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21 páginas, 12 figuras, 2 tablas. ; [EN]: Four distinctive depositional subenvironments of fossil travertines and stromatolites are identified in three high-altitude (3500–4000 m above sea level) lacustrine basins: El Peinado, San Francisco (Las Coladas Salar subbasin), and Las Peladas (southern Andean Altiplano, northwestern Argentina). These late Quaternary occurrences are characterized using geomorphological, sedimentological, petrographic, and stable isotopic data. Stromatolites of cyanobacterial origin only develop in shallow lacustrine margins of El Peinado basin. In the same basin, macrophytic travertines occur both near thermal spring seepage areas along the lake margin as in situ facies and in littoral lacustrine environments up to water depths of several metres as phytoclastic travertine facies. The stromatolites and macrophytic travertines have relatively heavy δ18O compositions, suggesting initial 16O-depleted waters and (or) evaporation effects through time. Their high δ13C compositions are interpreted as a reflection of intense CO2 evasion from the thermal groundwaters feeding the lakes. Similar laminated travertine facies, with no petrographic evidence for biotic origin, occur in both Las Coladas and Las Peladas basins. Neither petrographic nor isotopic data alone can differentiate between these two cases. Besides, diagenetic overprint in Las Peladas facies precludes the use of isotopic values as original isotopic signatures. However, the depositional environmental conditions defined by the geomorphological and sedimentological features are different. Laminated aragonitic crusts in Las Coladas basin formed in a shallow, saline lake and are associated with shoreline and terrace deposits cemented by aragonite. These travertine crusts represent periods of spring, 16O-rich discharge to the lake, as suggested by the lighter oxygen isotopic compositions. In contrast, travertines from Las Peladas occur as laminated calcitic and aragonitic units intercalated at the top of fining-upward sequences composed of conglomerates, sandstones, and intraclastic limestones. Sedimentological data suggest that these travertines originated in fluvial-influenced lake margins during low lake-level episodes. ; [FR]: Quatre sous-environnements distincts de déposition de 1tr2a8v3ertins et de stromatolithes fossilifères sont identifiés dans trois bassins lacustres de haute altitude (3500–4000 mètres au-dessus du niveau de la mer), soit les bassins El Peinado, Lad Coladas et Las Peladas (Altiplano andain sud, au nord-ouest de l'Argentine). Ces occurrences du Quaternaire tardif sont caractérisées au moyen de données géomorphologiques, sédimentologiques, pétrographiques et d'isotopes stables. Les stromatolithes d'origine cyanobactérienne ne se développent que dans les marges lacustres peu profondes du bassin El Peinado. Dans ce même bassin, les travertins macrophytiques se retrouvent près de régions de sources d'infiltration thermales le long de la bordure du lac, en tant que faciès in situ, et dans des environnements lacustres littoraux jusqu'à des profondeurs de plusieurs mètres, en tant que faciès de travertins phytoclastiques. Les stromatolithes et les travertins macrophytiques ont des compositions relativement élevées en δ18O, suggérant des eaux initialement pauvres en 16O et (ou) des effets de l'évaporation dans le temps. Leurs compositions élevées en δ13C sont interprétées comme le reflet d'un échappement intense de CO2 des eaux souterraines thermales qui alimentent les lacs. Des faciès semblables de travertins laminés, sans évidence pétrographique d'une origine biotique, se retrouvent dans les bassins de Las Coladas et de Las Peladas. Ni les données pétrographiques ni les données isotopiques ne peuvent seules faire la différence entre ces deux cas. De plus, la surimpression diagénétique dans le faciès Las Peladas empêche l'utilisation de valeurs isotopiques en tant que signatures isotopiques d'origine. Toutefois, les conditions environnementales de déposition définies par les caractéristiques géomorphologiques et sédimentologiques sont différentes. Des croûtes laminées d'aragonite dans le bassin de Las Coladas forment un lac salé peu profond et elles sont associées aux dépôts de rivage et de terrasse cimentés par l'aragonite. Ces croûtes de travertin représentent les périodes de printemps, de décharge riche en 16O vers le lac, tel que suggéré par les compositions isotopiques d'oxygène plus léger. Par contre, les travertins de Las Peladas se présentent comme des unités calcitiques et aragonitiques laminées intercalées au sommet de séquences à affinement vertical ascendant composées de conglomérats, de grès et de calcaires intraclastiques. Les données sédimentologiques suggèrent que ces travertins proviennent de bordures des lacs influencés par les cours d'eau au cours d'épisodes où le niveau du lac est bas. ; Financial support for fieldwork was provided by the Universidad Nacional de Catamarca, Argentina, and by the Departamento de Relaciones Internacionales (Consejo Superior de Investigaciones Científicas, Spain). This investigation was also funded by project PB97-0882-C03-02 of the Spanish government. ; Peer reviewed

