Spatial trends in heavy metals and nitrogen deposition in Navarra (Northern Spain) based on moss analysis     

L. González-Miqueo  D. Elustondo  E. Lasheras  R. Bermejo  J. M. Santamaría 《Journal of Atmospheric Chemistry》2009,62(1):59-72

A biomonitoring survey using the moss species Hypnum cupressiforme Hedw. was performed in the North of Navarra (Spain) in 2006. The levels of V, Cr, Mn, Ni, Cu, Zn, As, Zr, Cd, Hg and Pb, and the total nitrogen content were determined in the samples by means of ICP-MS, CV-AA, and the Kjeldahl method. PCA analysis showed a differentiation between lithogenic (V, Cr, Mn, Ni, As and Zr) and anthropogenic elements (Mn, Cu, Zn, Cd, Hg and Pb). Spatial distribution maps were drawn using the kriging method, in order to identify the most affected areas and the main pollution sources. A similar spatial distribution was observed for the elements belonging to each group separated by the PCA, showing an important contribution from metal industries located in the Basque Country, as well as influence of long-range transboundary pollution processes. Background levels were also determined for the study area, along with the contamination factor for the different elements analysed. Mosses seemed to be good biomonitors of N deposition in areas of accumulation.  相似文献   

Effect of growth on active biomonitoring with terrestrial mosses     

J. Angel Fernández  Angela Ares  Ana Rey-Asensio  Alejo Carballeira  Jesus R. Aboal 《Journal of Atmospheric Chemistry》2009,63(1):1-11

The effects of growth of autoirrigated, shaded transplants of Pseudoscleropodium purum on the quantification of tissue concentrations of Cd, Cu, Hg, V and Zn, were investigated in 4 exposure periods, each of 56 days, at 7 sampling sites (contaminated and uncontaminated). Concentrations of the elements in the basal portions of the moss shoots were compared with the concentrations in the portions of the shoots that grew during the exposure period. Mercury and V were present at lower concentrations in the new portions of the shoots than in the basal portions, whereas the opposite was true for Cd, Cu and Zn. The magnitude of error introduced by growth was not negligible, and in some cases was higher than 40%, relative to the results obtained by analysis of the whole shoot. Devitalization of moss prior to its use as transplant material is recommended to avoid growth of the plant during the exposure period.  相似文献   

Applying size segregation to relate the surrounding aerosol pollution to its source   总被引：1，自引：0，他引：1  

Irena Grgić  Janja Turšič  Axel Berner 《Journal of Atmospheric Chemistry》2009,63(3):247-257

Size segregated sampling of aerosol particles at the coal-fired power station Šoštanj, Slovenia was performed by a newly developed system. In addition, simultaneous sampling of particles was performed at two locations, Velenje and Veliki vrh, chosen on the basis of long term monitoring of SO₂ in the influential area of power plant. The signature of the power plant (e.g. characteristic size distributions of some typical trace elements) was identified. For elements, like As, Mo, Cd and Ga, which are typical for coal combustion, the highest concentrations were observed in the size range between 1 and 4 μm. For Se and sometimes for Ga two modes were identified, first between 0.1 and 0.5 μm and second between 1 and 4 μm. Ratios between the average concentrations of selected elements in fine and coarse particles collected at Veliki vrh (the most influenced location) and Velenje (usually not influenced by the thermo power station) were significantly higher than 1 in the case of Mo and Se for coarse and fine size range, while for As the ratio was higher than 1 for the coarse fraction. Consequently, Mo, Se and As were found as the most important tracers for the emissions from the investigated source. On the basis of the ratios between the concentrations of elements measured in particles at low and high SO₂ concentrations at Veliki vrh, Cd was shown to be a typical tracer as well. Our results definitely showed that size segregated measurements of particles at the source and in the influenced area give more precise information on the influence of source to the surrounding region. It was found that patterns of size distributions for typical trace elements observed at the source are found also in the influenced area, i.e. Veliki vrh.  相似文献   

HIDDRA: a highly independent data distribution and retrieval architecture for space observation missions     

Daniel Higuero  Juan M. Tirado  Jesús Carretero  Fernando Félix  Antonio de la Fuente 《Astrophysics and Space Science》2009,321(3-4):169-175

