Scale dependence in habitat selection: the case of the endangered brown bear (Ursus arctos) in the Cantabrian Range (NW Spain)     

María C. Mateo Sánchez  Samuel A. Cushman  Santiago Saura 《International journal of geographical information science》2014,28(8):1531-1546

Animals select habitat resources at multiple spatial scales. Thus, explicit attention to scale dependency in species–habitat relationships is critical to understand the habitat suitability patterns as perceived by organisms in complex landscapes. Identification of the scales at which particular environmental variables influence habitat selection may be as important as the selection of variables themselves. In this study, we combined bivariate scaling and Maximum entropy (Maxent) modeling to investigate multiscale habitat selection of endangered brown bear (Ursus arctos) populations in northwest Spain. Bivariate scaling showed that the strength of apparent habitat relationships was highly sensitive to the scale at which predictor variables are evaluated. Maxent models on the optimal scale for each variable suggested that landscape composition together with human disturbances was dominant drivers of bear habitat selection, while habitat configuration and edge effects were substantially less influential. We found that explicitly optimizing the scale of habitat suitability models considerably improved single-scale modeling in terms of model performance and spatial prediction. We found that patterns of brown bear habitat suitability represent the cumulative influence of habitat selection across a broad range of scales, from local resources within habitat patches to the landscape composition at broader spatial scales.  相似文献   

High-resolution sea wind hindcasts over the Mediterranean area   总被引：1，自引：1，他引：0  

M. Menendez  M. García-Díez  L. Fita  J. Fernández  F. J. Méndez  J. M. Gutiérrez 《Climate Dynamics》2014,42(7-8):1857-1872

The goal of this study is to develop a high-resolution atmospheric hindcast over the Mediterranean area using the WRF-ARW model, focusing on offshore surface wind fields. In order to choose the most adequate model configuration, the study provides details on the calibration of the experimental saet-up through a sensitivity test considering the October–December 2001 period (the 2001 super-storm event in the West Mediterranean). A daily forecast outperforms the spectral technique of previous products and the boundary data from ERA-Interim reanalysis produces the most accurate estimates in terms of wind variability and hour-to-hour correspondence. According to the sensitivity test, two data sets of wind hindcast are produced: the SeaWind I (30-km horizontal resolution for a period of 60 years) and the SeaWind II (15-km horizontal resolution for 20 years). The validation of the resulting surface winds is undertaken considering two offshore observational datasets. On the one hand, hourly surface buoy stations are used to validate wind time series at specific locations; on the other hand, wind altimeter satellite observations are considered for spatial validation in the whole Mediterranean Sea. The results obtained from this validation process show a very good agreement with observations for the southern Europe region. Finally, SeaWind I and II are used to characterize offshore wind fields in the Mediterranean Sea. The statistical structure of sea surface wind is analyzed and the agreement with Weibull probability distribution is discussed. In addition, wind persistence and extreme wind speed (50 year return period) are characterized and relevant areas of wind power generation are described by estimating wind energy quantities.  相似文献   

Forest fire danger projections in the Mediterranean using ENSEMBLES regional climate change scenarios   总被引：1，自引：1，他引：0  

J. Bedia  S. Herrera  A. Camia  J. M. Moreno  J. M. Gutiérrez 《Climatic change》2014,122(1-2):185-199

We present future fire danger scenarios for the countries bordering the Mediterranean areas of Europe and north Africa building on a multi-model ensemble of state-of-the-art regional climate projections from the EU-funded project ENSEMBLES. Fire danger is estimated using the Canadian Forest Fire Weather Index (FWI) System and a related set of indices. To overcome some of the limitations of ENSEMBLES data for their application on the FWI System—recently highlighted in a previous study by Herrera et al. (Clim Chang 118:827–840, 2013)—we used an optimal proxy variable combination. A robust assessment of future fire danger projections is undertaken by disentangling the climate change signal from the uncertainty derived from the multi-model ensemble, unveiling a positive signal of fire danger potential over large areas of the Mediterranean. The increase in the fire danger signal is accentuated towards the latest part of the transient period, thus pointing to an elevated fire potential in the region with time. The fire-climate links under present and future conditions are further discussed building upon observed climate data and burned area records along a representative climatic gradient within the study region.  相似文献   

Estimating flash flood discharge in an ungauged mountain catchment with 2D hydraulic models and dendrogeomorphic palaeostage indicators   总被引：1，自引：0，他引：1  

