studies on the geomorphological evolution of the Holocene from the Ebro depression (NE Spain) are focused on the period up to the Roman Epoch (218 BC–476 AD) while some references to medieval (476 AD–15th century) deposits are also occasionally dated. This paper focuses on the establishment of aggradation units on the valley bottoms and slopes of the Ebro depression after 1400 BP, their origin, comparison with other areas, and relationship with global paleoenvironmental changes. These units were produced after the incision phase that marked the end of the large Holocene accumulation (unit H1) around 1400 BP (at the end of the Late Roman Epoch). Morphosedimentary records enable us to establish three aggradation units during the last 1400 years: unit H2 (ca. 1400–650 cal BP); unit H3 – with two H3A subunits (ca. 650–500 cal BP) and H3B (ca. 500–320 cal BP); and the H4 unit (after 320 cal BP). These units are organized following five types of aggradation/incision arrangements with differing complexities. There are also connections among these units and two slope stages in the region. Finally, the genetic relationships between these units and global paleoenvironmental changes are shown (LALIA, MCA, and LIA) and related to anthropic activity. This contribution is the first detailed and systematic approach to the study of morphosedimentary units and sedimentary arrangements during the Recent Holocene in the Mediterranean area. [ABSTRACT FROM AUTHOR]

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]

The present paper deals with the historical evolution of the northern Bay of Cádiz (SW Spain) between the last eustatic maximum (6.5 ka BP) and the present day, by means of a series of independent proxies. The zone is constituted by the tidal estuary of the Guadalete River, filled with saltmarsh sediments during the late Holocene, due to the sheltering of the zone by a confining outer sandy barrier. The northern border of the Bay records an urban settlement of Phoenician Age (first millennium BC), Doña Blanca. A detailed survey was made in the contact between the Phoenician city and the saltmarshes in order to detect other possible urban structures related to the morphological and sedimentary evolution of this environment during historical times. Two campaigns with GPR Stream-X array were carried out as well as aerial imaging and topographic survey with UAV. In parallel, a total of 8 boreholes were made in different parts of the saltmarshes, including radiocarbon dating of selected samples for estimating sedimentation rates in the saltmarshes. Results obtained by georadar prospection and UAV survey revealed the presence of a second urban settlement on the marginal sedimentary plain, very probably installed upon a sandy fluvial island of the Guadelete River. The urban remains, of Punic Age, are partly covered by clay sediments due to the subsequent evolution of these saltmarshes, where sedimentation rates of up to nearly 2.4 mm/yr have been estimated for environments close to fluvial and/or tidal channels and hence more affected by sediment aggradation during flooding episodes. In recent times, river regulation by dams and the artificial desiccation and cropping of the saltmarshes have interrupted the natural trend of the area towards sedimentary silting up. [ABSTRACT FROM AUTHOR]

Environmental fluctuations during the Holocene caused important landscape changes in the Central Ebro Basin, which is a very sensitive region due to its semiarid climate, lithology, and continuous human presence. Severe erosion processes hinder palaeoenvironmental and archaeological record preservation. Infills of ephemeral stream valleys in semiarid environments are some of the best contexts for geoarchaeological studies. In this paper, we analyse the geomorphological processes, pedological features, and charcoal and pollen content and composition of the sedimentary sequence of La Poza Valley catchment area, with the support of additional information from La Bajada Valley. 14 C dates for 13 charcoal fragments provide the necessary chronological control. We describe 5 sedimentary units and a polycyclic sequence of six soils that covers most of the Holocene, beginning ca. 9.5 ky cal BP. Buried soils help to identify stability periods in the sedimentary sequence, while incision stages are detected through erosive contacts and terraced organisation of the sedimentary units. Charcoal and pollen content and composition, as well as the soil development, reveal an open forest of junipers and pines for the Early Holocene in the lower part of the sequence (mainly in Unit 1), very different from the current deforested landscape, also represented in the sequence (Unit 4). Thus, La Poza record shows the environment was favourable for hunter-gatherers from the Late Mesolithic and for the first Neolithic farmers. From then on, progressive degradation due to a combination of climate changes and increasing human pressure led to the current deforested landscape. [ABSTRACT FROM AUTHOR]

Abstract: Rodríguez-Ramírez and Yáñez-Camacho (2008), Rodríguez-Vidal et al. (2009) and Rodríguez-Ramírez et al. (2009) have kept an ongoing discussion about the validity of radiocarbon ages in reconstructing Holocene palaeogeographical models in the Gulf of Cadiz. The discussion considered the validity and correctness of the ΔR value to be used in the area to calibrate radiocarbon ages of marine samples. These papers suggest that the ΔR value proposed by Lario (1996) and Dabrio et al. (1999, 2000) is erroneous, and consequently, that all the evolutionary models based on radiocarbon ages from marine samples that have been proposed in this area since 1996 must be revised. However, the papers commented here use erroneously the R, regional R and ΔR values. After reviewing the published data, it is apparent that the most reliable values of ΔR in the Gulf of Cadiz for middle-late Holocene samples range between ΔR =35±85yr and ΔR =95±15yr. This means that the values used in Lario (1996) and Dabrio et al. (1999, 2000) fall in this range, and also that the calibrated ages used by several authors adopting these values are fully reliable. Calibrations using ΔR values inside this range do not yield significant differences in terms of geological age owing to the magnitude of errors resulting from the methods employed. [ABSTRACT FROM AUTHOR]