AbstractOwing to increasing anthropogenic impacts, wetlands have suffered a serious environmental decline in recent decades. The sustainable management of these natural resources is fundamental to maintain both the ecosystems and the economic activities. The Lake Massaciuccoli and nearby areas represent one of the largest residual coastal marshy areas in Tuscany (Italy). This wetland is characterized by large-scale and intensive agricultural use and affected by reclamation activities, with consequent problems of erosion, subsidence and lake eutrophication and siltation. In this context, an integrated study combining hydrochemical data (water levels, electrical conductivity, pH, turbidity, major ions, trace metals) and stable isotopes (H, O, S) has been performed in the southernmost part of the basin, to better disentangle processes and interactions between groundwater and surface water and to understand the origin of solutes and their evolution. Our results indicated that both groundwater and surface water have a meteoric origin and that geochemical composition of groundwater is mainly affected by local geological and biological processes. Moreover, surface water is affected by sea water mixing and evapotranspiration/precipitation processes. The impact of agricultural activity and the use of fertilizers on the water quality appears to be limited as regards nitrates, indicating that less intense agricultural practices implemented in recent years have been successful. As regards sulfates, Fe, and Mn, we cannot fully elucidate the mechanisms underlying human influence, but the oscillation of water level and degradation of peat enhanced by reclamation and agriculture activities likely played an important role in controlling the fate of these elements. Overall, these results underline the importance of integrated approaches to disentangle geochemical processes and will be useful in supporting policy implementation and environmental protection in this valuable area of Tuscany. Findings from this work suggest the need for policy-making authorities to take actions as soon as possible to mitigate risks. Closer co-operation is essential between authorities and farmers to reduce inputs of fertilizers and chemicals into the lake and the surrounding area. Also, additional policy measures should be enforced to reduce the mechanical soil tillage and limit erosion and runoff, such as the NBSs implemented within the Phusicos Project.

Migrant populations must cope not only with environmental changes in different biomes, but also with the continuous constraints imposed by human-induced changes through landscape transformation and resource patchiness. Theoretical studies suggest that changes in food distribution can promote changes in the social arrangement of individuals without apparent adaptive value. Empirical research on this subject has only been performed at reduced geographical scales and/or for single species. However, the relative contribution of food patchiness and predictability, both in space and time, to abundance and sociality can vary among species, depending on their degree of flexibility. ; This work was supported by the project CGL2004-00270 of Spanish Government. ; Peer reviewed

[EN] A one-year monitoring survey has been carried out in La Paz and La Viña Caves in the Ortigosa de Cameros Cave System (NE Iberian Peninsula), in order to track the oxygen isotope signal from rainfall to speleothem calcite, assessing the ability of this signal to retain environmental information. Oxygen isotope signals of rainfall events, drip water —sampled every three months—, and speleothem calcite, precipitated over three-months, are compared. Water dripping follows precipitation events in winter, spring and summer, more closely in the near-surface drip points than in the deeper ones. In autumn, dripping is delayed with respect to rainfall, suggesting that water stays in the epikarst before dripping resumes after summer. This delay causes a deviation of the total drip water signal (average δ18O=−8.39‰ V-SMOW) from