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Este trabajo pretende analizar la construcción de los paisajes medievales en el Sur del Duero. La imagen que se ha elaborado desde los estudios centrados en el registro escrito enfatizan un incremento de la actividad agraria a partir del siglo XII, como consecuencia de la repoblación. Sin embargo, el análisis del caso de Monleras, una población situada en la comarca de la Ramajería (Salamanca) revela una situación más compleja. Mediante el estudio combinado del registro escrito, de los datos arqueológicos y de dos análisis paleopalinológicos sobre sendos bonales, se ha podido reconstruir una evolución distinta. Estos espacios evidencian una ocupación antrópica desde finales del siglo IX y en el siglo X, cuando se había producido aparentemente un cambio en los patrones de asentamiento que habían definido a los siglos posromanos. Por otro lado, se produjo una transformación con una intensificación de la cerealicultura desde comienzos del siglo XII, aprovechando las favorables condiciones medioambientales que habían generado los humedales. En la Baja Edad Media y a comienzos del periodo moderno, los humedales se fueron progresivamente secando, dando lugar a un paisaje de dehesa, que ha caracterizado tradicionalmente a esta comarca. Estos cambios fueron efectuados por la población local, sin que hubiera una injerencia externa (señorial o del poder urbano) y posiblemente como parte de una acción colectiva. Se puede concluir el importante papel de la resiliencia de los habitantes ante los cambios sociales y medioambientales. Aunque estos datos se refieren a un caso de estudio específico, implican la necesidad de profundizar en la agencia local y en el dinamismo en los procesos de construcción de los paisajes medievales., This paper aims to analyze the construction of medieval landscapes in the southern Duero plateau. The image created by the studies focused on written records emphasizes an increase in agricultural activity from the 12th century, as a consequence of the so-called repoblación (repopulation). However, the analysis of the case-study of Monleras, a village located in the region of La Ramajería (Salamanca), reveals a more complex situation. Thanks to the combined study of written records, archaeological data and two palaeopalynological analyses on two bonales (wetlands), a different view of the evolution of those landscapes has been proposed. These areas show an anthropic occupation since the end of the 9th century and during the 10th century, when there had apparently been a change in the settlement patterns that had defined post-Roman centuries. There was also a transformation defined by the intensification of cereal farming since the beginning of the 12th century, which took advantage of the favourable environmental conditions generated by the wetlands. In the Late Middle Ages and the beginning of the early modern period, the wetlands gradually dried up, creating a dehesa (a landscape defined by the presence of holms and oaks in the clearings, which is a traditional feature of region). These changes were made by the local population, without external interference (of lords or towns) and possibly as the consequence of a collective action. We can therefore suggest that the inhabitants’ resilience to social and environmental changes played an important role. Although these data refer to a specific case study, they involve the need to delve into the local agency and into the dynamism of the processes of construction of medieval landscapes.

Research in the Guadalquivir estuary and its environs has revealed evidence of a periodic succession of extreme-wave events in the area from the third millennium BC to the third century AD. Return periods range from 400 to 800 years. Some of these extreme-wave events may have had a magnitude comparable with that of the so-called “Lisbon earthquake” of 1755. Contrary to the tenets of the uniformitarian paradigm in geology—still influential in the archeological literature—these events had short-, mid-, and long-term geomorphological and paleo-environmental, as well as immediately destructive and demographic, effects. Attention should also be called to the reverberations of these events in the cultural development of southwestern Iberia, which is independently known for puzzling interruptions, recommencements, and transformations every few centuries from the Neolithic to the Roman period. The two records, natural and cultural, might be connected. In study areas with a compelling historical and archeological heritage, such as western Andalusia, there is a need for multidisciplinary projects that, by bringing geology and biology to bear on archeology and history, aim to accurately establish the succession of geographical and environmental transformations, the impact of these transformations on the area’s cultural history, and the chronology of the events.

