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Current knowledge of climate change effects on forest ecology and species conservation should be linked to understanding of the past-time. Abies pinsapo forests constitute a model of an endangered ecosystem, highly vulnerable to ongoing warming, whose populations have been declining for centuries, while the drivers of this local depletion trend remain poorly understood. We hypothesized that long-term disturbances, both human- and natural-induced, have shaped A. pinsapo forests, contributing to these decline processes. Until today, studies using fossil pollen record to identify past climate impacts and land-use changes on A. pinsapo populations have not been done. Here, we investigate forests’ dynamics since the late Holocene (1180 cal. AD to present) in Southern Iberian Peninsula from a fossil pollen record by comparing the results obtained with climate fluctuations and land-uses changes. The pollen sequence shows a phase of stability during the Islamic Period (~1180–1400 cal. AD; ‘Medieval Climate Anomaly’), followed by increasing degradation at Christian Period concurrent with ‘Little Ice Age’ (LIA) (ca. 1487–1530 cal. AD). The Modern Period (1530–1800 cal. AD; LIA) is linked to intensive forest management, related to the naval industry. Afterwards, a progressive reduction is recorded during the Contemporary Age period (‘Industrial Period’) until ‘Recent Warming’. In short, historical severe forest management coupled with increasing aridity since LIA appear to influence A. pinsapo forest current species composition and poor structural diversity. These disturbances might be limiting the resilience of A. pinsapo forests under a climate change scenario. A selected forest management could promote a more complex forest structure.

Human impact on western Mediterranean mountains is gaining more attention, as they harbour a rich plant diversity threatened by global change. This paper presents an analysis of two pollen records from both sides of Sierra Nevada, the prime plant-diversity centre of the Mediterranean, spanning the last 5400 years. The analysis sought to answer the following key questions: When did natural systems transform to cultural landscapes? What was the intensity and extent of alterations driven by the diverse civilizations? A compilation of archaeological and paleaeoclimatic data supported this analysis, as well as a multi-proxy palaeoecological study using pollen, non-pollen palynomorphs and microcharcoal, searching for the imprint that diverse societies left on these mountains. Results suggest that human influences started earlier than expected, with a strong impact on forest cover, oriented more towards crops on the southern face and towards livestock on the northern one, whereas mining and metallurgy were initial key drivers of population dynamics. Irrigation has supported farming since at least the Islamic period. More recent anthropogenic control and land-use management have allowed a further spread of the tree cover. Proper conservation strategies need long-term perspectives, including palaeoecological studies. The preservation of traditional human activities like grazing, high-elevation cropping or irrigation systems become essential to maintain current biodiversity., Departamento de Botánica, Universidad de Granada, España, Instituto de Historia, Consejo Superior de Investigaciones Científicas, España, Departamento de Biología Vegetal I, Universidad Complutense de Madrid, España, Departamento de Geografía, Urbanismo y Ordenación del Territorio, Universidad de Cantabria, Estación paleontológica Valle del río Fardes, Instituto Geológico y Minero de España, España

A new record from a long sediment core (S3) in Navamuño (1505 m asl, western Iberian Central System) provides the reconstruction of the vegetation history and environmental changes in the region between 15.6 and 10.6 ka cal BP, namely during the Late Glacial and the early Holocene, using a multiproxy analysis (pollen-based vegetation and climate reconstruction, sedimentary macrocharcoals, loss-on-ignition, magnetic susceptibility and X-ray fluorescence (XRF) measurements). The results are then compared with other sequences from the Iberian Central System and the whole Iberian Peninsula in order to better understand the past dynamics of the main forest constituents. The pollen record shows a shift from open pine forests ∼15.6–14.7 ka cal BP (Oldest Dryas) to mixed open pine-birch woodlands ∼14.7–14.0 ka cal BP (Bølling). Woodlands were succeeded by a steppe-like landscape until ∼13.4 ka cal BP (Older Dryas), which was replaced again by high-mountain pine forests and riparian woodlands ∼13.4–12.6 ka cal BP (Allerød). A great development of cold steppe grasslands linked to the decline of birch woodlands is documented ∼12.6–11.7 ka cal BP (Younger Dryas). The early Holocene (11.7–10.6 ka cal BP) was characterized by a progressive reforestation of the study area by pine and birch forests in the highlands and oak woods in the lowlands. Temperate tree taxa (Carpinus betulus, Castanea sativa, Corylus avellana, Fraxinus, Juglans, Tilia, and Ulmus) were also common but likely at lower elevations. Pollen of Fagus sylvatica was already recorded during the Late Glacial and the early Holocene. The marked increasing local fire activity during the warmer and wetter Allerød oscillation could be related to a rise in tree cover, supporting the climatically driven character of these fires. Nevertheless, the strong increase in fire activity during the Younger Dryas would probably be related to growing tree and shrub mortality, as well as to the wet/dry biphasic structure of this stadial. The standard “Modern Analogue Technique” has been also applied to the Navamuño sequence to provide quantitative climate estimations for the Late Glacial and the early Holocene periods. This record is one of the few continental archives that show the climatic trend between the Late Glacial and the early Holocene in central Iberia, agreeing with many other regional records from the Western Mediterranean.

