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Understanding long-term fire ecology is essential for current day interpretation of ecosystem fire responses. However palaeoecology of fire is still poorly understood, especially at high-altitude mountain environments, despite the fact that these are fire-sensitive ecosystems and their resilience might be affected by changing fire regimes. We reconstruct wildfire occurrence since the Lateglacial (14.7. cal. ka BP) to the Mid-Holocene (6. cal. ka BP) and investigate the climate-fuel-fire relationships in a sedimentary sequence located at the treeline in the Central Spanish Pyrenees. Pollen, macro- and micro-charcoal were analysed for the identification of fire events (FE) in order to detect vegetation post-fire response and to define biomass-fire interactions. mean fire intervals (mfi) reduced since the Lateglacial, peaking at 9-7.7. cal. ka BP while from 7.7 to 6. cal. ka BP no fire is recorded. We hypothesise that Early Holocene maximum summer insolation, as climate forcing, and mesophyte forest expansion, as a fuel-creating factor, were responsible for accelerating fire occurrence in the Central Pyrenees treeline. We also found that fire had long-lasting negative effects on most of the treeline plant communities and that forest contraction from 7.7. cal. ka BP is likely linked to the ecosystem's threshold response to high fire frequencies. © 2014 Elsevier B.V. ; This research has been funded by the projects DINAMO (CGL2009-07992) (funding EGPF — grant ref. BES-2010-038593 and MSC), DINAMO2 (CGL2012-33063), ARAFIRE (2012 GA LC 064), GRACCIE-CONSOLIDER (CSD2007-00067). GGR was funded by the Juan de la Cierva Program (grant ref. JCI2009-04345) and JAE-Doc CSIC Program, LLM was supported by a postdoctoral MINT fellowship funded by the Institute for the Environment (Brunel University), AMC is a Ramón y Cajal fellow (ref: RYC-2008-02431), APS holds a grant funded by the Aragon Government (ref. 17030G/5423/480072/14003) and JAE holds a grant funded by the Basque Country Government (BFI-2010-5). We are indebted to Beatriz Bueno and Aida Adsuar for sampling processing and laboratory analyses and to César Morales del Molino for productive discussions on the ideas of this paper. We are grateful to Steven M. Holland for providing the free software to calculate rarefaction (Analytic Rarefaction), which is available at http://strata.uga.edu/software/. ; Peer Reviewed

The sedimentological, geochemical and palynological analyses performed in the Conquezuela palaeolake (41°11′N; 2°33′W; 1124 m a.s.l.) provide a detailed, multiproxy palaeoenvironmental reconstruction in one of the key areas of inner Iberian Neolithic colonization. Combined with archaeobotanical and archaeological data from well-dated settlements along the Conquezuela–Ambrona Valley we investigate how environmental conditions may affect both socio-economic adaptations and livelihood strategies of prehistoric communities. The first evidences of early Neolithic occupation in the valley ca. 7250–6450 cal yr BP (5300–4500 BC) coincided with the onset of a period (7540–6200 cal yr BP, 5590–4250 BC) with higher water availability and warmer climate as alluvial environments were substituted by carbonate-wetland environments in the basin. The Conquezuela record supports an early Neolithic colonization of the inner regions of Iberia favored by warmer and humid climate features and with preferential settlement patterns associated to lakes. The maximum human occupation of the valley occurred during the mid–late Neolithic and Chalcolithic (6200–3200 cal yr BP, 4250–1250 BC) as evidenced by the high number of archaeological sites. Although a number of hydrological oscillations have been detected during this period, the intense landscape transformation at basin-scale, leading to a deforested landscape, was largely a consequence of widespread farming and pastoral practices. Socio-economic activities during Bronze, Iron and Roman times modified this inherited landscape, but the second largest ecosystem transformation only occurred during Mediaeval times when a new agrarian landscape developed with the expansion of stockbreeding transhumance. The current vegetation cover characterized by patches of holm and marcescent oaks and fields reflects an intense human management combining both extensive herding with agrarian activities in order to transform the previous forested landscape into a dehesa-like system. ; The funding for the present study derives from DINAMO2 (CGL-BOS 2012-33063) and AGRIWESTMED (ERC Grant Agreement #230561) projects, provided by the Spanish Inter-Ministry Commission of Science and Technology (CICYT) and the European Research Council under the European Union's Seventh Framework Programme (FP7/2007–2013). XRF data were obtained at the XRF Core Scanner Laboratory (CRG Marine Geosciences, University of Barcelona). Josu Aranbarri acknowledges the predoctoral funding provided by the Basque Country Government (ref: FI-2010-5). Graciela Gil-Romera hold a post-doctoral contract funded by "Juan de la Cierva" (ref: JCI2009-04345) program. Eduardo García-Prieto and Maria Leunda are supported by predoctoral FPI grants BES-2010-038593 and BES-2013-063753, respectively. We also thank Elena Royo for her help with the lab procedures and the two anonymous referees for their valuable suggestions. ; Peer reviewed