the rainfall signal (average δ18O=−7.41‰ V-SMOW). On the contrary, in winter the isotopic signal of drip water keeps the rainfall signal. Calcite isotopic signal (total average δ18O=−6.83‰ V-PDB) shows a small offset (0.62–0.75%) with respect to the signal predicted by drip water oxygen composition; this points to a limited kinetic effect in calcite precipitation, therefore calcite retains the signal of rainfall, especially in winter. ; [ES] Durante un año se han monitorizado las cuevas de La Paz y La Viña en el Sistema de Cuevas de Ortigosa de Cameros (NE de la Península Ibérica) para rastrear la señal isotópica del oxígeno desde la lluvia a la calcita espeleotémica, y así valorar la capacidad de esta señal para conservar información medioambiental. Se han comparado las señales isotópicas del oxígeno de los eventos de la lluvia, el agua de goteo (muestreada trimestralmente) y la calcita espeleotémica, precipitada también durante cada trimestre. El goteo en las cuevas responde a la precipitación en invierno, primavera y verano, más estrechamente en los puntos más próximos a la superficie que en los profundos. En otoño hay un retraso entre la lluvia y el goteo, lo que sugiere que el agua permanece por un tiempo en el epikarst, antes de que se reanude el goteo después del verano. Este retraso provoca que la señal isotópica del agua de goteo (media total de δ18O=−8.39‰ V-SMOW) se desvíe de la señal de la lluvia (media de δ18O=−7,41‰ V-SMOW). Por el contrario, en invierno la señal isotópica del agua de goteo es muy semejante a la de la lluvia. La composición isotópica de la calcita espeleotémica (media total de δ18O=−6,83‰ V-PDB) presenta un pequeño desfase (0,62–0,75%) respecto al valor que le correspondería por la composición isotópica del agua de goteo; esto indica que los efectos cinéticos durante la precipitación de la calcita son limitados, por lo que ésta conserva la señal de la lluvia, especialmente en invierno. ; This study was mainly funded by the CGL2009-10455/BTE research project of the Ministry of Science and Innovation and FEDER and the Análisis de Cuencas Sedimentarias Continentales, Geotransfer, PaleoQ y Gemorfología y Cambio Global research groups of the Aragón Government. We are most grateful to Ma Angeles, Sara y Juan for their invaluable help. We also thank to the Ortigosa de Cameros town hall for the cave access. The Government of La Rioja is acknowledged by the meteorological data from Villoslada de Cameros station. We are indebted to the referees for their valuable comments. ; Peer reviewed

The final version is available at: http://www.sciencedirect.com/science/journal/00310182 ; Although the Central Ebro Basin (Northeastern Iberian Peninsula) is both the northernmost semi-arid area in Europe and one of the regions with the largest biodiversity, it has been insufficiently studied in terms of past climate variability due to the scarcity of suitable sites for palaeoenvironmental analyses. Previous studies from ephemeral saline lakes in the area, mainly based on palynological data, show abrupt and rapid arid/humid transitions throughout the last glacial cycle highlighting a complex palaeohydrological evolution. New cores from two saline lakes (La Playa and La Salineta) in the Los Monegros area provide multi-proxy records including sedimentology, geochemistry, and pollen indicators. This study, together with a detailed and comprehensive review of the main saline records from the Central Ebro Basin, enables us tos reconstruct a comprehensive picture of the palaeoclimate evolution during the last glacial cycle. One of the main results of this study is the alternation of humid and dry phases as a characteristic of the climate evolution during the Lateglacial. Additionally, the study suggests an important role of the increased flow from the Pyrenean rivers during deglaciation in the hydrological balance of the Central Ebro Basin. It is found that the Early Holocene is the wettest period over the sequence studied contrasting with the arid Middle Holocene interval, which is frequently absent as a result of intense aeolian erosive processes. Although anthropogenic activity partially masks the climate signal from the palynological data in the uppermost part of the sequences studied, there are some sedimentological evidences for a climate change during the last 2000 years resulting in a recovery of average saline lake levels in the Central Ebro Basin. ; This work was part of the project "Arid periods in the Mediterranean area since the Last Glacial Maximum" (REN 2000-1136/CLI), and LIMNOCLIBER (REN 2003-09130-C02-02), funded by the CICYT, and the project "Environmental evolution and effects of the anthropogenic impact in the lacustrine complex of Bujaraloz–Sástago" (PO23/2001), funded by the Aragon regional government (DGA). We acknowledge the Pyrenean Institute of Ecology (CSIC) for financial support. ; Peer reviewed