Institutions such as NASA, ESA or JAXA find solutions to distribute data from their missions to the scientific community, and their long term archives. This is a complex problem, as it includes a vast amount of data, several geographically distributed archives, heterogeneous architectures with heterogeneous networks, and users spread around the world. We propose a novel architecture that solves this problem aiming to fulfill the requirements of the final user. Our architecture is a modular system that provides a highly efficient parallel multiprotocol download engine, using a publisher/subscriber policy which helps the final user to obtain data of interest transparently. We have evaluated a first prototype, in collaboration with the ESAC centre in Villafranca del Castillo (Spain) that shows a high scalability and performance, opening a wide spectrum of opportunities.  相似文献   

Classification of BeppoSAX’s gamma-ray bursts     

István Horváth 《Astrophysics and Space Science》2009,323(1):83-86

The BeppoSAX Catalog has been very recently published. In this paper we analyze—using the Maximum Likelihood (ML) method—the duration distribution of the 1003 GRBs listed in the catalog with duration. The ML method can identify the long and the intermediate duration groups. The short population of the bursts is identified only at a 96% significance level. MC simulation has been also applied and gives a similar significance level; 95%. However, the existence of the short bursts is not a scientific question after the Compton Gamma-Ray Observatory’s observation. Our minor result is this well-known fact that in the BeppoSAX data the short bursts are under-represented, mainly caused by the different triggering system. Our major result is the identification of the intermediate group in the BeppoSAX data. Therefore, four different satellites (CGRO, Swift, RHESSI and BeppoSAX) observed the intermediate type Gamma-Ray Burst.  相似文献   

Integral-field high spatial resolution spectroscopy of the giant Hii region NGC5461     

Jesús López H.  Fabio Bresolin  Elena Terlevich  Roberto Terlevich  Daniel Rosa-González 《Astrophysics and Space Science》2009,324(2-4):351-354

We present preliminary results obtained from integral-field (IFU) data of the giant extragalactic Hii region NGC5461, located in a spiral arm (RA=14^h03^m41.4^s, dec=+54°19′05″) of M101. The spatial and spectral information obtained with IFUs allows us to decompose the Hii region and analyze it at high resolution.  相似文献   

Gas kinematics in the halo of the warm ULIRG PKS1345+12     

Javier Rodríguez Zaurín  Joanna Holt  Clive N. Tadhunter  Rosa M. González Delgado 《Astrophysics and Space Science》2009,324(2-4):225-229

We use long-slit spectra taken with the William Herschel Telescope on La Palma and high-resolution Hubble Space Telescope imaging to study the gas kinematic in the halo of the ultraluminous infrared/radio galaxy PKS1345+12 (z=0.122). Our long-slit spectra show line splitting at the locations of massive star clusters ( $10^{6}<M_{\mathrm{SSC}}^{\mathrm{YSP}}<10^{7}$ M_⊙), indicating that they are moving at up to 450 km?s^?1 with respect to the local ambient gas. Given their kinematics, it is plausible that these super star clusters have been formed either in fast-moving gas streams or tidal tails that are falling back into the nuclear regions as part of the merger process, or as a consequence of jet-induced star formation linked to the extended, diffuse radio emission detected in the halo of the galaxy.  相似文献   

Preface     

Enrique Pérez  Richard de Grijs  Rosa M. González Delgado 《Astrophysics and Space Science》2009,324(2-4):79-81

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Initial mass function biases created by binning and unresolved systems     

Jesús Maíz Apellániz 《Astrophysics and Space Science》2009,324(2-4):95-100

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Star-formation modes in the solar neighborhood     

Emilio J. Alfaro  Federico Elias  Jesús Cabrera-Caño 《Astrophysics and Space Science》2009,324(2-4):141-146

We perform a study into the spatial and kinematical distribution of young open clusters in the solar neighborhood, distinguishing between Gould Belt and local Galactic disk members. We use a previous estimate of the structural parameters of both systems obtained from a sample of O to B6 stars from Hipparcos. The two star-forming regions that dominate and give the Gould Belt its characteristic inclined shape show a striking difference in their content of star clusters: while Ori OB1 is richly populated by open clusters, not a single one can be found within the boundaries of Sco OB2. This is mirrored in velocity space, translating again into an abundance of clusters in the region of the kinematic space populated by the members of Ori OB1, and a marginal number of them associated with Sco OB2. We interpret all these differences by characterizing the Orion region as a cluster complex typically surrounded by a stellar halo, and the Sco-Cen region as an OB association in the outskirts of the complex. The different contents of star clusters, the different heights above the Galactic plane and the different residual velocities of Ori OB1 and Sco OB2 can be explained in terms of their relative position with respect to the density maximum of the Local Arm in the solar neighborhood. The origin of this feature could have been the interaction of a density wave with the local interstellar medium close to the Galactic co-rotation radius.  相似文献