Palynological, sedimentological and geochemical analyses performed on the Villarquemado paleolake sequence (987 m a.s.l, 40°30′N; 1°18′W) reveal the vegetation dynamics and climate variability in continental Iberia over the last 13,500 cal yr BP. The Lateglacial and early Holocene periods are characterized by arid conditions with a stable landscape dominated by pinewoods and steppe until ca. 7780 cal yr BP, despite sedimentological evidence for large paleohydrological fluctuations in the paleolake. The most humid phase occurred between ca. 7780 and 5000 cal yr BP and was characterized by the maximum spread of mesophytes (e.g., Betula, Corylus, Quercus faginea type), the expansion of a mixed Mediterranean oak woodland with evergreen Quercus as dominant forest communities and more frequent higher lake level periods. The return of a dense pinewood synchronous with the depletion of mesophytes characterizes the mid-late Holocene transition (ca. 5000 cal yr BP) most likely as a consequence of an increasing aridity that coincides with the reappearance of a shallow, carbonate wetland environment. The paleohydrological and vegetation evolution shows similarities with other continental Mediterranean areas of Iberia and demonstrates a marked resilience of terrestrial vegetation and gradual responses to millennial-scale climate fluctuations. Human impact is negligible until the Ibero-Roman period (ca. 2500 cal yr BP) when a major deforestation occurred in the nearby pine forest. The last 1500 years are characterized by increasing landscape management, mainly associated with grazing practices shaping the current landscape. ; The funding for the present study derives from DINAMO (CGL-BOS 2009–07992), DINAMO2 (CGL-BOS 2012–33063), IBERIAN PALEOFLORA (CGL-BOS 2012–31717) and GRACCIE-CONSOLIDER (CSD2007-00067) projects, provided by the Spanish Inter-Ministry Commission of Science and Technology (CICYT). Josu Aranbarri acknowledges the predoctoral funding provided by the Basque Country Government (ref: FI-2010-5). Ana Moreno, Graciela Gil-Romera and Mario Morellón hold post-doctoral contracts funded by "Ramon y Cajal (ref: RYC-2008-02431)", "Juan de la Cierva (ref: JCI2009-04345)" and "JAE DOC CSIC (ref: JAEDOC-2011-026)" programms, respectively. Eduardo García-Prieto is supported by a predoctoral FPI grant (BES-2010-038593). We are very greateful to Aida Adsuar, Beatriz Bueno and Raquel López-Cantero for their assistance in core sampling and laboratory procedures. Josu Aranbarri thanks collegues from the Dipartimento di Biologia Ambientale, especially Alessandra Celant, for continuous encouragement. We would also like to thank Thomas M. Cronin, Anthony C. Stevenson and an anonymous reviewer for their valuable suggestions. ; Peer reviewed

[EN] High resolution multiproxy data (pollen, sedimentology, geochemistry, chironomids and charcoal) from the Basa de la Mora (BSM) lake sequence (42°32' N, 0°19' E, 1914m a.s.l.) show marked climate variability in the central southern Pyrenees throughout the Holocene. A robust age model based on 15 AMS radiocarbon dates underpins the first precise reconstruction of rapid climate changes during the Holocene from this area. During the Early Holocene, increased winter snowpack and high snowmelt during summer, as a consequence of high seasonality, led to higher lake levels, a chironomid community dominated by non-lacustrine taxa (Orthocladiinae) related to higher inlet streams, and a forested landscape with intense run-off processes in the watershed. From 9.8 to 8.1calkaBP, climate instability is inferred from rapid and intense forest shifts and high fluctuation in surface run-off. Shifts among conifers and mesophytes reveal at least four short-lived dry events at 9.7, 9.3, 8.8 and 8.3calkaBP. Between 8.1 and 5.7calkaBP a stable climate with higher precipitation favoured highest lake levels and forest expansion, with spread of mesophytes, withdrawal of conifers and intensification of fires, coinciding with the Holocene Climate Optimum. At 5.7calkaBP a major change leading to drier conditions contributed to a regional decline in mesophytes, expansion of pines and junipers, and a significant lake level drop. Despite drier conditions, fire activity dropped as consequence of biomass reduction. Two arid intervals occurred between 2.9 and 2.4calkaBP and at 1.2-0.7calkaBP (800-1300 AD). The latter coincides with the Medieval Climate Anomaly and is one of the most arid phases of the Holocene in BSM sequence. Anthropogenic disturbances were small until 700 AD, when