Development of a typology for transitional waters in the Mediterranean ecoregion: The case of the islands     

Paloma Lucena-Moya  Isabel Pardo  Maruxa Álvarez 《Estuarine, Coastal and Shelf Science》2009

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Trends and correlations in annual extreme precipitation indices for mainland Portugal, 1941–2007     

M. Isabel P. de Lima  Fátima Espírito Santo  Alexandre M. Ramos  Ricardo M. Trigo 《Theoretical and Applied Climatology》2015,119(1-2):55-75

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Evaluating the fitness for use of spatial data sets to promote quality in ecological assessment and monitoring     

Isabel Pôças  João Gonçalves  Bruno Marcos  Joaquim Alonso  Pedro Castro  João P. Honrado 《International journal of geographical information science》2014,28(11):2356-2371

This article proposes and illustrates a practical methodological framework to evaluate the fitness for use of spatial data sets for environmental and ecological applications, focusing on user requirements for specified application contexts. The methodology is based on the use of metadata to analyze similarity between the data characteristics and the user’s needs or expectations for several quality indicators. Additionally, the concept of ‘critical factors’ is introduced in this framework, allowing users to define which quality indicators have greater importance given their own requirements or expectations and the specified application contexts. The proposed methodology further allows integrating and interconnecting the spatial data quality (SDQ) evaluation methodology with metadata geoportals in WebGIS platforms, facilitating its operation by users from non-spatial disciplines and with often limited expertise on this subject. Examples of the evaluation of fitness for use for specific application contexts within the project BIO_SOS (‘Biodiversity Multi-SOurce Monitoring System: From Space To Species’ FP7 project) are presented. By providing a prompt and straightforward evaluation tool, the proposed methodology can encourage the implementation of SDQ evaluation routines in ecological assessment and monitoring programs, promoting a more adequate use of geospatial data and ultimately contributing to well-supported policy and management decisions.  相似文献   

Magnetic susceptibility and electrical conductivity as a proxy for evaluating soil contaminated with arsenic,cadmium and lead in a metallurgical area in the San Luis Potosi State,Mexico     

Isabel Pérez  Francisco Martín Romero  Olivia Zamora  Margarita Eugenia Gutiérrez-Ruiz 《Environmental Earth Sciences》2014,72(5):1521-1531

A total of 113 samples of waste and soil were collected from a site in the state of San Luis Potosi, Mexico, that was occupied for several years by the metallurgical industry. Specific magnetic susceptibility (MS), electrical conductivity (EC) and pH were determined, as well as the total and available concentrations of potentially toxic elements (PTEs) such as As, Cd, Cu, Fe, Pb and Zn, which may cause a health risk for humans, animals and ecosystems, and the concentrations of major ions in aqueous extracts of soils and wastes. The solid phases of the samples were also characterized. The results revealed that the soils and wastes exhibited elevated values of PTEs, MS and EC. For soils these values decreased with increasing distance from the waste storage sites. The MS values were elevated primarily due to the presence of Fe-oxyhydroxides, such as magnetite, hematite and goethite, which contain PTEs in their structure leading to a high correlation between the value of MS and the As, Cd, Fe and Pb contents (r = 0.57–0.91) as well as between the PTEs values (r = 0.68–0.92). The elevated EC values measured in the metallurgical wastes were the result of presence of the sulfate minerals of Ca, Mg and Fe. The pollution index, which indicates the levels of simultaneous toxicity from elements such as As, Cd and Pb, was determined, with extreme hazard zones corresponding to areas that exhibit high MS values (0.91 correlation). In conclusion, MS measurements can be used as an indirect indicator to evaluate the PTE contamination in metallurgical areas, and EC measurements can aid in the identification of pollution sources.  相似文献   

How accurately are climatological characteristics and surface water and energy balances represented for the Colombian Caribbean Catchment Basin?     