J. A. Ballesteros Cánovas  M. Eguibar  J. M. Bodoque  A. Díez‐Herrero  M. Stoffel  I. Gutiérrez‐Pérez 《水文研究》2011,25(6):970-979

There is still wide uncertainty about past flash‐flood processes in mountain regions owing to the lack of systematic databases on former events. This paper presents a methodology to reconstruct peak discharge of flash floods and illustrates a case in an ungauged catchment in the Spanish Central System. The use of dendrogeomorphic evidence (i.e. scars on trees) together with the combined use of a two‐dimensional (2D) numerical hydraulic model and a terrestrial laser scan (TLS) has allowed estimation of peak discharge of a recent flash flood. The size and height distribution of scars observed in the field have been used to define three hypothetical scenarios (S_min or minimum scenario; S_med or medium scenario; and S_max or maximum scenario), thus illustrating the uncertainty involved in peak‐discharge estimation of flash floods in ungauged torrents. All scars analysed with dendrogeomorphic techniques stem from a large flash flood which took place on 17 December 1997. On the basis of the scenarios, peak discharge is estimated to 79 ± 14 m³ s^?1. The average deviation obtained between flood stage and expected scar height was ? 0·09 ± 0·53 m. From the data, it becomes obvious that the geomorphic position of trees is the main factor controlling deviation rate. In this sense, scars with minimum deviation were located on trees growing in exposed locations, especially on unruffled bedrock where the model predicts higher specific kinetic energy. The approach used in this study demonstrates the potential of tree‐ring analysis in palaeohydrology and for flood‐risk assessment in catchments with vulnerable goods and infrastructure. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

The Mid-Rivera-Transform Discordance: Morphology and Tectonic Development     

William L. Bandy  Fran?ois Michaud  Carlos A. Mortera Guti��rrez  J��r?me Dyment  Jacques Bourgois  Jean-Yves Royer  Thierry Calmus  Marc Sosson  Jose Ortega-Ramirez 《Pure and Applied Geophysics》2011,168(8-9):1391-1413

To better define the morphotectonic elements and tectonic development of the Mid-Rivera-Transform Discordance, multibeam bathymetric, seafloor backscatter, multichannel seismic reflection and total field marine magnetic data were collected along the entire Rivera Transform west of 107°W during the BART and FAMEX campaigns of the N.O. L??Atalante conducted in 2002. These data show that, although the transform tectonized zone of the Rivera Transform west of 107°30??W is a single continuous morphologic basin, this basin consists of two distinct morphotectonic domains: an eastern domain which morphologically is a deep rhombochasm within which organized seafloor spreading has occurred, and a western ??leaky transform?? domain. These new data, in conjunction with the results of previous studies, support the idea that the Rivera-Pacific Euler pole is migrating southward towards the eastern half of the Rivera Transform, and further indicate a recent (<0.14?Ma), and most likely ongoing, clockwise reorganization of the principle transform displacement zones of the Rivera Transform west of 108°W. We propose that the Mid-Rivera-Transform Discordance owes its origin to this eastward progressing, clockwise reorganization of the transform segments that is occurring in response to recent changes in Rivera-Pacific relative plate motion.  相似文献   

The rip current hazard in Costa Rica   总被引：1，自引：1，他引：0  

Isabel Arozarena  Chris Houser  Alejandro Gutiérrez Echeverria  Christian Brannstrom 《Natural Hazards》2015,77(2):753-768

  相似文献   

Integrated geophysical and morphostratigraphic approach to investigate a coseismic (?) translational slide responsible for the destruction of the Montclús village (Spanish Pyrenees)     

M. Zarroca  R. Linares  C. Roqué  J. Rosell  F. Gutiérrez 《Landslides》2014,11(4):655-671

A 12 million of m³ translational rockslide developed on a dip slope underlain by limestone with interlayered marls, and responsible for the destruction of the Montclús village in the fourteenth century, has been investigated by means of geomorphological and geophysical surveys. The combination of historical-geoarcheological, geomorphological, seismic refraction and electrical resistivity imaging datasets allowed the (1) reconstruction of the late Quaternary episodic evolution of the landslide, (2) characterization of the geometry and internal structure of the slid mass and (3) identification of preferential groundwater flow paths that favoured slope instability. The development of the landslide involved at least two different displacement episodes controlled by sliding surfaces at successively deeper stratigraphic positions. The first landsliding event, recorded by highly weathered landslide deposits situated above a perched failure plane, occurred approximately during the global Last Glacial Maximum (23–19 ka BP). The most recent event, which destroyed the Montclús village built on already slid rocks, is placed in the fourteenth century. Most probably, this reactivation event was triggered by the 1373 Ribagorza earthquake, with an estimated moment magnitude of M _w 6.2. This work illustrates the benefits of combining geomorphological data with complementary geophysical technics in landslide investigation.  相似文献   

