52 research outputs found

    Estudio palinológico de la turbera do río das Furnas (Lugo)

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    Se ha realizado cliUI~IWs políntco de una tu1bera ~tuada en bs Sierras septenlrionalC$ gallegas. t...o.-. resultados ob4en!dos rc\·clan una progresiva defores~ oción (dlsminuci6n de QIICtr!IS r CCNyfiU, principalment e) Q\IC ~ intensifica hacia las fa!.ec; mác; recientes y cuJrnina con el <Jes..1rrollu de la estepa cullural haci:1 el 2lJ00-2SOO 8.P. En los e.spcclru:, supcrftcialcs Jos ta:cone.c; predominantes son Piaus pimmtr y Ericacc:\c..A poller1 nnalysi~ of pco1 bog c:ollcctcd in seplt nlrional Sierra.ío or O:~.hciJ, hn,_ bccn madc. Thc: resulu ~how a progre~iv~ tle.forr.:st:ltion (diminulion oí Quetws, Cory!1ts principally) wbicb ls inltn~i fied loward\ recen! l,bJlCS and rcachcs iu hig.h~l poinl ""~1 h 1hc cukural Sleppc ;~bout 2.600-2.500 8 P. PUuu pimalu and Ericacc~u:. pollen to deu ch in thc surfacc spedrurn

    Modificaciones de la vegetación y del paisaje litoral del NW Ibérico en relación con los cambios climáticos ocurridos en la transición entre los estadios isotópicos 3 y 2. El depósito pleistoceno de Caamaño

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    XV lnternational A.P.L.E. Symposium of Palynolog

    Formation of PoIycyclic Soils During the Recent Quaternary on Monte Borrelho (Northern Portugal)

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    [Abstract] Pedological and palynological characterization oftwo soils from Monte Borrelho (northern Portugal) evidences the formation ofpolycyclic soils in the Subatlantic. In both soils, two cycles are clearly separated by a stone line which may have resulted either from climatic deterioration or because human activity led to severe deforestation and the consequent preferential development ofherbaceous and shrub vegetation. Either cause would have favoured intense erosion, removing part of the upper A horizon of the pre-existing soils and giving rise to profiles with polycyclic characteristics

    New multiproxy data obtained from the sedimentary fill of the Ría de Ferrol, NW Iberia

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    Several gravity cores and vibro-cores were recovered from selected sites in the inner sector of Ría de Ferrol, NW Iberia (Muñoz Sobrino et al., 2021) [1]. These sediment cores were obtained during the surveys ECOMER-2014 and ECOMER-2015, developed from 2014 to 2015 on-board the R/V Mytilus (Consejo Superior de Investigación Científica) and the Amarradores Mil (Amarradores del Puerto y Ría de Ferrol, S.L.), respectively. Sedimentary and other multiproxy data presented here belong to four selected sediment cores located in the innermost part of the study area. Two were recovered using a gravity corer and another two using a vibro-corer. The depth of the cores and samples obtained is referred to the NMMA (the mean sea level in Alicante), which is the Spanish orthometric datum. One half of each core was subjected to non-destructive analysis using an ITRAX core scanner providing X-ray fluorescence (XRF) elemental data. Particle size distribution was characterised by laser diffraction. For radiocarbon dating, well-preserved articulated valves, small remains of wood and very organic bulk sediment from one location free of biogenic gas were selected. Palynological analyses were performed on selected sections of the sediment. All samples were spiked with Lycopodium spores for absolute palynomorph estimation and analysed using 400x and 600x magnifications. The ratio of dinoflagellate cyst concentrations to pollen, fern spore and dinoflagellate cyst concentrations (D/P ratio, ranging between 0 and 1) was calculated for each sample to show the temporal variation. Combined seismic, lithological, elemental, chronological and palynological data enable reconstructing the environmental changes that occurred during the local marine transgression. Besides, the combination of evidence identified may also be applied to other areas or periods in order to perform local reconstructions of changing coastal ecosystems. This type of high-resolution spatial-temporal reconstructions of past changes in estuarine environments may be a valuable tool for modelling, predicting and managing the changes and threats linked to the global warming and sea-level rise associated