La diversidad vegetal de Sierra Nevada es resultado de múltiples procesos que han determinado que se haya producido la sucesión continuada de contingentes florísticos y comunidades vegetales de diverso origen a lo largo de su historia geológica. Gran parte de la flora actual de Sierra Nevada proviene de latitudes septentrionales de Europa ( elementos arctoterciarios), cuando aún los materiales que dieron lugar al macizo nevadense estaban unidos al este de la placa ibérica en el Oligoceno, lejos de su emplazamiento final al sur de Iberia. A finales de este período, y durante todo el Mioceno, el clima inicia una tendencia hacia la aridez y enfriamiento global que provoca la extinción de parte de la flora paleotropical de Iberia, y su progresiva sustitución por la flora arctoterciaria. Es cuando la vegetación del sureste peninsular se enriquece en elementos sabanoides, quedando relegados los bosques siempreverdes y semideciduos a las zonas de mayor disponibilidad hídrica. La alta montaña nevadense es ocupada por cinturones de coníferas, mientras que por la franja costera y lagunas salobres se distribuyen los manglares. La desecación parcial del Mediterráneo durante la crisis del Messiniense promueve la creación de puentes que constituyen importantes rutas migratorias para especies irano-turánicas y saharo-síndicas. Tras la apertura del Estrecho de Gibraltar en el Plioceno, se consolida la estacionalidad propia del clima mediterráneo, que dio lugar a una vegetación muy similar en estructura a la actual. Finalmente, el Cuaternario supone la culminación del lento proceso de enfriamiento iniciado en el Terciario, durante el cual la alternancia de períodos glaciales e interglaciales proporciona refugio a táxones arctoterciarios e induce la extinción de los últimos elementos paleotropicales. La reciente recuperación climática del Holoceno supuso la expansión de bosques de frondosas del género Quercus.

A general survey of archaeological information regarding the Upper Paleolithic in the Iberian Peninsula suggests that the settlement of huntergatherers is characterized by a patchy pattern with clusters of sites in some regions and no reported settlements in others. The causes, characteristics, implications and consequences of those settlement patterns are still unclear. One of the main variables involved in this question is the relative changing climatic conditions of the Upper Paleolithic. Here we discuss the climatic conditions of the Upper Paleolithic and its influences on human behaviors in the Western Pyrenean Region (WPR, Northern Iberian Peninsula) during the Gravettian and Solutrean technocomplexes, a timeframe with several fluctuations in temperature and rainfall, leading to some cold and dry episodes followed by other more humid and temperate ones at both the Iberian and European scale.

The exceptional preservation of organic remains in a well-reservoir at the site of La Tabacalera (Asturias, Spain) is the subject of an interdisciplinary study regarding past human-environmental interaction. The feature, dated to Late Antiquity, corresponds to a large well containing a wide range of organic material (animal bones, pollen, non-pollen palynomorphs (NPPs), mites, seeds, wood and wooden artefacts, etc.). This article examines both plant micro (pollen and NPPs) and macro-remains (seeds and wood) dated between the late 5th–8th c. AD. The palynological evidence suggests that the structure investigated was colonised by different species dominated by ivy, while the surrounding anthropised area was characterised by the presence of open areas, probably occupied by meadows and pastures. A mixed deciduous forest was also present not far from the site. The abundant plant macro-remains include the presence of water-loving woody species, which inform us about the vegetation growing around the well-reservoir. The seed record comprises cultivated plants, and a wide range of wild species typical of humid environments. Among the remains there are also some wooden artefacts. Plant remains have provided significant information, not only to reconstruct the landscape around the site, but also on the formation of the feature’s backfill. Moreover, the remains offer us information regarding objects of daily life and the maintenance of the feature

Many syrphid larvae are predators of aphids and early stages of moths and psyllids, being potential control agents of some olive pests. However, adults need pollen and nectar for energy and reproduction. An increase of plant resources biodiversity in heterogeneous landscape could benefit these natural enemies. Thus, our goal of was to study the syrphid biodiversity and their pollen sources in olive agroecosystems from the northeast of Portugal during spring, that coincides with the availability of pests. For that, syrphids were captured in three not-tilled olive groves and two surrounding field areas (an herbaceous vegetation patch and a scrubland) next to each olive grove. Simultaneously, flowering plant inventories were carried out. Syrphids and the pollen contained in the guts of the most abundant species were identified. Thereafter pollen in guts was compared with pollen in the environment to evaluate a potential pollen selection. The most abundant species were Sphaerophoria scripta and Melanostoma mellinum. During the spring syrphids did not consume all the occurring plant species but did not actively selected pollen types. Results indicated that Asteraceae, Plantaginaceae, Caryophyllaceae, Echium type, Rumex type and Jasione type are important food sources for M. mellinum and S. scripta. These results will allow managing ground cover vegetation more efficiently in order to conserve syrphids in the olive agroecosystem