In Situ Response of Phytoplankton to Nutrient Additions in a Tropical Coastal Lagoon, (La Mancha,Veracruz, Mexico)     

Francisco Varona-Cordero  Francisco J. Gutiérrez-Mendieta  Victor H. Rivera-Monroy 《Estuaries and Coasts》2014,37(6):1353-1375

An experimental in situ microcosm study was conducted in the tropical lagoon La Mancha (Gulf of Mexico) to determine whether or not nutrient limitation occurs and to examine the direct effect of an inorganic nutrient pulse on the phytoplankton community structure. The phytoplankton community response to the addition of four treatments with different combinations of nitrogen (N), phosphorus (P), and silica (Si) (+N-NH₄ ⁺, +P-PO₄ ^?, +Si-SO₃, and N:P16) showed that phytoplankton was N-limited as indicated by an increase in phytoplankton biomass (i.e., chlorophyll a) (range, 8–34 mg m^?3) during the dry season in two consecutive years (2006 and 2007). Picophytoplankton abundance significantly increased in the +N treatment (145.46 10³ cells L^?1), while microphytoplankton reached a maximum abundance (68.38 10³ cells L^?1) in the N:P16 treatment. Phytoplankton composition changed from a community initially dominated by dinoflagellates (e.g., Prorocentrum spp.) to another dominated by diatoms (Thalassiosira and Nitzschia longissima) in the N:P16 treatment. The +N treatment significantly increased Synechococcus sp. growth rates (1.3 divisions per day) (picocyanobacteria). Biomarker pigments measured in the experimental microcosms confirmed observed changes in phytoplankton groups. Our results reveal that La Mancha lagoon is a N-limited coastal system during the dry season and provides evidence of the temporal species successional patterns and mechanisms regulating the phytoplankton community response to nutrient enrichment pulses in this already eutrophic coastal lagoon.  相似文献   

A case of man-induced ground subsidence and building settlement related to karstified gypsum (Oviedo,NW Spain)     

Luis?PandoEmail author  Javier?A.?Pulgar  Manuel?Gutiérrez-Claverol 《Environmental Earth Sciences》2013,69(2):507-521

Within the TERENO initiative, four terrestrial observatories, collecting huge amounts of environmental data, are being set up since 2008. To manage, describe, exchange and publish these data, the distributed Spatial Data Infrastructure TEODOOR (http://www.tereno.net) was created. Each institution responsible for an individual observatory sets up its own local data infrastructure, which may communicate with each other to exchange data and metadata internally or to the public by OGC compliant Web services. The TEODOOR data portal serves as a database node to provide scientists and decision makers with reliable and well-accessible data and data products. Various tools like hierarchical search or Web-GIS functions allow a deeper insight into the different observatories, test sites and sensor networks. Sensor data can be queried and selected for measured parameters, stations and/or time periods, and can be visualized and downloaded according to a shared TERENO data policy. Currently, TEODOOR provides free access to data from more than 500 monitoring stations.  相似文献   

Discussion on the article “Paleoseismological analysis of an intraplate extensional structure: the Concud fault (Iberian Chain,Eastern Spain)” by P. Lafuente,L. E. Arlegui,C. L. Liesa,and J. L. Simón (Int J Earth Sci)     

Francisco Gutiérrez  Pedro Lucha  Jesús Guerrero  Mateo Gutiérrez  Domingo Carbonel 《International Journal of Earth Sciences》2012,101(2):579-585

This discussion is focused on three aspects of the paper published by Lafuente et al. (Int J Earth Sci, doi: 10.1007/s00531-010-0542-1, 2010) on Concud Fault, constitute the fundamental basis to assess the seismic potential of this capable structure: (1) A slip rate estimated for the Concud Fault based on an erroneous displacement value and a questionable correlation, obviating previously published datings, markedly different to those used by the authors. The wrong displacement value introduces an error of more than 25% in the calculated Quaternary slip rate. (2) A new paleoseismological interpretation of the outcrop of Condud Fault at Los Baños, adding two improperly justified paleoearthquakes to the four events previously inferred. (3) The attribution of faults affecting a young terrace to the most recent recorded earthquake on Concud Fault, ruling out implicitly the likely option of a gravitational origin for them, either landsliding or subsidence due to evaporite dissolution.  相似文献