    Geo‐Hydromorphological Assessment of Europe’s Southernmost Blanket Bogs

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    Blanket bogs are a globally rare type of ombrotrophic peatland internationally recognised for long‐term terrestrial carbon storage, the potential to serve as carbon sinks, habitat provision and for their palaeoenvironmental archive. This habitat is protected in the European Union under the Habitats Directive (92/43/EEC), but a number of blanket bogs located in the Cantabrian Mountains (northern Spain), representing the southernmost known edge‐of‐range for this habitat in Europe, are currently not recognised and are at increased threat of loss. Using climatic data, topography, aerial photography and peat depth surveys, this study has identified ten new areas of blanket bog located between the administrative regions of Cantabria and Castilla y León. Peat depth data and topography were used to provide a detailed geomorphological description and hydromorphological classification (mesotope units) of these currently unrecognised areas of blanket bog. Maximum peat depth measured across the ten sites ranged from 1.61 m to 3.78 m covering a total area of 18.6 ha of blanket bog (> 40 cm peat depth). The volume of peat accumulated across the sites was determined to be more than 216,000 m3 and is estimated to hold 19.89 ± 3.51kt C. Twenty‐four individual hydrological mesotope units were described indicating a diverse assemblage of blanket bogs in this region. The peatlands identified in this research extend the known limit of blanket bogs in Europe farther south than previously recorded and combined with four other unprotected blanket bogs recently identified in the Cantabrian Mountains, these peatlands represent 10.5% of blanket bog currently recognised and protected in Spain. The range of anthropogenic pressures currently acting on peatlands in the Cantabrian Mountains indicates that without protection these important landforms and carbon stored may be lost. An urgent update of European peatland inventories is thus required to preserve these valuable carbon stores and potential carbon sinks

    The timing of the postglacial marine transgression in the Ría de Ferrol (NW Iberia): A new multiproxy approach from its sedimentary infill

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    The Ría de Ferrol is a confined tide-dominated incised valley in the mesotidal passive Atlantic margin of NW Iberia. A new multidisciplinary approach enables a high-resolution reconstruction of the main environmental changes affecting this area during the Lateglacial and the Holocene. We defined the main seismic and sedimentary facies in the infill and selected different key points to be cored. A number of multiproxy analyses were performed on four sections of sediment (sedimentology, X-ray fluorescence, radiocarbon dating and palynological analyses). Physiography exerted a strong control on the evolution of the basin, as a rock-bounded narrow channel in the middle of the basin influenced the flooding of the ria during the postglacial marine transgression. Depositional environments shifted towards the east as the sea level rose and fluvial facies at the base were covered by facies from a tide-dominated estuary, which were predominant during most of the Holocene. Several layers of sediments from stagnant freshwater areas dominated by Juncus sp. were recovered at ca. −20.5 to −21, ca. −13.1 to −13.5, −12.5 to −12.8 and −12.1 to −13.5 m NMMA along the central axis of the embayment, and dated to be older than 10190–10290; 10790–10970; 7510–8220 and 7130–7830 cal yr BP. They may respectively represent a local stage of lowering sea-level dated at the end of the Lateglacial (i.e. the Younger Dryas), and different episodes of deceleration/stabilization of sea-level rise occurred during the early Holocene (i.e. the 11.4, 10.5, 9.3, 8.2 kyr Henrich events). Thus, for the first time in this region, we were able to generate a high-resolution spatial–temporal interpretation of environmental changes linked to the relative sea-level variations using subtidal sediments from the same sub-basin (and thus free of substantial/differential post-depositional deformations) that describes in detail the flooding of the ancient coastal plains of this region at the beginning of the Holocene

    Identificación de los Indicadores de seguimiento de las acciones de conservación. Acción A1 “Diagnosis, Análisis territorial e Identificación de Indicadores"

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    Las acciones de conservación de LIFE FLUVIAL precisan de una evaluación periódica de sus repercusiones sobre el hábitat 91E0* y el hábitat 9230 (los dos hábitats objetivo del proyecto). Cada socio en sus territorios debe llevar a cabo un seguimiento con motivo de la acción D1 que permita evaluar la efectividad de las actuaciones de restauración (acciones C) y realizar una toma de decisiones de acuerdo a los resultados de dicho monitoreo, que pueda incluir cambios en las actuaciones previstas o la ejecución de nuevas medidas. En consecuencia, en el presente documento se establecen los indicadores de seguimiento a emplear en la acción D1 de LIFE FLUVIAL, así como la metodología para su aplicación. Los objetivos del seguimiento son: A. Vigilar la evolución del proceso de restauración B. Controlar los cambios que se produzcan C. Detectar y corregir la aparición de efectos indeseables D. Favorecer los procesos que se entiendan beneficiosos para recuperar la naturalidad y biodiversidad del lugar. En todo caso, hay que tener en cuenta que la duración del proyecto se queda corta para poder abarcar todo el proceso de recuperación de la cubierta vegetal propiciado por las acciones de conservación, de modo que, probablemente, los resultados del seguimiento relativos a algunos parámetros no presentarán valores especialmente significativos, debiendo interpretarse entonces como tendencias de la evolución de los hábitats objetivo en los enclaves de actuación.info:eu-repo/semantics/publishedVersio

