Influence of climate change and human activities on the organic and inorganic composition of peat during the ‘Little Ice Age’ (El Payo mire, W Spain)

Acknowledgements We are grateful to Ana Moreno, Mariano Barriendos and Gerardo Benito who kindly provided us data included in Figure 5a. We also want to thank the two anonymous reviewers for their constructive comments. Funding This work was funded by the projects HAR2013-43701-P (Spanish Economy and Competitiveness Ministry) and CGL2010-20672 (Spanish Ministry of Science and Innovation). This research was also partially developed with Xunta de Galicia funding (grants R2014/001 and GPC2014/009). N Silva-Sánchez is currently supported by an FPU pre-doctoral grant (AP2010-3264) funded by the Spanish Government.Peer reviewedPostprin

Vulnerability and resilience of high-mountain pine forests of the Gredos range (Ávila, Spanish Central System): two thousand years of socio-ecological dynamics

RESUMEN: En este trabajo se presenta el análisis palinológico de la turbera de Pozo de la Nieve, localizada en el Parque Natural del Valle de Iruelas (Ávila), un área de alto valor sociocultural dentro de la Sierra de Gredos (Sistema Central). Con el objetivo de relacionar los cambios en el paisaje con la explotación de los recursos naturales y eventos climáticos, en primer lugar se han realizado 7 dataciones radiocarbónicas que sitúan el inicio del registro sedimentario ca. 240 cal BC. Los datos polínicos indican la existencia de un denso pinar altimontano dominado por Pinus sylvestris/nigra desde la Segunda Edad de Hierro hasta el periodo islámico. A partir del periodo cristiano las actividades antrópicas se intensifican, especialmente la ganadería en la Edad Contemporánea, lo cual conlleva la progresiva desaparición del pinar de alta montaña y el desarrollo de pastizales mediante el manejo del fuego, situación que culmina con el desarrollo del paisaje actual dominado por piornales pirófilos.ABSTRACT: We present the palynological study of Pozo de la Nieve peat bog, located in a very valuable socio-cultural placement within the Iruelas Valley Natural Park (Gredos range, Iberian Central System). We have focused in relating landscape changes to natural resources management and climatic events. Firstly, we carried out seven radiocarbon dates suggesting the origin of this record ca. 240 cal BC. The palynological data show the existence of dense high-mountain pine woodlands dominated by Pinus sylvestris/nigra from the Late Iron Age to the Muslim period. Later, from the Christian period, anthropogenic activities have intensified, especially livestock grazing in the Contemporary Age. Its consequences are the progressive disappearance of highmountain pine forests and the extension of grasslands by means of fire, which has shaped current landscape dominated by broom communities.Este trabajo ha sido financiado por el proyecto Desirè-HAR2013-43701-P (Plan Nacional I+D+I, Ministerio de Economía y Competitividad de España). Sebastián Pérez Díaz está financiado por el Programa Estatal de Promoción del Talento y su Empleabilidad en I+D+i en la modalidad Juan de la Cierva-Incorporación. Mónica Ruiz Alonso está financiada por el Programa Estatal de Promoción del Talento y su Empleabilidad en I+D+i en la modalidad Juan de la Cierva-Formación

Paleobiogeografía de Abies spp.y Cedrus atlantica en el Mediterráneo occidental (Península Ibérica y Marruecos)