This paper presents a palynological study of the archeological layers from the Neanderthal site Abrigo 3 del Complejo del Humo, in southern Spain (Málaga), with the aim of reconstructing the environmental conditions in the vicinity of this hominin site. The Upper Pleistocene vegetation and its variability are described, revealing a high diversity of thermophilous plant taxa throughout the cold dry phases, together with a long-term persistence of woody taxa, including Mediterranean, mesophytes, xerothermics and conifers. With the pollen records of Maytenus senegalensis as an outstanding finding, this study demonstrates the co-existence of temperate, Mediterranean and Ibero-Maghrebian angiosperms on the southern coastal plains of the Iberian Pleistocene where Neanderthals survived for a long time. It is therefore clear that Neanderthals and early Upper Paleolithic modern humans lived in a litoral refugium, which was a propitious environment for maintaining a high biodiversity, including potentially edible plant species. Besides, this coastal refugium offers broad possibilities for hunting, and interpopulational relationships through coastal platforms., The research of this work was funded by the projects MED-REFUGIA-RTI2018-101714-B-I00 (Plan Nacional I + D + I, Spanish Ministry of Economy and Competitiveness) and by the ERC-Starting Grant Proposal No. 805478. The development of this work was supported by Project (CGL-BOS2015-68604-P), funded by: FEDER/Ministry of Science and Innovation - Agencia Estatal de Investigación, Project (PID2019-1049449GB-I00), funded by: FEDER/Ministry of Science and Innovation - Agencia Estatal de Investigación and Fundación Séneca (grant number 20788/PI/18). Reyes Luelmo Lautenschlaeger is funded by a FPU contract (Spanish Ministry of Education, Culture and Sports). FPU16/00676.

Long-term fire ecology can help to better understand the major role played by fire in driving vegetation composition and structure over decadal to millennial timescales, along with climate change and human agency, especially in fire-prone areas such as the Mediterranean basin. Investigating past ecosystem dynamics in response to changing fire activity, climate, and land use, and how these landscape drivers interact in the long-term is needed for efficient nature management, protection, and restoration. The Toledo Mountains of central Spain are a mid-elevation mountain complex with scarce current anthropic intervention located on the westernmost edge of the Mediterranean basin. These features provide a perfect setting to study patterns of late Holocene fire activity and landscape transformation. Here, we have combined macroscopic charcoal analysis with palynological data in three peat sequences (El Perro, Brezoso, and Vi&ntilde, uelas mires) to reconstruct fire regimes during recent millennia and their linkages to changes in vegetation, land use, and climatic conditions. During a first phase (5000&ndash, 3000 cal. BP) characterized by mixed oak woodlands and low anthropogenic impact, climate exerted an evident influence over fire regimes. Later, the data show two phases of increasing human influence dated at 3000&ndash, 500 cal. BP and 500 cal. BP&ndash, present, which translated into significant changes in fire regimes increasingly driven by human activity. These results contribute to prove how fire regimes have changed along with human societies, being more related to land use and less dependent on climatic cycles.

