Evaluation of the applicability of a fuzzy index of ecosystem integrity (FINE) to characterize the status of Tyrrhenian lagoons     

Munari C  Mistri M 《Marine environmental research》2007,64(5):629-638

The new index FINE, a multimetric, fuzzy-based index for the evaluation of environmental quality for Mediterranean transitional waters, was calculated using biotic data gathered between 2000 and 2006 at 15 stations in 4 Tyrrhenian transitional water ecosystems (Orbetello Lagoon, Padrongiano Delta, Stagno di S. Teodoro, and Stagno di Tortolì), i.e. in a different biogeographic sub-province respect to the one in which the index was developed and validated. The rationale of FINE is that certain attributes, selected on the basis of established principles of benthic ecology, are fundamental for lagoon ecosystem function. A set of other indices (Simpson's 1-lambda', the W-statistics, AMBI, and BOPA) was also calculated and compared to FINE outputs. FINE, 1-lambda', and the W-statistics were significantly correlated with sedimentary organic matter content. Some stations were unequivocally assigned to the same ecological status, independently from the index used; for others, some discrepancies were evident. Mediterranean transitional waters probably share ecosystem complexities which are not yet fully captured by indices developed and validated elsewhere.  相似文献   

A two-color CCD survey of the North Celestial Cap: I. The method     

Evgeny Gorbikov  Noah Brosch  Cristina Afonso 《Astrophysics and Space Science》2010,326(2):203-217

We describe technical aspects of an astrometric and photometric survey of the North Celestial Cap (NCC), from the Pole (δ=90°) to δ=80°, in support of the TAUVEX mission. This region, at galactic latitudes from ∼17° to ∼37°, has poor coverage in modern CCD-based surveys. The observations are performed with the Wise Observatory one-meter reflector and with a new mosaic CCD camera (LAIWO) that images in the Johnson–Cousins R and I bands a one-square-degree field with sub-arcsec pixels. The images are treated using IRAF and SExtractor to produce a final catalogue of sources. The astrometry, based on the USNO-A2.0 catalogue, is good to ∼1 arcsec and the photometry is good to ∼0.1 mag for point sources brighter than R=20.0 or I=19.1 mag. The limiting magnitudes of the survey, defined at photometric errors smaller than 0.15 mag, are 20.6 mag (R) and 19.6 (I). We separate stars from non-stellar objects based on the object shapes in the R and I bands, attempting to reproduce the SDSS star/galaxy dichotomy. The completeness test indicates that the catalogue is complete to the limiting magnitudes.  相似文献   

Technological study of “ghiara” mortars from the historical city centre of Catania (Eastern Sicily, Italy) and petro-chemical characterisation of raw materials     

Cristina M. Belfiore  Mauro F. La Russa  Paolo Mazzoleni  Antonino Pezzino  Marco Viccaro 《Environmental Earth Sciences》2010,61(5):995-1003

This paper presents new petro-chemical data on some typical mortars found in many buildings in the historic city centre of Catania (Eastern Sicily). Extensively used in the architecture of the city from the second half of the nineteenth century until the mid-twentieth century, these mortars are characterised by a particular aggregate locally known as “agghiara” or “ghiara”. This is the product of thermal transformation induced by the heating undergone by palaeo-soils, originally rich in organic matter, covered by lava flows, which change their colour to reddish nuances. The volcanic origin of ghiara is a peculiar feature of the Etnean area. Mixed with lime, it gives to mortars an intense reddish colour, as well as hydraulic properties, which are comparable with those of the historically used pozzolana. This work aimed at complete characterisation of these ghiara mortars, for providing information on several important technological aspects. In order to get information on used raw materials, sampling of some ancient underground quarries, located both in the historic city centre and at the periphery, was also performed. Results led to the complete characterisation of the selected ghiara mortars and yielded information on some technological features and the composition of both newly formed and secondary phases, these latter due to alteration processes. The hydraulic properties of mortars have been related to the occurrence of amorphous phases within the ghiara aggregate, which were identified by means of SEM morphological observations. These phases, formed during the “firing” process of palaeo-soils, react with lime producing hydraulic compounds (C–S–H and C–A–H), which are responsible for the mortars durability.  相似文献   

Influence of sample and terrain unit on landslide susceptibility assessment at La Pobla de Lillet,Eastern Pyrenees,Spain   总被引：2，自引：2，他引：0  

Cristina Baeza  N. Lantada  J. Moya 《Environmental Earth Sciences》2010,60(1):155-167

