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Accurate assessment of soil loss is essential for sustainable agricultural production, management and conservation planning, especially in productive rain-fed agro-ecosystems and protected areas. The European Union considers soil as a non-renewable resource and identifies that soil degradation has strong impacts on soil and water resources. In this work the Revised Universal Soil Loss Equation model was applied within a geographic information system in the Estaña catchment (Spanish Pre-Pyrenees) as representative of a Mediterranean agro-ecosystem to elaborate a map of soil erosion at high spatial resolution (5 x 5 m of cell size). The soil erodibility factor (K) is calculated from three different approaches to evaluate the importance of spatial variations in soil texture, field infiltration measurements (Kfs) and amount of coarse fragments. The average value of estimated soil loss for the whole study area is 2.3 Mg ha-1 yr-1 and the highest rates are estimated in crops in steep areas (5.8 Mg ha-1 yr-1) and trails (18.7 Mg ha-1 yr-1). Cultivated soils with high soil erosion rates (higher than 8 Mg ha-1 yr-1) represent 20% of the cultivated area. The average value of soil loss in areas with human disturbances (4.21 Mg ha-1 yr-1) is 4.4 times higher than that estimated for areas with natural vegetation (0.96 Mg ha-1 yr-1). Field validation with 137Cs shows that the estimated value of soil loss in barley fields with the K-Kfs-rocks factor improves the model predictions in comparison with those obtained with the K-texture and K-Kfs factors. The RUSLE model predicts a decrease in soil erosion in fields in accordance with the increase of the age of abandonment. Predicted values of soil erosion and measured soil organic matter and stoniness in old abandoned fields agree with those in areas of natural forest and indicate the recovery of the original conditions of the soil. Statistical analysis highlights that the C factor contributes most of the variability of the values of predicted soil erosion, the K and LS factors contribute in a similar way and the P factor contributes least to the variability of soil erosion. Cultivated soils developed over clay materials in high slope areas are the most susceptible to soil degradation processes in comparison with soils developed over limestones in gentle and medium slope areas. The recovery of terraces in steep fields and conservation of crop residues are proposed as soil conservation practices to reduce the magnitude of soil loss in the study area. ; This research was financially supported by the following project: "Soil erosion and carbon dynamic in Mediterranean agroecosystems: radioisotopic modelling at different spatial and temporal scales" (MEDEROCAR, CGL2008-00831/BTE) funded by the Spanish Ministry of Science and Innovation. ; Peer reviewed

30 Págs., 7 Figs., 3 Tabls. Available online 15 September 2013. The definitive version is available at: http://link.springer.com/journal/12665 ; Soil moisture variability and the depth of water stored in the arable layer of the soil are important topics in agricultural research and rangeland management. In this study, we use the distributed rainfall-runoff (DR2) model to perform a detailed mapping of topsoil moisture status (SMS) in a mountain Mediterranean catchment. This model, previously tested in the same study area against the Palmer Z-index, is run at monthly scale for the current scenario of land uses and under three scenarios that combine the land abandonment and the application of the new common agricultural policy (CAP) of the European Union. Under the current conditions, runoff yield is scarce and presents a high spatial variability when monthly rainfall intensity and depth are low, and infiltration processes mainly lead to water storage in the soil. When rainfall intensity is high, runoff accumulation along the hillslopes controls the depth of available water in the soil, and SMS is more homogeneous. On average, scrublands and pasture have the wettest values, crops of winter cereal and abandoned fields have intermediate conditions, and areas of bare soil and forest have the driest conditions all the year around. The abandonment and no revegetation of the low productive fields located in steep areas and the collapse of their landscape linear elements (LLEs) produce not only an increase of 2.3 % of the overall SMS in the catchment in comparison with the current scenario but also an increment of the effective runoff that cross the cultivated areas of the lowlands and the runoff depth that reach the wetlands, increasing the soil erosion risk and compromising the conservation of the lakes. When the new green areas of the CAP are installed in the upper part of the fields of the lowlands and around the lakes, the runoff depth and thus siltation risk clearly decreases but also SMS decreases 1.7 and 1.1 % considering the current land uses and adding revegetation practices in the abandoned fields, respectively. Hence, a management scenario where: (1) abandoned fields are covered with a dense cover of shrubs, (2) the LLEs are preserved, (3) the green areas of the PAC are created, and (4) runoff harvesting practices are applied to partially compensate the water deficit, will help to preserve the humidity of the soil and will be of interest to keep the agricultural land use around the protected lakes of the study area. © 2013 Springer-Verlag Berlin Heidelberg. ; This research was funded by the Projects "Erosion and redistribution of soils and nutrients in Mediterranean agroecosystems: radioisotopic tracers of sources and sinks and modeling of scenarios (EROMED) (CGL2011-25486/BTE)" of the Spanish Ministry of Economy and Competitiveness (former Ministry of Science and Innovation) and "Mitigation of siltation of the Estaña Lakes Wetlands (Huesca, Spain) under different scenarios of climate change: soil and water trapping effectiveness of the "green areas" of the new CAP (Expedient number 2012 GA LC 034)" of the Regional Government of Aragón (Spain) and Obra Social "la Caixa" ; Peer reviewed