RESUMEN: Las especies mediterráneas incluidas en el género Abies, y Cedrus atlantica presentan en la actualidad unas áreas de distribución muy limitadas.En este trabajo, se describen el origen y las rutas migratorias seguidas por Abies pinsapo, A. marocana, A. tazaotana y Cedrus atlantica, desde los inicios del Terciario hasta la actualidad, así como las posibles causas que han llevado a sus poblaciones a su estado actual de aislamiento y peligro de extinción. Abies y Cedrus habrían alcanzado el Mediterráneo Occidental junto con otros elementos de la flora arctoterciaria entre el Eoceno Medio (45 Ma) y el Oligoceno (30 Ma). Posteriormente, experimentaron procesos de especiación hasta fechas relativamente recientes, en los que la apertura del estrecho de Gibraltar (5.33 Ma) habría jugado un papel esencial. A lo largo de las glaciaciones-deglaciaciones del Cuaternario, abetos y cedros mediterráneos habrían permanecido en refugios montañosos del sur de la península ibérica y del norte de África. A pesar de presentar cierta expansión y migración altitudinal coincidiendo con el óptimo térmico del Holoceno Medio, estas especies han sufrido un notable decliveposterior de sus poblaciones, como consecuencia del incremento de la aridez y del impacto de las actividades humanas. El desarrollo de las estrategias de conservación más adecuadas requiere una mejor información sobre la respuesta de estas especies a las distintas perturbaciones, para lo cual resulta indispensable conocer su evolución a lo largo del tiempo. El registro fósil, tanto de macrorrestos como de polen junto a diversos estudios genéticos contribuyen a evaluar su resiliencia y vulnerabilidad.ABSTRACT: The Mediterranean species included in the genus Abies, and Cedrus atlantica show very limited distribution ranges at present. In this work, we outline the origin and migratory routes followed by Abies pinsapo, A. marocana, A. tazaotana and Cedrus atlantica, from the beginning of the Tertiary to the present, as well as the likely causes which have led their populations to their current state of isolation and danger of extinction. Abies and Cedrus would have reached the Western Mediterranean along with other elements of the arctotertiary flora between the Middle Eocene (45 Ma) and the Oligocene (30 Ma). They subsequently underwent speciation processes until relatively recent times, among which the opening of the Strait of Gibraltar (5.33 Ma) would have played an essential role. Mediterranean firs and cedars would have stayed in Southeastern Iberian and North African mountainous refugia during Quaternary glaciations-deglaciations. Despite a noticeable expansion and altitudinal migration in the Mid-Holocene thermal optimum, these species have experienced a further remarkable decline, as a result of the increasing aridity and pressure of human activities. The development of the most appropriate conservation strategies requires the best information on the response of these species to diverse disturbances, thus the knowledge on their temporal evolution becomes essential. The fossil record, both macrorests and pollen, contributes, along with diverse genetic studies, to assessing their resilience and vulnerability

Palaeoecological data indicates land-use changes across Europe linked to spatial heterogeneity in mortality during the Black Death pandemic

The Black Death (1347-1352 CE) is the most renowned pandemic in human history, believed by many to have killed half of Europe's population. However, despite advances in ancient DNA research that conclusively identified the pandemic's causative agent (bacterium Yersinia pestis), our knowledge of the Black Death remains limited, based primarily on qualitative remarks in medieval written sources available for some areas of Western Europe. Here, we remedy this situation by applying a pioneering new approach, 'big data palaeoecology', which, starting from palynological data, evaluates the scale of the Black Death's mortality on a regional scale across Europe. We collected pollen data on landscape change from 261 radiocarbon-dated coring sites (lakes and wetlands) located across 19 modern-day European countries. We used two independent methods of analysis to evaluate whether the changes we see in the landscape at the time of the Black Death agree with the hypothesis that a large portion of the population, upwards of half, died within a few years in the 21 historical regions we studied. While we can confirm that the Black Death had a devastating impact in some regions, we found that it had negligible or no impact in others. These inter-regional differences in the Black Death's mortality across Europe demonstrate the significance of cultural, ecological, economic, societal and climatic factors that mediated the dissemination and impact of the disease. The complex interplay of these factors, along with the historical ecology of plague, should be a focus of future research on historical pandemics.The authors acknowledge the following funding sources: Max Planck Independent Research Group, Palaeo-Science and History Group (A.I., A.M. and C.V.); Estonian Research Council #PRG323, PUT1173 (A.Pos., T.R., N.S. and S.V.); European Research Council #FP7 263735 (A.Bro. and A.Plu.), #MSC 655659 (A.E.); Georgetown Environmental Initiative (T.N.); Latvian Council of Science #LZP-2020/2-0060 (N.S. and N.J.); LLNL-JRNL-820941 (I.T.); NSF award #GSS-1228126 (S.M.); Polish-Swiss Research Programme #013/2010 CLIMPEAT (M.Lam.), #086/2010 CLIMPOL (A.W.); Polish Ministry of Science and Higher Education #N N306 275635 (M.K.); Polish National Science Centre #2019/03/X/ST10/00849 (M.Lam.), #2015/17/B/ST10/01656 (M.Lam.), #2015/17/B/ST10/03430 (M.Sło.), #2018/31/B/ST10/02498 (M.Sło.), #N N304 319636 (A.W.); SCIEX #12.286 (K.Mar.); Spanish Ministry of Economy and Competitiveness #REDISCO-HAR2017-88035-P (J.A.L.S.); Spanish Ministry of Education, Culture and Sports #FPU16/00676 (R.L.L.); Swedish Research Council #421-2010-1570 (P.L.), #2018-01272 (F.C.L. and A.S.); Volkswagen Foundation Freigeist Fellowship Dantean Anomaly (M.B.), Spanish Ministry of Science and Innovation #RTI2018-101714-B-I00 (F.A.S. and D.A.S.), OP RDE, MEYS project #CZ.02.1.01/0.0/0.0/16_019/0000728 (P.P.