[EN] The northwest region of the Iberian Peninsula is home to a unique ecosystem of bogs, which are particularly sensitive to projected climate change. In this context, the rate of carbon (C) accumulation in Chao de Veiga Mol, an intact raised bog, was analysed. Changes in the accumulation rate over the past 10 millennia were determined in a peat core of 847 cm in depth, with a high mean rate of peat growth (11 yr cm1, 0.09 cm yr1). An age-depth model was generated from 22 14C dates and fallout radionuclides. Chronological, stratigraphical and physico-chemical data confirmed the existence of a single cycle of peat formation throughout the Holocene and the formation of ombrotrophic peat 9500 years ago. The total mean C content was 50.2%, and over 10 millennia 583 kg C m2 accumulated at a mean rate of 35.3 g C m2 yr1, with a long-term (apparent) rate of carbon accumulation in the catotelm of 59.9 g C m2 yr1. These values are much higher than reported for other Iberian peatlands and are amongst the highest documented for peatlands in the northern hemisphere. The dynamics of C accumulation and other measured parameters reveals important variations throughout the Holocene. They could be associated with the main climatic events described in the northern hemisphere and are highly consistent with models established for northern latitudes. The Chao de Veiga Mol raised bog is unique and of great potential value for carrying out high resolution palaeoenvironmental studies, especially in relation to regional and local modulations in southern Europe, Los autores agradecen a la comunidad de Santo Tomé de Recaré por permitirnos llevar a cabo esta y otras investigaciones en su propiedad, y a todos los que participaron en el trabajo de campo . Esta investigación fue posible gracias a la recepción de una subvención otorgada por la Xunta de Galicia (proyecto: INCITE09-200-019-PR). Los autores desean agradecer el uso de las instalaciones analíticas RIAIDT-USC y al Prof. Geoff Millward (Universidad de Plymouth) por su ayuda con el espectrómetro gamma . También agradecemos a Christine Francis, traductora nativa, por la revisión y corrección del manuscrito en sus aspectos lingüísticos.

Knowledge of the current status of Fagus sylvatica in the Western Pyrenean Region (Northern Iberian Peninsula) is based on its widespread presence in mountain areas. However, the past evolution of this taxon and its links to natural and anthropogenic activities is not well defined. We have compiled all the published palaeobotanical data (macro and micro remains) on this region, including both natural and archaeological deposits and with particular emphasis on available radiocarbon dates. To support our analysis of the evolution of F. sylvatica, we present the palynological study of a new sequence (Gesaleta, Navarre), covering the last 11,400 cal yr BP. The main results of this paper suggest the ancient presence of F. sylvatica in the Western Pyrenean Region from at least the Late Pleistocene and Early and Middle Holocene, with a clear expansion from ca 4,500–3,500 cal yr BP, although with some regional differences. This was the point when European beech became one of the main actors in mountain forests, where it has been exploited for a variety of anthropogenic activities, Mónica Ruiz-Alonso and Sebastián Pérez-Díaz are funded by the Programa Estatal de Promoción del Talento y su Empleabilidad en I + D + i (Juan de la Cierva).

This paper presents the archaeobotanical and archaeozoological data of the 6th to 4th millennia cal BC sequence recently documented at Dehesilla Cave, and puts forward an interdisciplinary approach to the significant ecological patterns from this key archaeological site in the Southern Iberian Peninsula throughout the entire Neolithic period. Results indicate an ecological scenario characterised mainly by oak and wild olive forests, and human populations with agricultural practices and herds of mainly sheep and goats. However, this general panorama must have undergone several remarkable fluctuations. The first Neolithic populations of Dehesilla Cave, dated around the mid-6th millennium cal BC and linked to the Mediterranean impressa pottery complex, do not yet display evidences of agriculture, while all of the subsequent Early Neolithic levels indicate a model of small-scale populations with a mixed economy but still with a greater component of livestock. The second quarter of the 5th millennium cal BC shows a marked accentuation of the monoculture of naked wheats, which could have been related to the transition from an intensive to an extensive farming system. This may have entailed a selective pressure on the environment, leading to a large deforestation spanning the second half of the 5th millennium cal BC and the constitution of relatively open thermo-Mediterranean forests with a physiognomy similar to that of the dehesa. These ecological patterns are discussed within a review of the current state of the art of the use of plant and animal resources by the Neolithic human populations in the southern regions of the Iberian Peninsula.