29 Pags., 3 Tabls., 6 Figs. The definitive version is available at: http://www.sciencedirect.com/science/journal/03783774 ; Hydrological and soil erosion models allow mapping and quantifying rates of runoff depths and soil redistribution for different land uses and climatic scenarios. Mediterranean soils are threatened by marked seasonal changes in the climatic, thus soil and vegetation parameters and modelling predictions at monthly scale are required. The semi-physically-based Soil Erosion and Redistribution Tool (SERT) model is presented together with the results of its application in a Mediterranean agro-ecosystem (NE Spain) with a detailed database. The hydrological module is based on the recently published DR2 (Distributed Rainfall-Runoff) water balance model and the effects of man-made infrastructures on the natural dynamics of runoff connectivity are added. The erosion module is built using, as the basis, the Revised Morgan, Morgan and Finney model, and the new Remaining runoff Transport Capacity (TCr) factor used to estimate the rates of soil loss and deposition. Predicted runoff depth varied in time and space, presenting areas without runoff production mainly in Rendzic Leptosols and Haplic Calcisols between November and April. Average soil erosion was high in cultivated and bare soils, ca. 20 and 10 Mg ha–1 yr–1, whereas rangeland soils were affected by moderate and, in some areas, by limited erosion processes. Soil erosion was minimal in February (0.08 Mg ha–1 month–1 on average) and 23 times higher in October. The SERT model allowed mapping the significant changes in the monthly values of soil redistribution quantifying the variability in the magnitude of the processes involved. Predicted values of average soil loss and deposition were validated against quantified values with 137Cs obtaining an average Nash–Sutcliffe efficiency of 0.48 (Pearson's r = 0.709) and a sediment balance of -1.15 Mg yr–1 for the whole catchment that is consistent with the karst processes of the study area. The new model is an easy-to-run, reliable, low-input-demanding management tool with valuable outputs for hydrological and soil erosion studies in small agricultural catchments. ; This research was funded by the Projects "Erosion and redistribution of soils and nutrients in Mediterranean agroecosystems: radioisotopic tracers of sources and sinks and modelling of scenarios (EROMED) (CGL2011-25486/BTE)" of the Spanish Ministry of Economy and Competitiveness (former Ministry of Science and Innovation) and "Mitigation of siltation of the Estaña Lakes Wetlands (Huesca, Spain) under different scenarios of climate change: soil and water trapping effectiveness of the "green areas" of the new CAP (Expedient number 2012 GA LC 034)" of the Regional Government of Aragón (Spain) and Obra Social "la Caixa". ; Peer reviewed

27 Pags., 5 Tabls., 8 Figs. The definitive version is available at: http://www.jswconline.org/ ; Assessment of the spatial distribution of soil properties has achieved considerable interest among soil scientists, both for testing hypotheses about soil formation processes and for predicting the properties of soils at nonsampled locations (mapping). In this paper, we provide a discussion of the various approaches to the modeling of spatial variates, and we propose a modeling framework that is able to incorporate the most important effects usually found in spatial variates, including fixed and random spatial effects, spatial trends, and heteroscedasticity. We provide a case study of the analysis of eight soil properties in a mountain catchment in the Spanish Pyrenees. As explanatory covariates, we use several topography parameters, which can be related to the pedogenetic processes active in the area. Several of them proved useful for explaining the variability of soil properties, explaining up to 77% of their variance. We focus on the importance of model selection in order to determine which effects are relevant for modeling each soil parameter. We find that the full model is not necessarily optimal for all the variables tested and that the model should be adapted to the complexity of each individual case. This paper is a contribution to the discussion on the modeling of spatial variates and to the eventual development of a general theory of spatial variates. ; This work has been supported by the following research projects: EROMED (CGL2011-25486) and DISDROSPEC (CGL2011–24185) financed by the Spanish Commission of Science and Technology (CICYT) and FEDER, ChangingRISKS (OPE00446/PIM2010ECR-00726) financed by EU ERA-NET CIRCLE Programme, and Grupo de Excelencia E68 financed by the Aragón Government. Research of M. A.-M. is supported by a research grant from the Spanish National Research Council (JAE-Predoc, CSIC). ; Peer reviewed