[EN] This article presents the results obtained from a pollen study obtained from three samples from Peña del Moro, a site assigned to the Protocogotas, Cogotas I and Soto cultures. The particularity of this study, which lies in the archaeological context of the samples, comes from two stratigraphically superimposed huts in the Bronze age- Iron age transit. A third pollen sample (dated during the Late Bronze age), completes the study, allowing to obtain a a full panoramic of the evolution of the prehistoric landscape in the Northwest of Segovia., [ES] El análisis que aquí se presenta, ofrece los resultados obtenidos de un estudio polínico realizado a partir de tres muestras procedentes del castro de la Peña del Moro, un yacimiento adscrito a las culturas Pro-tocogotas, Cogotas I y Soto inicial. La particularidad de este estudio, radica en el contexto arqueológico de las muestras, procedentes de dos viviendas estratigráficamente superpuestas en el tránsito Bronce Final- Hierro I. Una tercera muestra polínica datada durante el Bronce Medio, completa el estudio, permitiendo obtener una panorámica completa de la evolución del paisaje prehistórico en el noroccidente de la provincia de Segovia.

The aim of this work is to reconstruct the periods of growth and decline of human populations in Morocco and their potential impacts on the landscape over the past 10,000 years. In order to estimate the trends in the human population size between 10,000 and 3000 years ago, we used a summed probability distribution (SPD) of radiocarbon dates from a wide range of archaeological sites throughout Morocco. Landscape changes were identified and quantified from a dataset of fossil pollen records. Different anthropogenic pollen markers, as well as natural vegetation groups and taxonomic richness were used to analyse the relationship between long-term trends in human population expansion or regression and type of impact on the landscape. The sub-regions of Morocco have different topographies and climates, which have either favoured or prevented the establishment and/or spread of human populations. In order to identify the areas most significantly impacted by humans and the timing of such impacts, we have reconstructed and compared the same past anthropogenic and landscape proxies along with the population trends within the lowlands and mountainous areas. The lowlands were more strongly impacted earlier in the Holocene than the mountainous areas. Anthropogenic markers indicate that farming expanded in the lowlands during the first major expansion of human populations between ca. 7200 and 6700 cal. yr BP at the start of the Neolithic period. In the Atlas and Rif Mountains, anthropogenic impact is not clearly detectable in any of these areas before 4000 cal. BP.

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

Chrysoperla carnea s.l. (Stephens) larvae are important natural enemies in agroecosystems. However, adults feed on honeydew excreted by hemipterans, and pollen and nectar from flowering plants. Pollen is essential for egg production, but to our knowledge, the pollen diet of C. carnea in perennial crops has never been addressed. In this work, the objective was to study the diversity and potential selection of pollen types consumed by C. carnea in the olive grove agroecosystem. For this study, C. carnea adults were captured from April to December of 2012 and 2013, and simultaneously, inventories of the plant diversity were obtained in olive orchards and adjacent scrubland and herbaceous patches. The pollen types contained in C. carnea guts were identified by microscopy and compared with the pollen types in the environment using Jacobs`s second selection index. The results indicated that (i) C. carnea females and males captured in the olive tree canopy visited scrub and herbaceous vegetation patches; (ii) they fed on different anemophilous and entomophilous pollen types from tree and scrub (Olea europaea, Fabaceae, Pinaceae, Cistaceae or Ericaceae) and herbaceous (Asteraceae, Apicaceae, Brassicaceae, Poaceae, Rumex type or Plantago type) strata; and (iii) adults fed not only on flowers but also on pollen settled on vegetation surfaces. Here, we demonstrated that C. carnea could benefit not only from the diversity of entomophilous pollen during the plant flowering periods but also from other pollens that could remain in the environment in different periods. This has important implications for the management of the floral diversity adjacent to the crop.

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.