The Toledo Mountains are a mid-elevation mountain range that separates the Tagus and Guadiana basins in the central area of the Iberian Peninsula. The location of these mountains allows the development of typical Mediterranean vegetation with some Atlantic influence. Consequently, typical broadleaved evergreen Mediterranean vegetation currently dominates the regional landscape, with the remarkable presence of more mesophilous species in sheltered and more humid microsites such as gorges (e.g., Prunus lusitanica, Taxus baccata, Ilex aquifolium) and mires/bogs (e.g., Betula pendula susbp. fontqueri, Erica tetralix, Myrica gale). Palaeoecological studies in these mountains are essential to understand the long-term ecology and original distribution of these valuable communities and are key to assess their resilience. Understanding the hazards and opportunities faced in the past by the plant communities of the Toledo Mountains is necessary to enhance the management and protection of those species currently threatened. This study focuses on El Perro mire, a peatland on the southern Toledo Mountains (central Spain) where climatic variability has played a major role in landscape dynamics at multi-decadal to millennial timescales. Climatic events such as the 4.2 ka cal. Before Present (BP) or the Little Ice Age triggered relevant landscape changes such as the spread and latter decline of birch and hazel forests. Human communities also seemed to be affected by these events, as their resilience was apparently jeopardized by the new climatic conditions and they were forced to find new strategies to cope with the new scenarios., This research was funded the project REDISCO-HAR2017-88035-P (Plan Nacional I+D+I, Spanish Ministry of Economy and Competitiveness). Reyes Luelmo Lautenschlaeger is funded by a FPU contract (Spanish Ministry of Education, Culture and Sports).

Mid-mountain ecosystems provide a broad diversity of resources, heterogeneous relief, and a mild climate, which are all very useful for human necessities. These features enable different strategies such as the terracing of the slopes as well as wide crop diversification. Their relations lead to a parallel co-evolution between the environment and human societies, where fire and grazing become the most effective landscape management tools. This paper presents the results obtained from a multi-proxy study of the Bermú paleoenvironmental record, which is a minerotrophic mire located in the Quintos de Mora National Hunting Reserve (Toledo Mountains, central Spain). The bottom of this core has been dated in the Islamic period (ca. 711–1100 cal AD), and the study shows how the landscape that was built over time in the Toledo Mountains up to the present day is narrowly linked to human development. This study shows the increasing human pressure on the landscape, as well as the subsequent strategies followed by the plant and human communities as they faced diverse environmental changes. Thus, it is possible to attest the main role played by the humans in the Toledo Mountains, not only as a simple user, but also as a builder of their own reflexion in the environment., This research was funded the project REDISCO-HAR2017-88035-P (Plan Nacional I+D+I, Spanish Ministry of Economy and Competitiveness). Reyes Luelmo is funded by a FPU grant (Spanish Ministry of Education, Culture and Sports)., This publication was funded by the Laboratorio di Palinologia e Paleobotanica—CEA 2018 Award for the oral presentation titled ‘A mid-mountain landscape shaped during fourteen centuries in the heart of Toledo Mountains (central Iberia).

Cedrus atlantica (Atlas cedar) is a relict and endemic endangered species from northwestern African mountains, whose distribution range has undergone a dramatic reduction over recent decades. Long-term studies are needed for a better understanding of the development of its range as well as for assisting in the implementation of sustainable conservation measures. The multi-proxy analysis of a high-resolution fossil record of 180 cm depth allowed us to depict the final demise of an Atlas cedar population from the western Rif Mountains (Jbel Khesana), despite its high resilience during the last ~4000 years. Currently, Atlas cedar trees are not observed in Jbel Khesana but they still occur in the nearby area as scattered populations on a few mountain tops at altitudes higher than 1400 m a.s.l. Our data show an initial relatively stable period (~4000¿2400 cal. yr BP) followed by a phase where both climatic and human-induced disturbances cause an alternate dominance of oaks and Atlas cedars (2400~1550 cal. yr BP). Then, the increasing aridity and human activities favoured the depletion of Atlas cedar forests (~1550¿800 cal. yr BP). Our record shows that Atlas cedar forests have recovered after each deforestation event, which reveals a high resilience of the species until the mid-20th century, when they became extinct in the study area. The main driver of their local extinction may be attributed to the strong human pressure. Management measures of Atlas cedar in the Rif Mountains should aim at limiting intensive loggings and protecting the existing populations for their local regeneration.