    Revealing the last 13,500 years of environmental history from the multiproxy record of a mountain lake (Lago Enol, northern Iberian Peninsula)

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    This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s10933-009-9387-7.We present the Holocene sequence from Lago Enol (43°16′N, 4°59′W, 1,070 m a.s.l.), Cantabrian Mountains, northern Spain. A multiproxy analysis provided comprehensive information about regional humidity and temperature changes. The analysis included sedimentological descriptions, physical properties, organic carbon and carbonate content, mineralogy and geochemical composition together with biological proxies including diatom and ostracod assemblages. A detailed pollen study enabled reconstruction of variations in vegetation cover, which were interpreted in the context of climate changes and human impact. Four distinct stages were recognized for the last 13,500 years: (1) a cold and dry episode that includes the Younger Dryas event (13,500–11,600 cal. year BP); (2) a humid and warmer period characterizing the onset of the Holocene (11,600–8,700 cal. year BP); (3) a tendency toward a drier climate during the middle Holocene (8,700–4,650 cal. year BP); and (4) a return to humid conditions following landscape modification by human activity (pastoral activities, deforestation) in the late Holocene (4,650–2,200 cal. year BP). Superimposed on relatively stable landscape conditions (e.g. maintenance of well established forests), the typical environmental variability of the southern European region is observed at this site.The Spanish Inter-Ministry Commission of Science and Technology (CICYT), the Spanish National Parks agency, the European Commission, the Spanish Ministry of Science, and the European Social Fund

    Revealing the last 13,500 years of environmental history from the multiproxy record of a mountain lake (Lago Enol, northern Iberian Peninsula)

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    This is the author's accepted manuscript. The final publication is available at Springer via http://dx.doi.org/10.1007/s10933-009-9387-7.We present the Holocene sequence from Lago Enol (43°16′N, 4°59′W, 1,070 m a.s.l.), Cantabrian Mountains, northern Spain. A multiproxy analysis provided comprehensive information about regional humidity and temperature changes. The analysis included sedimentological descriptions, physical properties, organic carbon and carbonate content, mineralogy and geochemical composition together with biological proxies including diatom and ostracod assemblages. A detailed pollen study enabled reconstruction of variations in vegetation cover, which were interpreted in the context of climate changes and human impact. Four distinct stages were recognized for the last 13,500 years: (1) a cold and dry episode that includes the Younger Dryas event (13,500–11,600 cal. year BP); (2) a humid and warmer period characterizing the onset of the Holocene (11,600–8,700 cal. year BP); (3) a tendency toward a drier climate during the middle Holocene (8,700–4,650 cal. year BP); and (4) a return to humid conditions following landscape modification by human activity (pastoral activities, deforestation) in the late Holocene (4,650–2,200 cal. year BP). Superimposed on relatively stable landscape conditions (e.g. maintenance of well established forests), the typical environmental variability of the southern European region is observed at this site.The Spanish Inter-Ministry Commission of Science and Technology (CICYT), the Spanish National Parks agency, the European Commission, the Spanish Ministry of Science, and the European Social Fund

    Introducción al patrimonio geológico de interés turístico de la Red Española de Reservas de la Biosfera

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    160 p.Esta publicación se ha realizado con el objetivo de describir el origen y formación de una buena parte del patrimonio geológico de interés turístico de la Red Española de Reservas de la Biosfera para que éste sea conocido y pueda ser utilizado como motor de desarrollo económico local. La necesidad de dar a conocer este sorprendente patrimonio natural de la Red español de Reservas de la Biosfera fue constatada por su Consejo de Gestores que encargó el trabajo a su Consejo Científico. La publicación tiene la vocación de ser accesible para todos los públicos. Sin embargo, parte de un trabajo bibliográfico profundo abordado con una rigurosa metodología científica. Es además el fruto de una continua colaboración de los editores con las personas gestoras de las Reservas de la Biosfera españolas, así como con varios miembros de su Consejo Científico asesor.Instituto Geológico y Minero de España, Españ
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