Purpose: Sediment delivery from headwater catchments to reservoirs is a serious threat to reservoir sustainability, and is a critical issue in Mediterranean environments where water resources are scarce. In this study we assessed the consequences of two landscape management scenarios (natural vegetation recovery and scrub clearance) on soil erosion and sediment yield. The results were analyzed in relation to predicted and measured rates of soil erosion and sediment yield, with the aim of promoting better management practices. Materials and methods: The study area was the Arnás River catchment (284 ha), which is located in the central Spanish Pyrenees; the area includes abandoned and poorly managed fields. The combination of the RUSLE and SEDD models of soil erosion and sediment delivery was evaluated in terms of its ability to predict annual rates of sediment yield, using field measurement data for seven water years at the gauging station. The consequences of natural plant succession in other areas of the Spanish Pyrenees, and scrub clearance practices implemented by certain regional governments to increase grazing meadow areas and reduce the incidence of wildfires, were spatially analyzed using GIS. The main sediment source areas were identified and their specific and total sediment yield rates were calculated. Results and discussion: The predicted soil loss under existing conditions was 2.6 Mg ha–1 yr–1, with 5% of the surface area affected by rates greater than 2 tons. The measured sediment yield (SY) range was 69–534 Mg yr–1. The maximum SY detected was associated with an extraordinary debris flow. The predicted rates were strongly correlated to measured rates (Nash–Sutcliffe coefficient = 0.72). The main sources of were alluvial deposits (Specific Sediment Yield = 51 Mg ha–1 yr–1), bare soil (SSY = 12), unpaved trails (SSY = 11), lots (SSY = 4) and pastures (SSY = 1). Under a scenario of vegetation recovery, decreases of 3, 17 and 16% in soil loss, and sediment delivery and yield (respectively) are predicted, whereas increases of 15, 5 and 2% are predicted following scrub clearance practices. Conclusions: Coupling the RUSLE and SEDD models enabled estimation of annual values of soil erosion and delivery in monitored and unmonitored catchments of small and medium size, making this approach a useful tool for risk analysis. Management practices that combine fire-risk control, by the implementation of scrub clearance practices, with the effects of plant succession on the sediment production are suggested as the best management strategy. ; Acknowledgements: This research was financially supported by the projects: "Soil erosion and carbon dynamic in Mediterranean agroecosystems: radioisotopic modelling at different spatial and temporal scales" (MEDEROCAR, CGL2008-00831/BTE), and "Processes and sediment balances at different spatial scales in Mediterranean environments: Effects of climate fluctuations and land use changes" (PROBASE, CGL2006-11619/HID), both funded by the Spanish Ministry of Science and Innovation. Monitoring of the catchment was supported by an agreement between the CSIC and the Spanish Ministry of Environment (RESEL). ; Peer reviewed

14 Pags., 3 Tabls., 9 Figs. ; Soil erosion and sediment yield are strongly affected by land use/land cover (LULC). Spatially distributed erosion models are of great interest to assess the expected effect of LULC changes on soil erosion and sediment yield. However, they can only be applied if spatially distributed data is available for their calibration. In this study the soil erosion and sediment delivery model WATEM/SEDEM was applied to a small (2.84 km2) experimental catchment in the Central Spanish Pyrenees. Model calibration was performed based on a dataset of soil redistribution rates derived from point 137Cs inventories, allowing capture differences per land use in the main model parameters. Model calibration showed a good convergence to a global optimum in the parameter space, which was not possible to attain if only external (not spatially distributed) sediment yield data were available. Validation of the model results against seven years of recorded sediment yield at the catchment outlet was satisfactory. Two LULC scenarios were then modeled to reproduce land use at the beginning of the twentieth century and a hypothetic future scenario, and to compare the simulation results to the current LULC situation. The results show a reduction of about one order of magnitude in gross erosion (3180 to 350 Mg yr−1) and sediment delivery (11.2 to 1.2 Mg yr−1 ha−1) during the last decades as a result of the abandonment of traditional land uses (mostly agriculture) and subsequent vegetation recolonization. The simulation also allowed assessing differences in the sediment sources and sinks within the catchment. ; This work has been supported by the following research projects: MEDEROCAR (CGL2008-00831/BTE), EROMED (CGL2011-25486), and DISDROSPEC (CGL2011- 24185), financed by the Spanish Commission of Science and Technology (CICYT) and FEDER, ChangingRISKS (OPE00446/PIM2010ECR-00726), financed by EU ERA-NET CIRCLE Programme, and Grupo de Excelencia E68 financed by the Arag´on Government and FEDER. The research of M. A.-M. Contribution of L.-C. A. was made possible through a scholarship granted by The National Council for Science and Technology of Mexico (CONACYT). ; Peer reviewed