[EN] The study of the Neolithic in the Levant of the Iberian Peninsula has a long research trajectory, being well known in some river valleys such as Serpis or Clariano. The excavation of a large number of cave and open-air deposits has made this area an outstanding reference on a peninsular scale and in the western Mediterranean. However, other nearby river basins such as the Vinalopó basin have not yet had sufficient sequential bases for their characterization. The first proposals, established from the material remains found in various open-air sites and in caves, had led to consider that the process of neolithization would begin at the end of the sixth millennium cal BC, almost half a century after the presence of agricultural communities along the Serpis river. The process of Neolithic implantation in the Vinalopó had to be explained, therefore, as a result of the population expansion from the Serpis. However, new excavations and studies come to expand the range of possible explanations. Regarding the archaeological evidence documented during the excavations at Cova dels Calderons (La Romana, Alicante), we present new data, especially sedimentological, paleobotanical, archeozoological and new absolute dates. These allow us to reflect on the neolithization process of the territories in the Southern Valencian region, specifically in the Vinalopó river basin. These data make possible to formulate a new hypothesis which considers that the presence of Neolithic groups in that territory would occur much earlier than it was considered to date. This hypothesis leads us to two new possible scenarios: either the arrival of the first Neolithic groups to the northern areas of Alicante occurred in earlier times, or the origin of the first Neolithic populations in the southern areas of Alicante is not what it has been thought to date –northern basins such as the Serpis river one–. Considering this, the southern route to access these areas seems the most possible option., [ES] El estudio del Neolítico en el Levante de la península Ibérica cuenta con una larga trayectoria investigadora, siendo bien conocido en algunos valles como el Serpis o el Clariano. La excavación de un buen número de yacimientos en cueva y al aire libre ha posibilitado que esta zona sea un referente destacado a escala peninsular y del Mediterráneo occidental. Sin embargo, otras cuencas fluviales muy cercanas como la del río Vinalopó no han contado hasta el momento con suficientes bases secuenciales para su caracterización. Las primeras propuestas, establecidas a partir de los restos materiales hallados en diversos yacimientos al aire libre y en cueva, habían llevado a considerar que el proceso de neolitización se iniciaría a finales del VI milenio cal BC, casi medio siglo después de la presencia de comunidades agrícolas a lo largo del río Serpis. El proceso de implantación neolítica en el Vinalopó debía explicarse, por tanto, como resultado de la expansión poblacional desde el Serpis. Sin embargo, nuevas excavaciones y estudios vienen a ampliar el abanico de posibles explicaciones. Así, a propósito de las evidencias arqueológicas documentadas en la excavación de la Cova dels Calderons (La Romana, Alicante), se exponen nuevos datos sobre la ocupación neolítica, en especial sedimentológicos, paleobotánicos, arqueozoológicos y nuevas dataciones absolutas, que permiten reflexionar sobre el proceso de neolitización de las tierras meridionales valencianas y, más en concreto, de la cuenca del río Vinalopó. Ello permite configurar una nueva hipótesis que viene a considerar que la presencia de grupos neolíticos en dicho territorio es más antigua que lo planteado hasta la fecha. Esta hipótesis, a su vez, lleva a inferir dos nuevos escenarios posibles: o bien, que el momento de llegada de los primeros grupos neolíticos a las tierras del norte de Alicante fue más antiguo de lo propuesto, o bien que la procedencia planteada para las primeras poblaciones neolíticas del sur de Alicante no sea la hasta ahora considerada –origen en cuencas más septentrionales como la del Serpis–, siendo la vía sur la más probable., [EU]Iberiar penintsulako Levante aldean Neolitikoaren azterketak ibilbide luzea du ikerketari dagokionez, eta oso ezagunak dira haran batzuk, hala nola Serpis edo Clariano. Leizean eta aire zabalean aztarnategi kopuru handia induskatu direnez, eremu hori erreferente nabarmena da penintsula mailan eta mendebaldeko Mediterraneoan. Hala ere, oso gertu dauden beste ibai-arro batzuetan, Vinalopó ibaian, esaterako, ez dira orain arte karakterizatu ahal izateko nahikoa oinarri sekuentzial bildu. Aire zabalean eta leizean dauden aztarnategi ugaritan topatutako hondakin material ugaritatik abiatuta egindako lehen proposamenen arabera, uste izan da neolitizazio-prozesua cal BC VI milurte amaieran hasiko zela, Serpis ibaian zehar nekazaritzako komunitateen presentzia baino ia mende erdi geroago. Vinalopóko ezarpen neolitikoaren prozesua, beraz, Serpisetik populazioa zabaldu izanaren ondorioa dela uste da. Baina egindako indusketa eta azterketa berriek azalpen posibleak ugaritu dituzte. Hala, Cova dels Calderons-eko (La Romana, Alacant) indusketan dokumentatutako ebidentzia arkeologikoak direla eta, okupazio neolitikoaren inguruan datu eta datazio absolutu berriak agertu dira, bereziki sedimentologikoak, paleobotanikoak eta arkeozoologikoak. Horrek guztiak Valentziako hegoaldeko lurretako, eta zehatzago, Vinalopó ibai-arroko neolitizazio-prozesuari buruz hausnartzea ahalbidetzen du. Hala, hipotesi berri bat eragin du: lurralde horretan talde neolitikoen presentzia izan zitekeen orain arte planteatutako data baino lehenagotik. Hipotesi horrek, era berean, bi egoera posible berri dakartza: alde batetik, lehen talde neolitikoak Alacant iparraldera proposatutako data baino lehen iritsi izana, edo beste alde batetik, Alacant hegoaldeko lehen populazio neolitikoetarako planteatutako jatorria ez izatea orain arte kontuan hartutakoa (iparralderago dauden lekuetatik etorri izana, adibidez Serpisetik), eta hegoaldeko bidea izatea probableena.