The reliability of susceptibility maps depends largely on the quality of the information used for its evaluation. This study seeks to analyze the influence of sample size and type on the results of discriminant analysis applied to shallow landslide susceptibility assessment. The study also assesses the role of the terrain unit in discriminant analysis. To this end, two databases based on fieldwork (slope unit) and GIS with 15- and 45-m grid cells (grid cell-based unit), were compared in the same zone at La Pobla de Lillet, Spanish Eastern Pyrenees. The results show that although there is no significant influence of the type of sample, it is necessary to use at least half of the individuals of the sample in order to obtain good results from discriminant analysis. It is the terrain unit that exerts the biggest influence on the result of susceptibility. Some morphometric parameters related to landslides were compared in the databases. The slope unit of the fieldwork database better reflects the land characteristics than the regular grid used by GIS. The values of the variables obtained by GIS procedures are smooth, obtaining mean errors for the slope angle variable of 19.5 and 33.5% for the grids of 15 and 45 m, respectively, in the study area. One-way and T tests demonstrate that the smoothness of the values exerts a decisive influence on the discriminant results. Kappa’s analysis shows that there is no significant equivalence between some of the categorical variables used in both databases. The use of these variables demand the application of clearly defined criteria. The cell size should match the dimensions of the phenomenon analyzed given the unsuitability of the grid of 45 m in this study.  相似文献   

Butyltin compounds,sterility and imposex assessment in Nassarius reticulatus (Linnaeus, 1758), prior to the 2008 European ban on TBT antifouling paints,within Basque ports and along coastal areas     

J. Germán Rodríguez  Itziar Tueros  Ángel Borja  Javier Franco  J. Ignacio García Alonso  Joxe Mikel Garmendia  Iñigo Muxika  Cristina Sariego  Victoriano Valencia 《Continental Shelf Research》2009,29(8):1165-1173

Levels of imposex (superimposition of male characters, upon females) and the presence of sterile females are assessed in the gastropod Nassarius reticulatus (L.), at 35 locations in the Basque Country. At 18 of these localities, organotin bioaccumulation (tributyltin (TBT); dibutyltin; monobutyltin) was evaluated, using isotope dilution GC–ICP–MS. Higher imposex levels and TBT body burden were found in confined harbours, with large vessel traffic or the presence of an offshore fleet. The highest values were found for the port of Pasaia, near to a shipyard (a relative penis size index of up to 92%, and TBT body burden up to 405 ng g^?1 – given on a dry weight basis as Sn). Imposex effects were evaluated also in parasitized females, at some of the sampling sites. The percentage of presence of c-type Vas Deferens sequence stages (i.e., with vas deferens beginning at the oviduct opening) was higher in parasitized females. In turn, there was an absence of highly convoluted oviduct in parasitized females.  相似文献   

The composition and conservation of Romania's plant cover     

E. Cristina Muica  Ana Popova-Cucu 《GeoJournal》1993,29(1):9-18

Romania is characterised by great floristic diversity and there are many distinctive aspects to the distribution of vegetation units. However, even the sparsely-populated mountainous country has been affected by anthropic activity, increasing in intensity through the expansion of agriculture during the nineteenth century and the recent emphasis on industrial development. It is therefore essential that the diverse plant cover should be given the protection of national park or nature reserve status. The present designations are substantial, though not yet adequate, and careful monitoring is needed to establish the extent or further provision.  相似文献   

Total oxyradical scavenging capacity responses in Mytilus galloprovincialis transplanted into the Venice lagoon (Italy) to measure the biological impact of anthropogenic activities     

Camus L  Pampanin DM  Volpato E  Delaney E  Sanni S  Nasci C 《Marine pollution bulletin》2004,49(9-10):801-808