30 páginas, 6 figuras ; Combined sedimentary facies, geochemical analyses and pollen spectra from lake records and sedimentological and palynological studies from slope deposits allow the characterization of vegetation and lake level status during glacial times in the central Ebro valley (NE Spain). These records show the presence of some increased effective moisture periods while regional vegetation was dominated by steppe taxa. The longest lake record comes from La Salineta, one of the saline lake in the Los Monegros area; the other lake sequence comes from a sinkhole in the Gállego river floodplain. The slope deposit from Valmadrid is the only periglacial deposit found in the central Ebro valley. Our data indicate that - at least for some intervals during full glacial times – when cold steppe vegetation dominated the region, some lakes experienced more positive water balance than today and run-off was also high. The data are coherent with the hypothesis that – at least for some periods- the ice-age climate of the western Mediterranean was characterized by cold winters, relative intense winter precipitation and summer droughts. Increased flow from the Pyrenean rivers during the early deglaciation could also play a significant role in the paleohydrological conditions in the central Ebro valley. However, La Salineta records also show the occurrence of arid periods during glacial times, indicating a complex picture of hydrological and moisture evolution in the central Ebro valley during the LGM. ; The research in the central Ebro valley was funded by the Aragonese Regional Government (Project PO23/2001: "Environmental evolution and human impact in the Bujaraloz-Sástago lake complex. Scientific bases for conservation and sustainable development of the Los Monegros saline lakes"), and the Spanish Government (CICYT Project REN2000 "Arid Periods in the Mediterranean areas of the Iberian Peninsula since the Last Glacial maximum: Chronology, characterization and paleoclimate implications" ). ; Peer reviewed

Recent studies have proved that high elevation environments, especially remote wetlands, are exceptional ecological sensors of global change. For example, European glaciers have retreated during the 20th century while the Sierra Nevada National Park in southern Spain witnessed the first complete disappearance of modern glaciers in Europe. Given that the effects of climatic fluctuations on local ecosystems are complex in these sensitive alpine areas, it is crucial to identify their long-term natural trends, ecological thresholds, and responses to human impact. In this study, the geochemical records from two adjacent alpine bogs in the protected Sierra Nevada National Park reveal different sensitivities and long-term environmental responses, despite similar natural forcings, such as solar radiation and the North Atlantic Oscillation, during the late Holocene. After the Industrial Revolution both bogs registered an independent, abrupt and enhanced response to the anthropogenic forcing, at the same time that the last glaciers disappeared. The different response recorded at each site suggests that the National Park and land managers of similar regions need to consider landscape and environmental evolution in addition to changing climate to fully understand implications of climate and human influence. © 2017 The Author(s). ; This study was supported by the project P11-RNM 7332 of the "Junta de Andalucía", the projects CGL2013-47038-R and CGL2015-67130-C2-1-R of the "Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER" and the research group RNM0190 and RNM309 (Junta de Andalucía). A.G.-A. was also supported by a Marie Curie Intra-European Fellowship of the 7th Framework Programme for Research, Technological Development and Demonstration of the European Commission (NAOSIPUK. Grant Number: PIEF-GA-2012-623027) and by a Ramón y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de Economía y Competividad). J.L.T. was also supported by a Small Research Grant by the Carnegie Trust for the Universities of Scotland and hosted the NAOSIPUK project (PIEF-GA-2012-623027). M. J. R-R acknowledges the PhD funding provided by Consejería de Economía, Innovación, Ciencia y Empleo de la Junta de Andalucía (P11-RNM 7332). We would like to thank to Dr. I.M. Sánchez Almazo (CIC- University of Granada), A. Cochrane, J. McGourlay, S. Pauchet (University of Glasgow), and Dr. S. Diez (IDAEA-CSIC) for their help preparing and analysing the organic and inorganic samples, as well as to Dr. I. Reche (University of Granada) for the aerosol samples from Sierra Nevada. Authors would also like to thank the journal editor K.H. Knorr and two anonymous reviewers for their comments improving the manuscript. ; Peer reviewed