The study of anthropogenic activities in prehistoric landscapes has increased greatly in recent decades in theNorthern Iberian Peninsula, particularly through pollen records from low altitude areas where settlement wasmore frequent throughout Prehistory. However, little is known about the evolution of landscapes in highlands,particularly in the Basque-Cantabrian mountains (Northern Iberia). In this paper, we analyze human dynamics inmountain landscapes through the multiproxy analysis of Arbarrain mire from c. 8200 cal BP. Obtained mainresults show the predominance of deciduous forests in the whole sequence, with presence of pinewoods at aregional scale. Thefirst evidence of anthropization of mountain environments is dated c. 6800 cal BP, in relationwith the early Neolithic. During the Mid-late Neolithic evidences of human impact on the landscape increases inparallel to the development of the megalithic structures. The Chalcolithic shows a decrease in the anthropogenicactivities in mountains. Finally, during the Bronze Age, Iron Age and Historical Period, from c. 4000 cal BP,mountain ecosystems reflect the expansion ofFagus, clearly linked with a further increase in human activity,origin of current landscape configuration.

Quantifying and reconstructing past vegetation changes is an important step to fully understand human-environment interactions in the past. In this study we present a reconstruction of arboreal cover of six studysites in the Gredos Range (central Spain) over the last 3000 yr based on multivariate statistical analysis (clusteranalysis and non-metric multidimensional scaling, NMDS) of 186 modern pollen samples, modern vegetationdata and six detailed fossil pollen records. The integrated approach allows distinguishing eight modern vegeta-tion communities and linking the fossil pollen records with these vegetation communities as modern analogues.The information of the arboreal cover of the modern pollen sites was used to estimate the past arboreal cover ofthe fossil pollen sites in the Gredos Range. This estimated arboreal cover shows a higher level of landscape open-ness than suggested by the original pollen percentages data. Our results show that the evolution of the arborealcover through time differs along an altitudinal gradient, with a decrease in arboreal cover during the Roman andVisigoth periods (2000–1240 cal BP) at low altitudes and only during the Christian/Feudal period (850–500 calBP) at high altitudes. The applied methodology, integrating fossil pollen data with modern pollen and vegetationdata in one NMDS, allows reconstructing past arboreal cover in a quantitative way., This work was supported by the projects Desirè-HAR2013-43701-P(Plan Nacional I + D + I, Spanish Ministry of Economy and Competi-tiveness) and Relictflora-P11-RNM-7033 (Excellence Research ProjectsProgram from the Andalusian Government), and partly supported bythe Interuniversity Attraction Poles Program IAP 07/09 initiated by theBelgian Science Policy Office.