Palaeoecological data indicates land-use changes across Europe linked to spatial heterogeneity in mortality during the Black Death pandemic

Historical accounts of the mortality outcomes of the Black Death plague pandemic are variable across Europe, with much higher death tolls suggested in some areas than others. Here the authors use a 'big data palaeoecology' approach to show that land use change following the pandemic was spatially variable across Europe, confirming heterogeneous responses with empirical data.The Black Death (1347-1352 ce) is the most renowned pandemic in human history, believed by many to have killed half of Europe's population. However, despite advances in ancient DNA research that conclusively identified the pandemic's causative agent (bacterium Yersinia pestis), our knowledge of the Black Death remains limited, based primarily on qualitative remarks in medieval written sources available for some areas of Western Europe. Here, we remedy this situation by applying a pioneering new approach, 'big data palaeoecology', which, starting from palynological data, evaluates the scale of the Black Death's mortality on a regional scale across Europe. We collected pollen data on landscape change from 261 radiocarbon-dated coring sites (lakes and wetlands) located across 19 modern-day European countries. We used two independent methods of analysis to evaluate whether the changes we see in the landscape at the time of the Black Death agree with the hypothesis that a large portion of the population, upwards of half, died within a few years in the 21 historical regions we studied. While we can confirm that the Black Death had a devastating impact in some regions, we found that it had negligible or no impact in others. These inter-regional differences in the Black Death's mortality across Europe demonstrate the significance of cultural, ecological, economic, societal and climatic factors that mediated the dissemination and impact of the disease. The complex interplay of these factors, along with the historical ecology of plague, should be a focus of future research on historical pandemics

Testing the Effect of Relative Pollen Productivity on the REVEALS Model : A Validated Reconstruction of Europe-Wide Holocene Vegetation

Reliable quantitative vegetation reconstructions for Europe during the Holocene are crucial to improving our understanding of landscape dynamics, making it possible to assess the past effects of environmental variables and land-use change on ecosystems and biodiversity, and mitigating their effects in the future. We present here the most spatially extensive and temporally continuous pollen-based reconstructions of plant cover in Europe (at a spatial resolution of 1° × 1°) over the Holocene (last 11.7 ka BP) using the 'Regional Estimates of VEgetation Abundance from Large Sites' (REVEALS) model. This study has three main aims. First, to present the most accurate and reliable generation of REVEALS reconstructions across Europe so far. This has been achieved by including a larger number of pollen records compared to former analyses, in particular from the Mediterranean area. Second, to discuss methodological issues in the quantification of past land cover by using alternative datasets of relative pollen productivities (RPPs), one of the key input parameters of REVEALS, to test model sensitivity. Finally, to validate our reconstructions with the global forest change dataset. The results suggest that the RPPs.st1 (31 taxa) dataset is best suited to producing regional vegetation cover estimates for Europe. These reconstructions offer a long-term perspective providing unique possibilities to explore spatial-temporal changes in past land cover and biodiversity

Palaeoecological data indicates land-use changes across Europe linked to spatial heterogeneity in mortality during the Black Death pandemic