Oxidative stress related investigations to monitor the impact of the pollutant discharges into the Venice lagoon (Italy) originating from anthropogenic activities (raw sewage water, agricultural and industrial effluents, oil tanker traffic), on marine organisms have classically been carried out by analyzing specific, single antioxidants (i.e. catalase, superoxide dismutase). In this paper, two studies are reported where the total oxyradical scavenging capacity assay (TOSC) was selected and measured toward peroxyl, and hydroxyl free radicals, and peroxynitrite in mussels (Mytilus galloprovincialis) transplanted into the Venice city and throughout the lagoon to measure the biological effects of anthropogenic activities. In the first experiment, mussels from a clean site (farm) were transplanted to the urban area of Venice for 0, 1, 2 and 4 weeks; cytosolic TOSC toward peroxyl and hydroxyl free radicals, and peroxynitrite revealed that the transplantation process caused a stress (handling stress, anoxia, oxidative burst) resulting in a reduction of TOSC in both control and urban sites, therefore, preventing clear interpretation of the data after one week. At week 2, a significant TOSC reduction (P < 0.05) toward peroxyl and hydroxyl radicals in the urban site revealed that mussels experienced oxidative pressure exerted by pollutants. Most TOSC values returned to initial levels at week 4; however, TOSC induction was noticed in the control group toward peroxyl and hydroxyl radicals while in the exposed group it was not indicating an inhibition of the oxidative metabolism. In the second experiment, mussels were deployed at seven different sites throughout the lagoon. After five weeks of exposure, significant TOSC reduction was measured (P < 0.05) toward peroxyl for Palude della Rosa, Chioggia and Valle Millecampi, toward hydroxyl radicals for Valle Millecampi and Campalto and toward peroxynitrite for Valle Millecampi. Although these data indicate a depletion of the low molecular weight scavengers, additional biomarkers are needed to draw a conclusion on the health of the mussels. TOSC was proved to be an interesting health index parameter to measure pollution impact in a transplantation study provided that the mussels are exposed for two weeks and a control is run in parallel.  相似文献   

Principal Component Analysis of the Solar Magnetic Field I: The Axisymmetric Field at the Photosphere     

John?K.?LawrenceEmail author  Ana?Cristina?Cadavid  Alexander?Ruzmaikin 《Solar physics》2004,225(1):1-19

A principal component analysis, or proper orthogonal decomposition, of the axisymmetric magnetic field at the photosphere is carried out to find an optimal representation of the observed solar cycle. The 22-year periodic field requires just two modes. NSO Kitt Peak synoptic maps for Carrington rotations 1664–2007 were reduced by taking both the mean and the median field over longitude to produce two sequences of functions of sine latitude spanning 25.7 years. The lowest modes of each are determined by the polar fields. The mean field is most efficient at representing the periodic field, but the median field is more efficient at representing the evolution of the diffuse field patterns.  相似文献   

The use of a non-lethal tool for evaluating toxicological hazard of organochlorine contaminants in Mediterranean cetaceans: new data 10 years after the first paper published in MPB     

Fossi MC  Marsili L  Neri G  Natoli A  Politi E  Panigada S 《Marine pollution bulletin》2003,46(8):972-982

In the Mediterranean Sea, top predators, and particularly cetacean odontocetes, accumulate high concentrations of organochlorine contaminants and toxic metals, incurring high toxicological risk. In this paper we investigate the use of the skin biopsies as a non-lethal tool for evaluating toxicological hazard of organochlorines in Mediterranean cetaceans, presenting new data 10 years after the paper published by Fossi and co-workers [Mar. Poll. Bull. 24 (9) (1992) 459] in which this new methodology was first presented. Some organochlorine compounds, now with worldwide distribution, are known as endocrine disrupting chemicals (EDCs). Here the unexplored hypothesis that Mediterranean cetaceans are potentially at risk due to organochlorines with endocrine disrupting capacity is investigated. High concentrations of DDT metabolites and PCB congeners (known as EDCs) were found in the different Mediterranean species (Stenella coeruleoalba, Delphinus delphis, Tursiops truncatus and Balaenoptera physalus). In this paper we also propose benzo(a)pyrene monooxygenase (BPMO) activity in marine mammal skin biopsies (non-lethal biomarker) as a potential indicator of exposure to organochlorines, with special reference to the compounds with endocrine disrupting capacity. A statistically significant correlation was found between BPMO activity and organochlorine levels (DDTs, pp(')DDT, op(')DDT, PCBs and PCB99) in skin biopsies of males of B. physalus. Moreover a statistical correlation was also found between BPMO activity and DDT levels in skin biopsies of the endangered Mediterranean population of D. delphis. These results suggest that BPMO induction may be an early sign of exposure to organochlorine EDCs and can be used for periodic monitoring of Mediterranean marine mammal toxicological status.  相似文献   

7th Latin-American Conference on Space Geophysics, Atibaia, SP, Brazil, March 29–April 2, 2004     

Barclay Clemesha  Chairman&#x;Colage Editorial Committee  Cristina Mandrini  Paulo Batista  Inez Batista  Abraham Chian  Co-editors 《Journal of Atmospheric and Solar》2005,67(17-18)

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