Heavy Metal Accumulation in the Lichen Evernia prunastri Transplanted at Urban, Rural and Industrial Sites in Central Italy     

Marcelo Enrique Conti  Mabel Tudino  Jorge Stripeikis  Gaetano Cecchetti 《Journal of Atmospheric Chemistry》2004,49(1-3):83-94

The lichen Evernia prunastri has been employed for biomonitoring the atmospheric deposition of heavy metals at urban, rural and industrial sites in Central Italy. Lichen samples have been collected in a control site 1500 m a. s. l. (Parco Nazionale dAbruzzo, Central Italy) and subsequently transplanted at urban site (Cassino city center), at rural location 7 km away from Cassino (S. Elia Fiumerapido) and at industrial location (Piedimonte S. Germano) surrounding an automobile factory. Once defined the surface of impact relevant to this work, the lichen samples were transplanted at the four cardinal points of each site. Studies of bioaccumulation of Pb, Cd, Cr, Cu and Zn in lichen samples were performed five times at regular intervals between November 2000–December 2001. Microwave digestion of the samples and graphite furnace atomic absorption spectrometry were employed for the heavy metal determinations. Suitable certified reference materials (CRM) were used for validation of the analytical methodology. Results showed the ability of Evernia prunastri to accumulate the heavy metals under study. As expected, the area chosen as control site showed significantly (Friedman test, cluster analysis) lower impact in comparison to the other sites and the rural site showed smaller impact than the urban and the industrial sites.  相似文献   

Convection in a rotating deep compressible spherical shell: Application to the Sun     

Gaetano Belvedere  Lucio Paternò 《Solar physics》1977,54(2):289-312

In this paper we study the interaction of rotation with convection in a deep compressible spherical shell as the Sun's convection zone. We examine how the energy transport and the large scale motions can be affected by rotation. In particular we study how a large scale meridional circulation can give rise to variations of angular velocity with latitude and depth.It is assumed that the energy transport is only due to convection and that the mixing-length theory gives an adequate representation of it. Furthermore we assume that rotation acts as a perturbation of the turbulent convective flux through its transport coefficient.The equations involved in the model are integrated numerically in the limit of large viscosity and slow rotation. After having expanded all physical quantities to the first order in terms of Legendre polynomials, the fitting with the observed solar differential rotation gives the expansion parameter, which represents the coupling constant between rotation and convection.The results show a three-cell circulation extending from the poles to the equator. The first one is located in the lower half of the convection zone with the fluid rising at the equator and sinking at the poles. In the second one the direction of the motion is reversed while the third one, located in a thin upper layer, shows the same characteristics of the first one. The meridional velocities at the surface are directed towards the poles and are about 20 cm s^-1. In the other cells the meridional velocities are typically of a few cm s^-1 while the radial velocities are of the order of a few tenths of cm s^-1.The heat flux relative variation at the surface is about 10^-4 (3 × 10^-3 at the bottom) with a polar excess. The temperature variation at the surface is of the same order, with an equatorial excess however. The convection seems to be stabilized stronger at the equator. The angular velocity increases inwards and varies about 6% between the surface and the bottom of the convection zone.An attempt is made for explaining the picture which emerges. In particular the negligible flux and temperature variations at the surface are explained in terms of equalization by the particular structure of the latitudinal flow. This configuration of large scale circulation is attributed to the high stratification of the convection zone with depth.  相似文献   

Expected loss‐based alarm threshold set for earthquake early warning systems Earthquake Engng Struct. Dyn. 2007 (DOI: 10.1002/eqe.675)     

Iunio Iervolino  Massimiliano Giorgio  Gaetano Manfredi 《地震工程与结构动力学》2007,36(9):I-I

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Reply to comments by Henry N. Pollack and David S. Chapman on “Spherical harmonic analysis of Earth’s conductive heat flow”     

V. M. Hamza  R. R. Cardoso  C. F. Ponte Neto 《International Journal of Earth Sciences》2008,97(2):233-239

Pollack and Chapman, hereafter referred to as P&C, argue that: (1) errors arising from lack of quality control in the IHFC database are not important and not properly documented, (2) resolution of spatial patterns in global heat flux distribution should not be represented by spherical harmonics and (3) heat flow in young oceanic crust and global heat loss are better represented by a contested 1-D cooling model than by the data. We disagree and provide additional information that may help clear up such misunderstandings. We also mention briefly the results of a new improved thermal model of the lithosphere that satisfactorily reproduces the main features identified in observational data sets of heat flow and ocean floor bathymetry. Thus, there is no reason to invoke the ad hoc hypothesis of large-scale hydrothermal circulation in the ocean crust.  相似文献   

