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Monica Montefalcone Giancarlo Albertelli Carla Morri Valeriano Parravicini Carlo Nike Bianchi 《Marine pollution bulletin》2009,58(4):515-262
Using the Conservation Index, which measures the proportional amount of dead matte relative to live Posidonia oceanica, we assessed the health of 15 P. oceanica meadows at a regional scale along the coast of Liguria (NW Mediterranean). These areas were characterized by different degrees of anthropization, from highly urbanized sites to marine protected areas. Two different scenarios were identified according to depth: in shallow zones, the health of P. oceanica meadows was related to the degree of anthropization along the coastline. In contrast, in deep zones, most meadows exhibited poor health, independent of both the degree of disturbance and the legal measures protecting the area. Working synergistically with the regional impact of increased water turbidity, local impacts from the coast were recognized as the main causes of the severe regression of most Ligurian P. oceanica meadows. We conclude that marine protected areas alone are not sufficient to guarantee the protection of P. oceanica meadows. We emphasize the need for a management network involving the Sites of Community Interest (SCIs) containing P. oceanica meadows. 相似文献
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A. Rovere M. Vacchi V. Parravicini C. N. Bianchi N. Zouros M. Firpo 《Environmental Earth Sciences》2011,64(1):133-142
Within the definition given by UNESCO of World Cultural and Natural Heritage, geoheritage finds its significance both as the
geological or geomorphological elements of nature worthy of conservation and as habitat of threatened species of outstanding
universal value from the point of view of science or conservation. Definitions, methods, and applications for the conservation
and valorization of geoheritage have been proposed for various types of environments, but their application in underwater
areas is seldom, if even, reported. In this study, we propose a set of definitions and methods for the evaluation of scientific
and additional values in underwater environment, and we apply them in two Mediterranean areas: Sigri (Greece, Lesvos Island)
and Bergeggi (Italy, Liguria region). Results show the applicability of the schemes proposed in different geological and geomorphological
settings and provide tools for the evaluation of abiotic underwater heritage in the two areas. 相似文献
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Almeida Silva Karita de Souza Rolim Glauco Borges Valeriano Taynara Tuany da Silva Cabral de Moraes Jos Reinaldo 《Theoretical and Applied Climatology》2020,139(3):1019-1029
Theoretical and Applied Climatology - Coffee is the most consumed beverage and one of the most valuable commodities worldwide. The crop is very sensitive to meteorological elements, mainly at the... 相似文献
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M.C. Geraldes A.H. Paula J.M. Godoy C.M. Valeriano 《Journal of Geochemical Exploration》2006,88(1-3):384
Sediments from Guanabara Bay and two rivers were analyzed for Pb isotope composition. The results define linear groups interpreted as different sources of Pb. The samples from Iriri and Surui rivers present different Pb compositions probably resulting from two active pollutants which are transported in the waters to the Guanabara Bay, where they are mixed. The 206Pb/207Pb values of 1.151 and 1.091 presented here are in the range of Brazilian galena ore signature. 相似文献
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An abandoned estuary within Marajó Island: Implications for late Quaternary paleogeography of northern Brazil 总被引:1,自引:0,他引:1
Several previous studies have recognized paleochannels as the most typical geomorphologic features imprinted in the modern
landscape of Marajó Island, northern Brazil. A characterization of these paleochannels by detailed mapping has not yet been
accomplished, despite their great potential for helping reconstructing the succession of events responsible for the origin
and evolution of the drainage system at the mouth of the Amazon River during the Quaternary. The present study aims to provide
a detailed mapping and characterization of these paleochannels using remote sensing (i.e., SRTM, Landsat 5-TM, and Landsat
7-ETM+), integrated with sedimentological and radiocarbon data obtained from outcrops and cores. The mapped paleochannels
allowed for the first time correlation of the channel-like morphologies with fining-upward sedimentary successions, typical
of channel deposits. The study focuses on the Lake Arari area located in the northeast of Marajó Island, where a complex fluvial
network dominated by a funnel-shaped structure attributed to a Late Pleistocene paleoestuarine system was recognized. The
inner estuary was connected to three fluvial channels that ran from the east-southeast throughout an area currently occupied
by Marajó Bay, implying that this bay did not exist when the estuarine system was active. Separation of the eastern side of
Marajó Island due to tectonic causes related to capture of Tocantins River by northeastward-orientated faults would have interrupted
the fluvial inflow, ultimately causing the abandonment of the estuarine system. Today, the central part of the funnel-shaped
structure related to the Late Pleistocene paleoestuary is occupied by Lake Arari, where sediments started to accumulate no
earlier than the mid-Holocene. It is proposed that this lake might have developed from the Late Pleistocene estuary as the
fluvial inflow was cut off during the detachment of Marajó Island. Marajó Island serves as an example of a very dynamic site
of changing landscapes throughout the Quaternary as a result of tectonic activity. 相似文献
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M. Giudici F. Delay G. de Marsily G. Parravicini G. Ponzini A. Rosazza 《Stochastic Environmental Research and Risk Assessment (SERRA)》1998,12(3):191-204
The Differential System Method (DSM) permits identification of the physical parameters of finite-difference groundwater flow
models in a confined aquifer when piezometric head and source terms are known at each point of the finite-difference lattice
for at least two independent flow situations for which the hydraulic gradients are not parallel. Since piezometric head data
are usually few and sparse, interpolation of the measured data onto a regular grid can be performed with geostatistical techniques.