Isabel Hoyos  Astrid Baquero-Bernal  Stefan Hagemann 《Climate Dynamics》2013,41(5-6):1269-1290

In Colombia, the access to climate related observational data is restricted and their quantity is limited. But information about the current climate is fundamental for studies on present and future climate changes and their impacts. In this respect, this information is especially important over the Colombian Caribbean Catchment Basin (CCCB) that comprises over 80 % of the population of Colombia and produces about 85 % of its GDP. Consequently, an ensemble of several datasets has been evaluated and compared with respect to their capability to represent the climate over the CCCB. The comparison includes observations, reconstructed data (CPC, Delaware), reanalyses (ERA-40, NCEP/NCAR), and simulated data produced with the regional climate model REMO. The capabilities to represent the average annual state, the seasonal cycle, and the interannual variability are investigated. The analyses focus on surface air temperature and precipitation as well as on surface water and energy balances. On one hand the CCCB characteristics poses some difficulties to the datasets as the CCCB includes a mountainous region with three mountain ranges, where the dynamical core of models and model parameterizations can fail. On the other hand, it has the most dense network of stations, with the longest records, in the country. The results can be summarised as follows: all of the datasets demonstrate a cold bias in the average temperature of CCCB. However, the variability of the average temperature of CCCB is most poorly represented by the NCEP/NCAR dataset. The average precipitation in CCCB is overestimated by all datasets. For the ERA-40, NCEP/NCAR, and REMO datasets, the amplitude of the annual cycle is extremely high. The variability of the average precipitation in CCCB is better represented by the reconstructed data of CPC and Delaware, as well as by NCEP/NCAR. Regarding the capability to represent the spatial behaviour of CCCB, temperature is better represented by Delaware and REMO, while precipitation is better represented by Delaware. Among the three datasets that permit an analysis of surface water and energy balances (REMO, ERA-40, and NCEP/NCAR), REMO best demonstrates the closure property of the surface water balance within the basin, while NCEP/NCAR does not demonstrate this property well. The three datasets represent the energy balance fairly well, although some inconsistencies were found in the individual balance components for NCEP/NCAR.  相似文献   

Winter-to-spring temperature dynamics in Turkey derived from tree rings since AD 1125   总被引：2，自引：1，他引：1  

Ingo Heinrich  Ramzi Touchan  Isabel Dorado Liñán  Heinz Vos  Gerhard Helle 《Climate Dynamics》2013,41(7-8):1685-1701

In the eastern Mediterranean in general and in Turkey in particular, temperature reconstructions based on tree rings have not been achieved so far. Furthermore, centennial-long chronologies of stable isotopes are generally also missing. Recent studies have identified the tree species Juniperus excelsa as one of the most promising tree species in Turkey for developing long climate sensitive stable carbon isotope chronologies because this species is long-living and thus has the ability to capture low-frequency climate signals. We were able to develop a statistically robust, precisely dated and annually resolved chronology back to AD 1125. We proved that variability of δ¹³C in tree rings of J. excelsa is mainly dependent on winter-to-spring temperatures (January–May). Low-frequency trends, which were associated with the medieval warm period and the little ice age, were identified in the winter-to-spring temperature reconstruction, however, the twentieth century warming trend found elsewhere could not be identified in our proxy record, nor was it found in the corresponding meteorological data used for our study. Comparisons with other northern-hemispherical proxy data showed that similar low-frequency signals are present until the beginning of the twentieth century when the other proxies derived from further north indicate a significant warming while the winter-to-spring temperature proxy from SW-Turkey does not. Correlation analyses including our temperature reconstruction and seven well-known climate indices suggest that various atmospheric oscillation patterns are capable of influencing the temperature variations in SW-Turkey.  相似文献   

Enzymatic activity in the rhizosphere of Spartina maritima: potential contribution for phytoremediation of metals   总被引：2，自引：0，他引：2  