40 Pag., 2 Tabl., 6 Fig. The definitive version is available at: http://www.sciencedirect.com/science/journal/00335894 ; Palynological, sedimentological and stable isotopic analyses of carbonates and organic matter performed on the El Portalet sequence (1802 m a.s.l., 42°48′00N, 0°23′52W) reflect the paleoclimatic evolution and vegetation history in the central-western Spanish Pyrenees over the last 30,000 yr, and provide a high-resolution record for the late glacial period. Our results confirm previous observations that deglaciation occurred earlier in the Pyrenees than in northern European and Alpine sites and point to a glacial readvance from 22,500 to 18,000 cal yr BP, coinciding with the global last glacial maximum. The patterns shown by the new, high-resolution pollen data from this continental sequence, chronologically constrained by 13 AMS 14C dates, seem to correlate with the rapid climate changes recorded in Greenland ice cores during the last glacial–interglacial transition. Abrupt events observed in northern latitudes (Heinrich events 3 to 1, Oldest and Older Dryas stades, Intra-Allerød Cold Period, and 8200 cal yr BP event) were also identified for the first time in a lacustrine sequence from the central-western Pyrenees as cold and arid periods. The coherent response of the vegetation and the lake system to abrupt climate changes implies an efficient translation of climate variability from the North Atlantic to mid latitudes. ; This study was partially funded by projects REN 2000-1136/CLI, REN2003-02499-GLO and REN-2003-09130-CO202, by the CICYT and PI-17/00739/FS/01 (Fundación Séneca). Funding for P.G.S. was provided by the Spanish Government (post-doctoral grant in UPS-Toulouse, France). ; Peer reviewed

Measurements of isotopic composition of marine primary producers are a valuable tool to follow and trace the source and cycling of organic matter in the marine systems, as well to describe the physiological status of aquatic photosynthetic organisms. Although stable isotope data abounds in the literature, relatively limited information regarding the isotopic signatures of marine primary producers is available for the Red Sea. Here we present data on carbon concentration (and nitrogen when possible) of phytoplankton, macroalgae, seagrasses, mangroves and salt-marsh plants, and examine how their isotopic signatures differed among plant types across a north-south gradient in the Red Sea. We also tested the potential use of deuterium, δD, to distinguish among primary producers whose carbon isotopic values may overlap. Our findings showed a clear differentiation of carbon and nitrogen content between the different groups of primary producers, as well as between species. Seagrasses and mangroves had on average larger carbon (30 and 49% of C, respectively) and nitrogen content (1.8% N) than other groups. In terms of stable carbon isotopes, seagrasses, and macroalgae tended to be heavier (−7.3 and −13.3%0, respectively) than halophytes, mangroves, and phytoplankton, which showed statistically similar and lighter δ13C values (between −24 and −26%0). There was a tendency for the nitrogen isotopic composition of seagrass and macroalgae to become lighter from the southern to the northern Red Sea, in parallel to a decline in nitrogen concentration in the tissues, indicative of a higher dependence of nitrogen fixation as a source of nitrogen toward the more oligotrophic northern Red Sea. Our results showed an overlap in the δ13C and δ15N values between macroalgae and seagrasses; however, their δD values were significantly different (seagrasses −56.6 ± 2.8%0 and macroalgae −95.7 ± 3.4%0). This remarkable difference offers a promising alternative for ecological studies where a similar range of isotopic values could mask different potential sources. ; This research was funded by King Abdullah University of Science and Technology through base-line funding to CD and SA, with references BAS/1/1071-01-01 and BAS/1/1072-01-01, and CCF funding to CD. IH was supported by a Ramon y Cajal Fellowship RYC2014-14970, cofounded by the Conselleria d'Innovació, Recerca i Turisme of the Balearic Government (Pla de ciència, tecnologia, innovació i emprenedoria 2013-2017) and the Spanish Ministry of Economy, Industry, and Competitiveness.