Pollen analyses supported byfifteen AMS14C dates from Fuente de la Leche (1382 m) and Fuente del PinoBlanco (1343 m) peat sequences, in the Gredos range (central Spain), are used to reconstruct the lateHolocene vegetation history in this mountain region. These results are compared with other sequencesfrom the Spanish Central System in order to better understand the past dynamics of the main forestconstituents and to provide a critical view of the dialectic between conifers and deciduous forests. Thevegetation record at Fuente de la Leche starts at 3000 cal yr BP, with the occurrence of rather closedforests composed ofPinus sylvestrisandBetula.Pinus sylvestriswas the dominant pollen taxa for almostthe entire period. However, during the last 850 years,Pinus sylvestrisforests were progressively replacedbyQuercus pyrenaicawoodlands and grasslands, as a result of a high pastoral pressure, until formingmixed woodlands ~400 years ago. The interpretation of Fuente del Pino Blanco record is that dramaticchanges started about 265 years ago. Prior to this date, an open canopy woodland included species (Alnusglutinosa,Quercus pyrenaica) whose distributions no longer exist in the studied area. We suggest that theincrease in agricultural (rye and other cereals) and livestock activities forced a change in the role offire inthe supramediterranean belt of the Gredos range, thus Pyrenean oak canopy was consumed byfires,providing openings forPinus pinasterand broom communities better adapted tofire.

BACKGROUND: High-mountain pine forests and broom communities in central Spain today have led to contrasting interpretations of their natural or human-induced origin. AIMS: We evaluated the vulnerability and resilience of high-mountainPinus sylvestris/P. nigra forests and derivedCytisusbroom scrub communities to climate and anthropogenic disturbances. METHODS: We assessed historical transitions from forest to scrub and their relation to climate and human influences, using a multi-proxy paleoenvironmental study (pollen, non-pollen palynomorphs, charcoal, magnetic susceptibility) in three mires in the Gredos Range, western Iberian Central System. RESULTS: High percentages of Pinus sylvestris/nigrapollen and the identification of their macro remains demonstrated that high-mountain pine forests have been present in the oromediterranean bioclimatic belt of the Gredos Range since the mid-Holocene. After that, a major human-induced decline, enhanced by climate conditions, has led to their gradual replacement by broom communities. CONCLUSIONS: Broom communities are derived from ancient pine forests that were intensively transformed by human activities after 700 cal year BP, and largely disappeared byca. 500 cal yr BP. Today’s landscape, dominated by broom scrub and grasslands with scattered stands of pines, shows high resilience and provides suitable refugia for a rich mountain biodiversity which deserves a further protection.

Aralar is a karstic mountainous landscape situated to the south of the western-most part of the Pyreneeswhere, apart from forests, mountain pastures are very important. We have found evidence of seasonalshepherds' settlements from the Neolithic to the present in the form of megaliths, caves and foundationsof dwelling huts dating from the Bronze Age, and confirmed by radiocarbon dating. Pastoralism, apartfrom gathering and some hunting, enables the use of resources in these areas. The environmental,cultural and economic conditions determine the characteristics of the animal herds here. Thus, mountainareas are used in summer, when grass and nutritional resources are good but, when lignification in-creases, the livestock is moved lower down the valleys. More than two decades of archaeological researchin this landscape has helped to understand the shepherds' way of life over time.