Reboreda R  Caçador I 《Marine environmental research》2008,65(1):77-84

Extracellular enzymatic activity (EEA) of five enzymes (peroxidase, phenol oxidase, beta-glucosidase, beta-N-acetylglucosaminidase and acid phosphatase) was analysed in sediments colonised by Spartina maritima in two salt marshes (Rosário and Pancas) of the Tagus estuary (Portugal) with different characteristics such as sediment parameters and metal contaminant levels. Our aim was a better understanding of the influence of the halophyte on microbial activity in the rhizosphere under different site conditions, and its potential consequences for metal cycling and phytoremediation in salt marshes. Acid phosphatase and beta-N-acetylglucosaminidase presented significantly higher EEA in Rosário than in Pancas, whereas the opposite occurred for peroxidase. This was mainly attributed to differences in organic matter between the two sites. A positive correlation between root biomass and EEA of hydrolases (beta-glucosidase, beta-N-acetylglucosaminidase and acid phosphatase) was found, indicating a possible influence of the halophyte in sediment microbial function. This would potentially affect metal cycling in the rhizosphere through microbial reactions.  相似文献   

Varre-Sai: The Recent Brazilian Fall     

M. E. Zucolotto  L. L. Antonello  M. E. Varela  R. B. Scorzelli  P. Munayco  E. dos Santos  Isabel P. Ludka 《Earth, Moon, and Planets》2012,109(1-4):43-53

Varre-Sai, the most recent Brazilian meteorite fall, on June 19th, 2010 at Varre-Sai, in Rio de Janeiro State, Brazil (20°51??41??S; 41°44??.80??W). At least eight masses (total ~3.5?kg) were recovered. Most are totally covered by fusion crust. The exposed interior is of light-grey colour with a few dark shock veins. Five thin polished and etched sections were prepared from a slice weighing 35?g on deposit at the National Museum/UFRJ. It consists mostly of chondrules ranging in size from 0.35 to ~2.2?mm, and chondrule fragments enclosed in a crystalline matrix. The matrix consists of tiny isolated subhedral and anhedral crystals and opaque minerals that are intergrown with broken chondrules. The chondritic texture is poorly defined with chondrule textures that vary from non-porphyritic to porphyritic ones. The essential minerals are olivine (Fa_25±0.2) and low-Ca pyroxene (Fa_21.66±0.2Wo_1.4). Accessory minerals are plagioclase, apatite, Fe?CNi metal phases, troilite, chromite and magnetite. M?ssbauer spectroscopy analysis confirms that the mineral phases are olivine, pyroxene, troilite and kamacite/taenite. Chemical data indicate that Varre-Sai is a member of the low iron L chondrite group. The observed texture and mineral phases led us to classify Varre-Sai as an equilibrated petrologic type 5. The shock features of the minerals (undulatory extinction, planar structure and numerous cracks), as well as plagioclase partial or totally transformed to maskelynite, suggest a shock stage S4. Also, some post-impact metamorphic processes could be inferred from the meta-sulfide conjoint grains that show complex mixtures of kamacite?Ctaenite?Ctetrataenite and troilite. The occurrence of veins crosscutting the studied sections indicates that Varre-Sai was affected by a late fracturing event. Sealing of these fractures must have been a fast process, as shown by troilite globule textures pointing towards rapid solidification. The meteorite name was approved by the Nomenclature Committee of the Meteoritical Society (Meteoritic Bulletin, no 99).  相似文献   

Sedimentological/Palaeogeographic Data as Fundamental Building Blocks of the DDE Project:Critical Underpinning of Reconstructing Deep-time Earth Systems     

MONTA?EZ P. Isabel  HU Xiumian  HOU Mingcai  WANG Chengshan  CHEN Jitao  DDE Sedimentology  Palaeogeography Groups 《《地质学报》英文版》2019,93(Z1):52-54

正1 Introduction Sedimentary rocks archive important information for understanding how the earth system operates and how life and environments have evolved through earth history.Properly identifying characteristics of sedimentary rocks,along with the subsequent interpretation of depositional processes and sedimentary environments in a basin or locality,are fundamental to inter-basinal correlation of sedimentary successions as well as to understanding and deconvolving regional and global processes  相似文献   

A comparative analysis of time–depth relationships derived from scientific ocean drilling expeditions     

Sauermilch  Isabel  Mateo  Zenon Richard P.  Boaga  Jacopo 《Marine Geophysical Researches》2019,40(4):635-641

Marine Geophysical Research - Time–depth relationships (TDR) are required for correlating geological information from drill sites with seismic reflection profiles. Conventional...  相似文献