The stability of UO2OH+ and UO2[HPO4]22− complexes at 25°C (reply to a comment by V. S. Tripathi)     

Donald Langmuir  Gaetano Dongarra 《Geochimica et cosmochimica acta》1982,46(10):2005

Tripathi argues that we could not determine the stability constant (β₂) of UO₂[HPO₄]₂^2? in our solutions because they were supersaturated with respect to solid uranyl triphosphate. This is irrelevant because no phosphate solids were present in solution during our experiments. He further argues that the conditions of our experiments were not ideal for us to determine the potentially most accurate value of β₂. This is also irrelevant. The point is that our published value of log β₂ = 18.3 ± 0.2 is given with an uncertainty which clearly acknowledges the inaccuracy of its determination based on our experimental and computational approach.  相似文献   

Phylogeographic study on the chub mackerel (Scomber japonicus) in the Northwestern Pacific indicates the late Pleistocene population isolation          下载免费PDF全文

Shuai Yan  Gaetano Catanese  Christopher L. Brown  Ming Wang  Chaopin Yang  Tingbao Yang 《Marine Ecology》2015,36(3):753-765

In the present study, the population genetic structure and historical demography of the chub mackerel, Scomber japonicus, in the Northwestern Pacific were examined based on the full‐length sequences of the mitochondrial control region and cytochrome b gene. A total of 320 individuals was sampled from 11 localities along the coast of China and Japan from August 2011 to May 2013. Two main clades representing Chinese and Japanese populations, respectively, were detected, suggesting population isolation of S. japonicus during the late Pleistocene era. The Chinese clade was further divided into two small clades and the distribution of haplotypes were not related to sampling locality, which may be a signature of secondary contact following past division. Analyses of molecular variance and pairwise F_ST revealed significant genetic differentiation between the Chinese and Japanese populations, but a lack of genetic structure for the populations along the coast of China. Both neutrality tests and mismatch distribution analysis suggested that the populations along the coast of China experienced population expansion during the late Pleistocene. Historical events, biological characteristics and other extrinsic forces such as ocean currents may all be associated with the current phylogeographic pattern of S. japonicus in the Northwestern Pacific.  相似文献   

Probabilistic GIS-based method for delineation of urban flooding risk hotspots   总被引：3，自引：1，他引：2  

Fatemeh Jalayer  Raffaele De Risi  Francesco De Paola  Maurizio Giugni  Gaetano Manfredi  Paolo Gasparini  Maria Elena Topa  Nebyou Yonas  Kumelachew Yeshitela  Alemu Nebebe  Gina Cavan  Sarah Lindley  Andreas Printz  Florian Renner 《Natural Hazards》2014,73(2):975-1001

Identifying urban flooding risk hotspots is one of the first steps in an integrated methodology for urban flood risk assessment and mitigation. This work employs three GIS-based frameworks for identifying urban flooding risk hotspots for residential buildings and urban corridors. This is done by overlaying a map of potentially flood-prone areas [estimated through the topographic wetness index (TWI)], a map of residential areas and urban corridors [extracted from a city-wide assessment of urban morphology types (UMT)], and a geo-spatial census dataset. A maximum likelihood method (MLE) is employed for estimating the threshold used for identifying the flood-prone areas (the TWI threshold) based on the inundation profiles calculated for various return periods within a given spatial window. Furthermore, Bayesian parameter estimation is employed in order to estimate the TWI threshold based on inundation profiles calculated for more than one spatial window. For different statistics of the TWI threshold (e.g. MLE estimate, 16th percentile, 50th percentile), the map of the potentially flood-prone areas is overlaid with the map of urban morphology units, identified as residential and urban corridors, in order to delineate the urban hotspots for both UMT. Moreover, information related to population density is integrated by overlaying geo-spatial census datasets in order to estimate the number of people affected by flooding. Differences in exposure characteristics have been assessed for a range of different residential types. As a demonstration, urban flooding risk hotspots are delineated for different percentiles of the TWI value for the city of Addis Ababa, Ethiopia.  相似文献