Measurements of isotopic composition of marine primary producers are a valuable tool to follow and trace the source and cycling of organic matter in the marine systems, as well to describe the physiological status of aquatic photosynthetic organisms. Although stable isotope data abounds in the literature, relatively limited information regarding the isotopic signatures of marine primary producers is available for the Red Sea. Here we present data on carbon concentration (and nitrogen when possible) of phytoplankton, macroalgae, seagrasses, mangroves and salt-marsh plants, and examine how their isotopic signatures differed among plant types across a north-south gradient in the Red Sea. We also tested the potential use of deuterium, δD, to distinguish among primary producers whose carbon isotopic values may overlap. Our findings showed a clear differentiation of carbon and nitrogen content between the different groups of primary producers, as well as between species. Seagrasses and mangroves had on average larger carbon (30 and 49% of C, respectively) and nitrogen content (1.8% N) than other groups. In terms of stable carbon isotopes, seagrasses, and macroalgae tended to be heavier (-7.3 and -13.3%0, respectively) than halophytes, mangroves, and phytoplankton, which showed statistically similar and lighter δC values (between -24 and -26%0). There was a tendency for the nitrogen isotopic composition of seagrass and macroalgae to become lighter from the southern to the northern Red Sea, in parallel to a decline in nitrogen concentration in the tissues, indicative of a higher dependence of nitrogen fixation as a source of nitrogen toward the more oligotrophic northern Red Sea. Our results showed an overlap in the δC and δN values between macroalgae and seagrasses; however, their δD values were significantly different (seagrasses -56.6 ± 2.8%0 and macroalgae -95.7 ± 3.4%0). This remarkable difference offers a promising alternative for ecological studies where a similar range of isotopic values could mask different potential sources. ; This research was funded by King Abdullah University of Science and Technology through base-line funding to CD and SA, with references BAS/1/1071-01-01 and BAS/1/1072-01-01, and CCF funding to CD. IH was supported by a Ramon y Cajal Fellowship RYC2014-14970, cofounded by the Conselleria d'Innovació, Recerca i Turisme of the Balearic Government (Pla de ciència, tecnologia, innovació i emprenedoria 20132017) and the Spanish Ministry of Economy, Industry, and Competitiveness.

Here we provide the geochemical dataset that our research group has collected after 10 years of investigation in the Sierra Nevada National Park in southern Spain. These data come from Holocene sedimentary records from four alpine sites (ranging from ∼2500 to ∼3000 masl): two peatlands and two shallow lakes. Different kinds of organic and inorganic analyses have been conducted. The organic matter in the bulk sediment was characterised using elemental measurements and isotope-ratio mass spectrometry (EA-IRMS). Leaf waxes in the sediment were investigated by means of chromatography with flame-ionization detection and mass spectrometry (GC-FID, GC-MS). Major, minor and trace elements of the sediments were analysed with atomic absorption (AAS), inductively coupled plasma mass spectrometry (ICP-MS), as well as X-ray scanning fluorescence. These data can be reused by environmental researchers and soil and land managers of the Sierra Nevada National Park and similar regions to identify the effect of natural climate change, overprinted by human impact, as well as to project new management policies in similar protected areas. © The Author(s) 2018. ; This study was supported by the project P11-RNM-7332 of the "Junta de Andalucía", the projects CGL2013-47038- R of the "Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER" and the research group RNM0190 and RNM309 (Junta de Andalucía). A.G.-A. was also supported by a Marie Curie Intra-European Fellowship of the 7th Framework Programme for Research, Technological Development and Demonstration of the European Commission (NAOSIPUK. Grant Number: PIEF-GA-2012-623027) and by a Ramón y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de Economía y Competividad). J.L.T. was also supported by a Small Research Grant by the Carnegie Trust for the Universities of Scotland and hosted the NAOSIPUK project (PIEF-GA-2012-623027). M.J.R-R acknowledges the PhD funding provided by Consejería de Economía, Innovación, Ciencia y Empleo de la Junta de Andalucía (P11-RNM 7332). J.C. acknowledges the PhD funding provided by "Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER". ; Peer reviewed