29 Pags.- 5 Figs.- 3 Tabls. Available online 7 September 2014. The definitive version is available at: http://www.sciencedirect.com/science/journal/13648152 ; Flow accumulation algorithms (FAAs) predict the cumulative upstream drainage but each FAA generates a different map and this uncertainty still remains unsolved. This study makes advances in flow path research by testing 8 FAAs and analyzing the uncertainties of 15 simulations. The DR2-2013© SAGAv1.0 hydrological software is presented in a study carried out for two catchment lakes (NE Spain) over a 69-month test period. The best simulations were obtained with two single flow (Rho8 and Deterministic Infinity) and two multiple flow (Multiple Flow with threshold value and Triangular Multiple Flow) algorithms. Correlations between runoff depths and lake levels improved when the test period was split into wet and dry seasons. Correlations also improved with a one-month delay in response time and no delay in the large and small lakes. The DR2-2013© tool helped predict changes in lake volume and the highest model efficiencies were obtained with the multiple flow algorithms. ; This research was funded by the Projects: i) "Mitigation of siltation of the Estaña Lakes Wetlands (Huesca, Spain) under different scenarios of climate change: soil and water trapping effectiveness of the "green areas" of the new CAP (2012 GA LC 034)" of the Regional Government of Aragón (Spain) and Obra Social "la Caixa"; ii) "Erosion and redistribution of soils and nutrients in Mediterranean agroecosystems: radioisotopic tracers of sources and sinks and modeling of scenarios (EROMED; CGL2011-25486/BTE)" of the Spanish Ministry of Economy and Competitiveness and iii) "Funcionamiento hidrológico de humedales relacionados con las aguas subterráneas en la cuenca del Ebro (2007–2010)" of the Spanish Geological Survey (IGME). ; 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

29 Pags.- 6 Tabls.- 6 Figs. This article belongs to a special issue of Catena titled "Geoecology in Mediterranean mountain areas. Tribute to Professor José María García Ruiz". The definitive version is available at: http://www.sciencedirect.com/science/journal/03418162 ; Understanding how organic carbon (OC) moves with sediments along the fluvial system is crucial to determining catchment scale carbon budgets and helps the proper management of fragile ecosystems. Especially challenging is the analysis of OC dynamics during fluvial transport in heterogeneous, fragile, and disturbed environments with ephemeral and intense hydrological pulses, typical of Mediterranean conditions. This paper explores the catchment scale OC redistribution by lateral flows in extreme Mediterranean environmental conditions, from a geomorphological perspective. The study area is a catchment (Cárcavo) in SE Spain with a semiarid climate, erodible lithologies, and shallow soils, which is highly disturbed by agricultural terraces, land levelling, reforestation, and construction of check-dams. To increase our understanding of catchment scale OC redistribution induced by erosion, we studied in detail the subcatchments of eight check-dams distributed along the catchments main channel. We determined 137Cs, physicochemical characteristics, and the OC pools of the catchment soils and sediments deposited behind each check-dam, performed spatial analysis of catchment properties and buffer areas around the check-dams, and carried out geomorphological analysis of the slope-channel connections. The soils showed very low total organic carbon (TOC) values, oscillating between 15.2 and 4.4 g kg− 1 for forest and agricultural soils, respectively. Sediments mobilized by erosion were poor in TOC (6.6 ± 0.7 g kg– 1) compared to the eroded (forest) soils, and the redistribution of OC through the catchment, especially of the mineral associated organic carbon (MAC) pool, showed the same pattern as clay particles and 137Cs. The TOC erosion rates estimated for the Cárcavo watershed are relatively low (0.031 ± 0.03 Mg ha− 1 y− 1) but similar to those reported for subhumid Mediterranean catchments that are less fragile and more conducive to plant growth. The TOC erosion/total erosion ratio was lower (0.06%) than other estimates, although the average OC concentration of the sediments was higher than that of the agricultural soils of the catchment, underlining the problem of maintaining sustainable soil OC contents. The OC in deposited sediments came not only from surface erosion processes, but also from deeper soil or sediment layers mobilized by concentrated erosion processes. Sediment richer in OC came from the surface soil of vegetated (reforested) areas close and well connected to the channels. Subcatchments dominated by laminar erosion processes showed a TOC erosion/total erosion ratio that was two times higher than that of subcatchments dominated by concentrated flow erosion processes. The lithology, soils, and geomorphology exert a more important control on OC redistribution than land use and vegetation cover in this geomorphologically very active catchment. ; This work was financially supported by the projects ADAPT (CGL2013-42009-R) and DISECO (CGL2014-55-405-R) from the Spanish Government, National Plan of Science; the project CAMBIO (18933/JLI/13) of the Seneca Foundation, Regional Government of Murcia (Spain); and the project SOGLO (P7/24 IAP BELSPO) from the Belgian Government. Joris de Vente was supported by a 'Ramón y Cajal' grant (RYC-2012-10375). ; 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

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