We apply kriging to the sparse data of a synthetic aquifer to evaluate the stability of the DSM with respect to uncorrelated
measurement errors and interpolation errors. The numerical results show that the DSM is stable. 相似文献
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Monica Montefalcone Valeriano ParraviciniMatteo Vacchi Giancarlo AlbertelliMarco Ferrari Carla MorriCarlo Nike Bianchi 《Estuarine, Coastal and Shelf Science》2010
Habitat fragmentation in meadows of Posidonia oceanica, the most important and abundant seagrass in the Mediterranean Sea, was investigated at a region-wide spatial scale using a synthetic ecological index, the Patchiness Index (PI). We tested the hypothesis that human impacts are the major factor responsible for habitat fragmentation in P. oceanica meadows contrasting fragmentation of meadows located in “anthropized” areas with that of meadows located in areas with low anthropization and considered as virtually “natural”. We also related fragmentation of meadow with the morphodynamic state of the submerged beach (i.e. distinctive types of beach produced by the topography, the wave climate and the sediment composition) in order to investigate the influence of one natural component on the seagrass meadow seascape. Results demonstrated that fragmentation in the P. oceanica meadows is strongly influenced by the human component, being lower in natural meadows than in anthropized ones, and that it is little influenced by the morphodynamic state of the coast. The use of landscape approaches to discriminate natural disturbance from human impacts that affect seagrass meadows is thus recommended for the proper management of coastal zones. 相似文献
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Miguel Tupinambá Monica Heilbron Claudio Valeriano Rubem Porto Júnior Fátima Blanco de Dios Nuno Machado Luiz Guilherme do Eirado Silva Júlio Cesar Horta de Almeida 《Gondwana Research》2012,21(2-3):422-438
The ca. 790–600 Ma Rio Negro Complex (RNC) of the Ribeira belt (Brazil) consists of a plutonic portion of a magmatic arc built by the E-vergent subduction of the ESE border of the São Francisco paleoplate during the amalgamation of Western Gondwana.The plutonic series comprises low- to medium-K granitoids (ca. 790–620 Ma) and high-K granitoids and shoshonite rocks (ca. 610–605). The age span of 185 m.y. is suggestive of a long history of arc-related magmatism, continuously or not in time. The Nd isotopic signatures of the RNC consist of εNd(t) ratios from ? 3 to + 5 for the medium-K series shoshonite series and from ? 14 to ? 3 for the younger high-K group. This time-dependent trend of Nd isotopes is indicative of progressive maturity of the arc over time. The same evolution is indicated by Sr data, as the medium-K rocks have 87Sr/86Sr initial ratios < 0.705 while the high-K rocks yield values between 0.705 and 0.710. The predominance of intermediate rocks over mafic ones suggests an initial intra-oceanic to transitional stage, possibly developed in a distal portion of a passive margin, such as the Japanese arc, evolving to a more developed, differentiated felsic rock associations.The role of transform fault zones, such as the Luanda shear zone, is emphasized in order to explain the consumption of a wide oceanic plate in the inner portion of Western Gondwana. 相似文献