This paper describes the patterns and processes of vegetation change and fire history in the Late Holocene (c. 3,140 cal BP) palaeoecological sequence of El Tiemblo, in a mountainous area in central Spain (Gredos range, Spanish Central System), and provides the first Iberian pollen sequence undertaken within a Castanea sativadominated woodland. These new data reassess not only the autochthonous nature of the species in the region and in the Iberian Peninsula, but also the naturalness of well-developed sweet chestnut forests. The study focuses on anthropogenic dynamics linked both to the effects of livestock husbandry and the use of fire for forest clearance. With this aim, non-pollen palynomorphs (coprophilous fungi ascospores) and charcoal accumulation rate are useful indicators for assessing the increasing role of human influence on vegetation, We sincerely thank three anonymous reviewers and the editor for their constructive suggestions and comments. This work was funded by the project HAR2013-43701-P (Spanish Economy and Competitiveness Ministry) “Dinámicas socio-ecológicas, resiliencia y vulnerabilidad en un paisaje de montaña: el Sistema Central (9,000 cal BC-1850 cal AD) (DESIRÈ)”. J.A. López-Sáez is currently supported by a research Grant (Spanish Ministry of Education, Culture and Sport) at Caen Basse-Normandie University. We are grateful to A. López Andreu (RIP) and P. Sáez Navas for their collaboration and assistance during the field work.

The Verdeospesoa mire is located in the Basque Mountains (Basque Country, Northern Iberian Peninsula, Spain) on the western slopes of the Gorbeia Mountain (43° 03ʹ 18ʺ N, 2° 51ʹ 41ʺ W, 1015 m above...

This contribution was financed through Projects Desirè-HAR2013-43701-P of the R&D Plan of the 165 Spanish Ministry of Economy and Competitiveness and Relictflora-P11-RNM-7033 Excellence Research Projects Programme from the Andalusian Government, Sevilla, Spain.

This paper focuses on pollen, spores, non‐pollen palynomorphs (NPPs) and certain geochemical elements from the ombrotrophic blanket bog of Zalama (Basque‐Cantabrian Mountains, northern Iberian Peninsula), with the support of a robust chronology based on 17 AMS 14C dates. The main results related to the last 8000 years show that, during the early middle Holocene, pines and deciduous forests were the most extensive tree formations. At the beginning of the succession, pines reach 44%, showing regional presence, whereas after 7600 cal. a BP, deciduous forests were particularly abundant. From c. 6500 cal. a BP the pollen diagram constructed from our samples shows the first anthropogenic evidence, linked with the new economic practices related to the Neolithic of the Basque‐Cantabrian Mountains. From 3300 cal. a BP the expansion of Fagus sylvatica is particularly clear, and has since then become one of the dominant forest species in this region. We also discuss the Holocene evolution of other noteworthy plant communities in southwestern Europe, such as Taxus baccata, Juglans and shrublands., S. Pérez‐Díaz is currently supported by a postdoctoral research grant (Basque Government) and is part of the Research Group in Prehistory IT622‐13/UFI 11‐09 of the University of the Basque Country (UPV/EHU) and Project HAR2011‐23716 (Nuevos cultivos, nuevos paisajes), funded by the Plan Nacional I+D+I

In this paper we present a review of the available Holocene pollen records from the Spanish Central System (113 sites and 150 14C dates). Palynological data obtained from pollen analyses of peat-bogs, lakes and archaeological sites, as well as radiocarbon dating, were used to infer the human impact on vegetation and landscape during the last 9 millennia. The Neolithic contribution to the configuration of landscape is scarce, limited to the valleys, while Chalcolithic settlements and their related activities (agriculture and grazing) represent the first evidence of significant human impact on the high-mountains. The pollen record has allowed us to relate two cultural periods of changing, the Copper Age–Early Bronze Age and Late Bronze Age–Early Iron Age transitions, to abrupt climate disruptions, the so-called 4.2 and 2.8 ka cal BP events respectively. From the Iron Age to the Early Middle Ages, anthropic activities were still sporadic, mainly located in the lowlands, but from the Feudal Period onwards, when La Mesta transhumance system takes place, high-mountain landscapes changed dramatically. Late Modern Period brings a further intensification of human pressure, especially related to forestry, with widespread pinewood afforestation., We are indebted to the CONSOLIDER-INGENIO 2010 Program (CSD2007-00058), EXCELENCIA 2011 Program (RNM-7033) and AGRIWESTMED (ERC-Advanced Grants, proposal n° 230561)