The Black Death (1347–1352 CE) is the most renowned pandemic in human history, believed by many to have killed half of Europe’s population. However, despite advances in ancient DNA research that conclusively identified the pandemic’s causative agent (bacterium Yersinia pestis), our knowledge of the Black Death remains limited, based primarily on qualitative remarks in medieval written sources available for some areas of Western Europe. Here, we remedy this situation by applying a pioneering new approach, ‘big data palaeoecology’, which, starting from palynological data, evaluates the scale of the Black Death’s mortality on a regional scale across Europe. We collected pollen data on landscape change from 261 radiocarbon-dated coring sites (lakes and wetlands) located across 19 modern-day European countries. We used two independent methods of analysis to evaluate whether the changes we see in the landscape at the time of the Black Death agree with the hypothesis that a large portion of the population, upwards of half, died within a few years in the 21 historical regions we studied. While we can confirm that the Black Death had a devastating impact in some regions, we found that it had negligible or no impact in others. These inter-regional differences in the Black Death’s mortality across Europe demonstrate the significance of cultural, ecological, economic, societal and climatic factors that mediated the dissemination and impact of the disease. The complex interplay of these factors, along with the historical ecology of plague, should be a focus of future research on historical pandemics.The authors acknowledge the following funding sources: Max Planck Independent Research Group, Palaeo-Science and History Group (A.I., A.M. and C.V.); Estonian Research Council #PRG323, PUT1173 (A.Pos., T.R., N.S. and S.V.); European Research Council #FP7 263735 (A.Bro. and A.Plu.), #MSC 655659 (A.E.); Georgetown Environmental Initiative (T.N.); Latvian Council of Science #LZP-2020/2-0060 (N.S. and N.J.); LLNL-JRNL-820941 (I.T.); NSF award #GSS-1228126 (S.M.); Polish-Swiss Research Programme #013/2010 CLIMPEAT (M.Lam.), #086/2010 CLIMPOL (A.W.); Polish Ministry of Science and Higher Education #N N306 275635 (M.K.); Polish National Science Centre #2019/03/X/ST10/00849 (M.Lam.), #2015/17/B/ST10/01656 (M.Lam.), #2015/17/B/ST10/03430 (M.Sło.), #2018/31/B/ST10/02498 (M.Sło.), #N N304 319636 (A.W.); SCIEX #12.286 (K.Mar.); Spanish Ministry of Economy and Competitiveness #REDISCO-HAR2017-88035-P (J.A.L.S.); Spanish Ministry of Education, Culture and Sports #FPU16/00676 (R.L.L.); Swedish Research Council #421-2010-1570 (P.L.), #2018-01272 (F.C.L. and A.S.); Volkswagen Foundation Freigeist Fellowship Dantean Anomaly (M.B.), Spanish Ministry of Science and Innovation #RTI2018-101714-B-I00 (F.A.S. and D.A.S.), OP RDE, MEYS project #CZ.02.1.01/0.0/0.0/16_019/0000728 (P.P.)Peer reviewe

Palaeoecological data indicates land-use changes across Europe linked to spatial heterogeneity in mortality during the Black Death pandemic

The Black Death (1347–1352 CE) is the most renowned pandemic in human history, believed by many to have killed half of Europe’s population. However, despite advances in ancient DNA research that conclusively identified the pandemic’s causative agent (bacterium Yersinia pestis), our knowledge of the Black Death remains limited, based primarily on qualitative remarks in medieval written sources available for some areas of Western Europe. Here, we remedy this situation by applying a pioneering new approach, ‘big data palaeoecology’, which, starting from palynological data, evaluates the scale of the Black Death’s mortality on a regional scale across Europe. We collected pollen data on landscape change from 261 radiocarbon-dated coring sites (lakes and wetlands) located across 19 modern-day European countries. We used two independent methods of analysis to evaluate whether the changes we see in the landscape at the time of the Black Death agree with the hypothesis that a large portion of the population, upwards of half, died within a few years in the 21 historical regions we studied. While we can confirm that the Black Death had a devastating impact in some regions, we found that it had negligible or no impact in others. These inter-regional differences in the Black Death’s mortality across Europe demonstrate the significance of cultural, ecological, economic, societal and climatic factors that mediated the dissemination and impact of the disease. The complex interplay of these factors, along with the historical ecology of plague, should be a focus of future research on historical pandemics

Holocene history of Taxus baccata in the Basque mountains (northern Iberian Peninsula)

Palaeobotanical studies are a very interesting tool for evaluating past vegetation, climatic variability and human pressure on the landscape. In this paper we offer an overview of Holocene evolution of the yew (Taxus baccata L.) in the Basque Mountains (Northern Iberian Peninsula). For this purpose, we have collected all macro- and micro-remain evidence of the presence of yew within its chronological framework. The results suggest the existence of a period of expansion of yew populations during the Middle Holocene and a regression phase in the Late Holocene.Los estudios paleobotánicos son una herramienta de gran interés para conocer la evolución de la cubierta vegetal del pasado, además de las condiciones climáticas y la dinámica antrópica. Pero también resulta muy útil a la hora de evaluar la historia de particular de algunas especies. En este trabajo ofrecemos una visión sintética de la evolución holocena del tejo (Taxus baccata L.) en las montañas vascas (Norte de la Península Ibérica). Para ello hemos recogido todos los depósitos con macrorestos o microrrestos botánicos de tejo, así como su adscripción cronológica. Los resultados sugieren la existencia de un período de expansión de los tejos durante el Holoceno medio, así como una fase de regresión durante el Holoceno final.This study was funded by the Consolider Research Program in Technologies for Evaluation and Preservation of Cultural Heritage-TCP-CSD2007-00058 and the HAR2011-23716 project (Plan Nacional I+D+i, Spain)