Abstract: This paper reviews the sedimentological and geomorphological imprints of prehistoric and historical tsunamis in the four main estuaries of SW Spain. These imprints include beach erosion, filling of intertidal channels, deposition of bioclastic layers, washover fans and reworked aeolian sheets and the breaching of spits and tombolos. Most of these imprints were caused by the 218–209BC and AD1755 tsunamis, although evidence of other tsunamis has been identified. In these two events, effects on human populations were severe and diverse, such as human loss of life, changes in coastal settlements and international borders, damage to port infrastructure or flooding of marsh and inhabited areas. New radiocarbon reservoir data were included in order to obtain an approach to the recurrence period of these high-energy events (700–1000years) in this area. [Copyright &y& Elsevier]

Abstract: Although ongoing, excavations at the Valdavara-1 cave (Galicia, northwestern Spain) have already yielded a rich and highly diverse terrestrial small vertebrate assemblage. Among the findings, two precaudal vertebrae from the Holocene level (with a radiocarbon age of 4490±40 years BP) are attributed to the golden-striped salamander (Chioglossa lusitanica) and constitute the first fossil evidence for this species. Because of the poor intraspecific genetic diversity of living Spanish populations it has been proposed that they have a recent origin linked with a postglacial expansion from southern refuges. The palaeontological data presented in this paper thus show that the northernmost expansion of the species took place at least as early as the Chalcolithic period and permit the estimation of its dispersion speed within its potential distribution area. [Copyright &y& Elsevier]

In this paper we illustrate how different internal and external forcings conditioned postglacial vegetation in southern Mediterranean areas. By comparing seven Holocene sequences, we emphasize the role of glacial refugia as postglacial vegetation dispersal centers. We also identify the importance of the system's inertia in the time lags observed for vegetation response to climate change and human pressure. Finally, we explore the cascade of effects triggered by the human-climate interface, specifically the vegetation and the environmental feedbacks implicated in the collapse of the Argaric culture that emerged in arid southeastern Spain about 4,000 years before the present. [ABSTRACT FROM AUTHOR]

A series of marked environmental changes took place during the transition from Pleistocene to Holocene, to which the hunter-gatherers adapted by modifying their technology and subsistence practices. In parallel with these changes, territoriality increased and significant transformations in artistic expression occurred. This paper assesses the archaeological record of the Iberian Mediterranean watershed to analyze various aspects. of this adaptive process, which unfolded gradually from the end of the Magdalenian to the beginning of the Neolithic. [ABSTRACT FROM AUTHOR]

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: 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]

This paper presents pollen analyses and radiocarbon dating on Crocuta coprolites from Las Ventanas (LV) and Carihuela (Car) Caves in southern Spain (Granada), with the aim of reconstructing the environmental conditions of these hominin sites. The LV coprolites are radiocarbon dated from c. 37,890 to 6980 cal yr BP, and the Car coprolites from c. 31,063 to 7861 cal yr BP. Overall, the palaeoecological scenario inferred from both coprolite series display similar patterns, with Pinus , Poaceae, and Artemisia as dominant during the full Pleistocene, and an important contribution of Quercus in the most recently dated coprolite samples. While the palynology is consistent with results of former investigations on the past environments in the region as obtained from other deposits (peat bogs, cave infills), the Late Glacial and Holocene chronology of several coprolites in both sites is in conflict with the generally accepted timing of extinction of Crocuta in western Europe. A discussion on the taphonomical processes and potential sources of carbon contamination of the radiocarbon samples is provided. The correlation between pollen from coprolites and from sedimentary records, and the paucity of the fossil bone record suggests nevertheless, that a late survival of Crocuta in southern Spain should not be categorically discarded. • New pollen analyses and radiocarbon dating on Crocuta coprolites from Las Ventanas (LV) and Carihuela (Car) Caves. • The palaeoecological scenario inferred from both coprolite series display similar patterns. • Timing of extinction of Crocuta in western Europe. • A late survival of Crocuta in southern Spain should not be categorically discarded. [ABSTRACT FROM AUTHOR]

Abstract: It is paradoxical that work in question (Rodríguez-Ramírez and Yánez-Camacho, 2008) has started a debate in the scientific community about the values of the reservoir effect used in the 14C dates in the Gulf of Cádiz, since in their Comments Rodríguez-Vidal et al. (2009), Monges Soares (2010-this issue) and Lario et al. (2010-this issue), have not taken into account that these values are in reference to earlier studies (Morales et al., 2008). The new figures suggested by Rodríguez-Vidal et al. (2009) and Monges Soares (2010-this issue) for this part of the Gulf of Cadiz (Soares, 2008) had not been reported when the earlier papers were accepted and published. The values for the reservoir effect applied on the South Atlantic coast of the Iberian Peninsula need to be continually adjusted, due to the new contributions that have been made in recent years as a result of developments of the research being undertaken in this field. Without doubt, in the future, as further progress is made, the values will be even more finely tuned and the present ones will become obsolete, as our understanding of marine and estuarine dynamics in this sector over the last few thousand years is a topic which remains open to new interpretations. The new figures for the reservoir effect are an important contribution in determining more accurately the chronology of events in the Holocene, and they make it necessary to revise the previous studies on marine Holocene formations in the Gulf of Cadiz with 14C dates, owing to the errors that have occurred in this respect. For this reason the Comment should not be aimed at one paper alone, and instead this matter should be reviewed at a regional level. Those of us who are not specialists in the topic welcome these clarifications, which can help shed additional light on the chronological problems. [ABSTRACT FROM AUTHOR]