human pressure over landscape intensified, with Olea cultivation in the lowlands and significant deforestation in highlands. Colder and unfavourable weather conditions during the second part of the Little Ice Age caused a temporary cease of high-land management. The most intense anthropogenic disturbances occurred during the second half of 19th century. Last decades are characterized by recovery of the vegetation cover as a result of land abandonment, and lowered lake levels, probably due to higher temperatures. © 2013 Elsevier Ltd. ; Financial support for research was provided by the former Spanish Inter-Ministry Commission of Science and Technology (CICIYT) through the projects DINAMO (CGL2009-07992), DINAMO2 (CGL2012-33063), GRACCIE-CONSOLIDER (CSD2007-00067) and HORDA (83/2008), from Parques Nacionales. Additional funding support has been provided by the Aragon Government through the project PM073/2007 and by Geoparque del Sobrarbe through the project "High resolution chronological control of Basa de la Mora". Ana Pérez-Sanz has been supported by a PhD Fellowship provided by the Aragon Government. Ana Moreno, Graciela Gil-Romera and Mario Morellón hold post-doctoral contracts funded by the "Ramón y Cajal", "Juan de la Cierva" and "JAE-DOC CSIC" programs, respectively. We thank to Santiago Giralt, Alberto Sáez, Armand Hernández, Carlos Martí, Mayte Rico, Juan Pablo Corella and Antonio Vallejo for coring assistance in 2008. We also thank Beatriz Bueno and Aída Adsuar for their help in lab procedures. We are indebted to Prof. Sandy Harrison for her assistance with the English review that has led to a noticeable improvement of the manuscript. ; Peer Reviewed

11 Pags.- 6 Figs.- 4 Tabls. © 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license. ; Despite the exponential increase in human population at global scale, some rural areas have experienced a progressive abandonment over the last decades. Under particular socioecological and policy contexts, changes in demography may promote land-use changes and, consequently, alter ecosystem services (ES) supply. However, most studies on this topic have targeted urban population increase, whereas depopulation has been rarely addressed. Here, we examined how shifts in demographic variables (human population, population density, and number of villages) affect provisioning (water supply, food and biomass production) and regulating (soil retention, water and nutrient regulation) ES in Mediterranean rural areas with contrasting environmental, socioeconomic and land-use contexts. When depopulation results in underuse of socio-ecological systems, we expected a decrease of provisioning and an increase of regulating ES, whereas we expected the opposite pattern when it results in land-use intensification. To test this hypothesis, we compared demographic data and ES estimated with Soil and Water Assessment Tool (SWAT) linked to land-use changes between the 1950s and 2000s in three rural areas of Aragón (NE Spain). Generalized Additive Mixed Models and Linear Mixed-Effect Models were used to analyze demographic trends, ES changes and the relationship between them. We found severe depopulation (−42% inhabitants) and associated land-use changes in the three areas, which was particularly evident in isolated mountainous zones (−63% inhabitants). Depopulation trends significantly affected land use and, consequently, all of the ES evaluated. In mountainous depopulated areas, land abandonment and rewilding resulted in the increase in water regulation (>1000%) and soil retention (>400%). In contrast, agriculture was intensified in more fertile and easy-to-access lowland areas, boosting the food production service (>600%). Accordingly, the interactions among depopulation, crop production and regulating ES should be considered in the management schemes and policies targeting rural areas for a balanced and sustainable supply of ES in the long term. ; This study, which is part of the Ecological Restoration Research Group (E40-17R) work, was funded by Aragón Government, Dpt. Innovation, Research and University and the European Regional Development Fund. DB was funded by "PTI ECOBIODIV" through the "Vicepresidencia Adjunta de Áreas Científico-Técnicas (VAACT-CSIC) and "Juan de la Cierva" research contract (Spanish MINECO FJCI-2016-29856) at Instituto Pirenaico de Ecología (IPE-CSIC, Spain). CC was supported by the Spanish Ministry of Education, Culture and Sport under FPU contract (FPU14/01682). BG was supported by a research fellowship funded by the Spanish Program of R+D+I (RyC2018-025160-I). JJJ acknowledges the support of ARAID foundation. FP was funded by "Consejería de Transformación Económica, Industria, Conocimiento y Universidad-Fondo Social Europeo de Andalucía 2014-2020". Finally, we thank the AMUSE project funded by Spanish Ministry of Economy and Competitiveness (Research Challenge projects: CGL2014-53017 C2-1-R) for ecological data. ; Peer reviewed