Recent studies have proved that high elevation environments, especially remote wetlands, are exceptional ecological sensors of global change. For example, European glaciers have retreated during the 20th century while the Sierra Nevada National Park in southern Spain witnessed the first complete disappearance of modern glaciers in Europe. Given that the effects of climatic fluctuations on local ecosystems are complex in these sensitive alpine areas, it is crucial to identify their long-term natural trends, ecological thresholds, and responses to human impact. In this study, the geochemical records from two adjacent alpine bogs in the protected Sierra Nevada National Park reveal different sensitivities and long-term environmental responses, despite similar natural forcings, such as solar radiation and the North Atlantic Oscillation, during the late Holocene. After the Industrial Revolution both bogs registered an independent, abrupt and enhanced response to the anthropogenic forcing, at the same time that the last glaciers disappeared. The different response recorded at each site suggests that the National Park and land managers of similar regions need to consider landscape and environmental evolution in addition to changing climate to fully understand implications of climate and human influence. ; This study was supported by the project P11-RNM 7332 of the "Junta de Andalucía", the projects CGL2013-47038-R and CGL2015-67130-C2-1-R of the "Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional FEDER" and the research group RNM0190 and RNM309 (Junta de Andalucía). A.G.-A. was also supported by a Marie Curie Intra-European Fellowship of the 7th Framework Programme for Research, Technological Development and Demonstration of the European Commission (NAOSIPUK. Grant Number: PIEF-GA-2012-623027) and by a Ramón y Cajal Fellowship RYC-2015-18966 of the Spanish Government (Ministerio de Economía y Competividad). J.L.T. was also supported by a Small Research Grant by the Carnegie Trust for the Universities of Scotland and hosted the NAOSIPUK project (PIEF-GA-2012-623027). M. J. R-R acknowledges the PhD funding provided by Consejería de Economía, Innovación, Ciencia y Empleo de la Junta de Andalucía (P11-RNM 7332).

18 páginas, 7 figuras, 5 tablas.-- El PDF es la versión post-print del artículo. ; The multi-proxy analysis of sediment cores recovered in karstic Lake Estanya (42°02′ N, 0°32′ E; 670 m a. s. l., NE Spain), located in the transitional area between the humid Pyrenees and the semi-arid Central Ebro Basin, provides the first high-resolution, continuous sedimentary record in the region, extending back the last 21 000 years. The integration of sedimentary facies, elemental and isotopical geochemistry and biogenic silica, together with a robust age model based on 17 AMS radiocarbon dates, enables precise reconstruction of the main hydrological and environmental changes in the region during the last deglaciation. Arid conditions, represented by shallow lake levels, predominantly saline waters and reduced organic productivity occurred throughout the last glacial maximum (21–18 cal kyrs BP) and the lateglacial, reaching their maximum intensity during the period 18–14.5 cal kyrs BP (including Heinrich event 1) and the Younger Dryas (12.9–11.6 cal kyrs BP). Less saline conditions characterized the 14.5–12.6 cal kyrs BP period, suggesting higher effective moisture during the Bölling/Allerød. The onset of more humid conditions started at 9.4 cal kyrs, indicating a delayed hydrological response to the onset of the Holocene which is also documented in several sites of the Mediterranean Basin. Higher, although fluctuating, Holocene lake levels were punctuated by a mid Holocene arid period between 4.8 and 4.0 cal kyrs BP. A major lake-level rise occurred at 1.2 cal kyrs