[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

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

The effects of climate change on forest growth are not homogeneous across tree species distribution ranges because of inter-population variability and spatial heterogeneity. Although latitudinal and thermal gradients in growth patterns have been widely investigated, changes in these patterns along longitudinal gradients due to the different timing and severity of regional droughts are less studied. Here, we investigated these responses in Mediterranean Black pine (Pinus nigra Arn.). We built a tree-ring width dataset comprising 77 forests (1202 trees) across the Mediterranean Basin. The biogeographical patterns in growth patterns and the relationships between growth and mean temperature, precipitation, drought and atmospheric circulations patterns (NAO -North Atlantic Oscillation-, SOI -Southern Oscillation Index- and MOI -Mediterranean Oscillation index-) were analyzed. Then, we evaluated the spatial and temporal growth synchrony between and within east and west populations. We found different growth and climate patterns in west vs. east Black pine populations, although in both regions growth was driven by similar temperature and precipitation variables. MOI significantly influenced tree growth, whilst NAO and SOI showed weaker effects. Growth of east and west Black pine populations desynchronized after the 1970s when several and uncoupled regional droughts occurred across the Mediterranean Basin. We detected a climate shift from the 1970s to the 1980s affecting growth patterns, changing growth-climate relationships, and reducing forest growth from west to east Black pine forests. Afterwards, climate and growth of east and west populations became increasingly more divergent. Our findings imply that integral bioclimatic and biogeographical analyses across the species distribution area must be considered to adequately assess the impact of climate change on tree growth under warming and more arid conditions.

Lake Medina is a small, shallow and endorheic salt lake sensitive to climate variation in south-western Spain, close to Cádiz in western Andalusia. It is located in an evaporitic and karstic environment, and a saline lake affected by highly seasonal precipitation and evaporation. Geochemical and mineralogical data of core CO1313 combined with a robust age model show variation that contributes to the understanding of palaeoenvironmental and palaeoclimatic change. This study shows a pollen record that has been conducted on core CO1313, together with charcoal and non-pollen palynomorph analyses. The environmental and climatological history reconstruction of Lake Medina starts in early Holocene times (at 9.5 cal. ka BP) and shows intensified pasture and land use during middle-Holocene times as well as the 8.2 and 4.2 cal. ka BP abrupt climate events. Oxidation of plant remnants and resulting non-preservation at certain times reinforces the hypothesis of intense climate effects on vegetation during the 4.2 cal. ka BP climate event. Yet, oxidation of plant residues during other episodes shows other periods that were also affected by reduced precipitation. From around 2 cal. ka BP onwards, a recent trend towards aridification and enforced seasonality was detected

[EN] Sixty modern surface samples collected from mosses in different cypress forest communities (Cupressus sempervirens L.) on the island of Crete (Greece) were analysed for their pollen content. The samples were taken from six different cypress phytosociological associations between 23 and 1600 m asl, and fall within distinct rainfall and temperature regimes. The aims of this paper are to provide new data on the modern pollen rain from the Aegean islands, and to perform these data using multivariate statistics (hierarchical cluster analysis and canonical correspondence analysis) and pollen percentages. The discrimination of pollen assemblages corresponds to a large extent to the floristic differentiation of Cupressus sempervirens forest vegetation and indicates the existence of three new associations, [ES] Sesenta muestras de lluvia polínica actual recolectadas en cepellones de musgos, procedentes de distintas comunidades de ciprés (Cupressus sempervirens L.) en la isla de Creta (Grecia), fueron analizadas palinológicamente. Las muestras proceden de seis asociaciones fitosociológicas dominadas por el ciprés entre 23 y 1600 m asl, bajo regímenes de precipitación y temperatura diferentes. El objetivo de este trabajo es prover datos novedosos acerca de la lluvia polínica actual en las islas del Egeo, así como tratar éstos mediante análisis multivariantes (análisis de cluster jerárquico y análisis de correspondencias canónicas) y a partir de sus porcentajes polínicos. La discriminación de los espectros polínicos corresponde en gran medida a la diferenciación florística de la vegetación de los bosques de Cupressus sempervirens e indica la existencia de tres nuevas asociaciones

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.

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 Viñuelas mires) to reconstruct fire regimes during recent millennia and their linkages to changes in vegetation, land use, and climatic conditions. During a first phase (5000–3000 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 3000–500 cal. BP and 500 cal. BP–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.