BP, conducive to the establishment of conditions similar to the present and interrupted by a last major water level drop, occurring around 800 cal yrs BP, which coincides with the Medieval Climate Anomaly. The main hydrological stages in Lake Estanya are in phase with most Western Mediterranean and North Atlantic continental and marine records, but our results also show similarities with other Iberian and northern African reconstructions, emphasizing peculiarities of palaeohydrological evolution of the Iberian Peninsula during the last deglaciation. ; This research has been funded through the projects LIMNOCLIBER (REN2003-09130-C02-02), IBERLIMNO (CGL2005-20236-E/ CLI), LIMNOCAL (CGL2006-13327-C04-01), PALEODIVERSITAS (CGL2006-02956/BOS), GRACCIE (CSD2007-00067); provided by the Spanish Inter-Ministry Commission of Science and Technology (CICYT); and PIRINEOSABRUPT (PM073/2007), provided by the Diputación General de Aragón. Additional funding for XRD analyses (Univ. of Cádiz) and geochemical analyses (EEZ-CSIC and MARUM Centre) was provided by the Aragonese Regional Government – CAJA INMACULADA by means of 2 travel grants. M. Morellón and J.P. Corella are supported by PhD contracts with the CONAIþ D (Aragonese Scientific Council for Research and Development) and A. Moreno and M. Rico hold post-doctoral contracts funded by the ESF ('Marie Curie programme') and the Spanish Ministry of Science and Innovation ('Juan de la Cierva programme'), respectively. ; Peer reviewed

30 páginas, 9 figuras, 3 tablas.- El PDF del artículo es su versión post-print. ; A multi-proxy study of short sediment cores recovered in small, karstic Lake Estanya (42°02′ N, 0°32′ E, 670 m.a.s.l.) in the Pre-Pyrenean Ranges (NE Spain) provides a detailed record of the complex environmental, hydrological and anthropogenic interactions occurring in the area since medieval times. The integration of sedimentary facies, elemental and isotopic geochemistry, and biological proxies (diatoms, chironomids and pollen), together with a robust chronological control, provided by AMS radiocarbon dating and 210Pb and 137Cs radiometric techniques, enabled precise reconstruction of the main phases of environmental change, associated with the Medieval Warm Period (MWP), the Little Ice Age (LIA) and the industrial era. Shallow lake levels and saline conditions with poor development of littoral environments prevailed during medieval times (1150–1300 AD). Generally higher water levels and more dilute waters occurred during the LIA (1300–1850 AD), although this period shows a complex internal paleohydrological structure and is contemporaneous with a gradual increase of farming activity. Maximum lake levels and flooding of the current littoral shelf occurred during the nineteenth century, coinciding with the maximum expansion of agriculture in the area and prior to the last cold phase of the LIA. Finally, declining lake levels during the twentieth century, coinciding with a decrease in human pressure, are associated with warmer climate conditions. A strong link with solar irradiance is suggested by the coherence between periods of more positive water balance and phases of reduced solar activity. Changes in winter precipitation and dominance of NAO negative phases would be responsible for wet LIA conditions in western Mediterranean regions. The main environmental stages recorded in Lake Estanya are consistent with Western Mediterranean continental records, and show similarities with both Central and NE Iberian reconstructions, reflecting a strong climatic control of the hydrological and anthropogenic changes during the last 800 years. ; This research was funded through the projects LIMNOCAL (CGL2006-13327-C04-01), PALEODIVERSITAS (CGL2006-02956/BOS), GRACCIE (CSD2007- 00067) supported by the Spanish Inter-Ministry Commission of Science and Technology (CICYT); and PM073/2007 provided by the Diputación General de Aragón. The Aragonese Regional Government and CAJA INMACULADA provided two travel grants for the analyses carried out at Univ. of Cádiz and EEZ-CSIC (Spain), and MARUM Centre (Univ. of Bremen, Germany). M. Morellón was supported by a PhD contract with the CONAI + D (Aragonese Scientific Council for Research and Development). ; Peer reviewed