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1.
Abstract. New data on the planktonic diatoms from the Gulf of Naples are presented together with those from the literature. Information is given on abundances, seasonal cycles and distributions of 183 taxa, including species, varieties and forms. 相似文献
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Elizabeth Marino 《Global Environmental Change》2012,22(2):374-381
Migration decisions are complex and are linked to multiple vulnerabilities, including changing ecological conditions precipitated by climate change. As ecological thresholds are met, community-wide migrations will become more common. These community-wide migrations are more likely to occur to already vulnerable populations, and may levy high social costs. In order to prevent the negative outcomes associated with forced migration and diaspora, policy intervention is likely. Our research examines the case study of Shishmaref, Alaska, where relocation as an adaptation strategy to changing ecological conditions is the only sustainable option. We find that the colonial history in Shishmaref is explicitly linked to contemporary exposure to hazards and increased vulnerability. We further assess obstacles to a State sponsored relocation. These obstacles include disaster response protocol that does not adequately accommodate climate change scenarios. Relocation planning is further complicated by feelings of mis- and under-representation of local voices in political arenas. This case demonstrates the interrelatedness between historically constructed vulnerability and obstacles to adaptation planning. We also offer unique insight into the details of relocation planning as an adaptation strategy among one of the first community-wide migrations associated with climate change. 相似文献
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Summary Little comprehensive information has been reported on the behaviour of room-and-pillar mines. The objective of this paper is to present case data on mine failures in the Illinois basin for use in practice. Presented are results of an ongoing study and details on the site characteristics of cases where sags have developed on the surface. Site data are reported to show the geologic, mining, and sag conditions that existed. Sags mainly develop from pillar, floor, or pillar-floor failure. The character of the sags depends upon the type of mine failure as well as the overburden response.Preliminary results show that the statistical no-risk tributary pressure decreases over 300% as the mine age increases from about 2 to 100 years at a long-term value of approximately 300 psi (2070 kPa). As more information is collected and more analysis is done, the allowable tributary pressure can be determined for different site conditions.A plot is also reported that depicts the relationship of the maximum subsidence to site conditions. It was found that the modified subsidence factor was heavily dependent upon the overburden rock thickness. 相似文献
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Angela Marinoni Paolo Laj Pierre Alexandre Deveau Federica Marino Grazia Ghermandi Fabien Aulagnier Hlne Cachier 《Atmospheric Research》2005,74(1-4):565-580
The physical and chemical properties of aerosol particles were investigated at Plan d'Aups, one of the ESCOMPTE sites located in the St. Baume mountain area (700 m a.s.l.), 50 km east of Marseilles (France). The site is ideally located for assessing the vertical and horizontal extent of the pollution plume from the Marseilles–Berre area.Our study showed that polluted air masses from the Marseilles–Berre area are advected to Plan d'Aups in the early afternoon. Average daily concentration of particles reaches up to 40 μg m−3 while 1-h average particle number concentration is greater than 30,000 cm−3. Most of the particle mass is composed of SO42− and organic carbon (OC). The chemical properties of the particles revealed that an additional source, possibly from the industrial area of Gardanne, contributes to the aerosol mass. This last source is characterised by significant emissions of elements, such as Zn, V, Al and Si.In addition to transport, we found that gas-to-particle conversion takes place at the interface between the free troposphere and the boundary layer. We estimated that on average, 30% of the particle number is accounted for by direct nucleation. This is potentially a major aerosol source to the free troposphere. 相似文献
6.
M.A. Marino 《Journal of Hydrology》1973,19(1):43-52
Available expressions which describe the water-table fluctuation in a stream-aquifer system are based primarily on the assumption that the bed of the stream is as permeable as the aquifer it completely cuts through. Analytical expressions are developed, in terms of the head averaged over the depth of saturation, which take into account the semiperviousness of the streambed. The situations considered are finite and semi-infinite aquifer systems in which the water level in the semipervious stream is suddenly lowered below its initial elevation, and suddenly raised above its initial elevation, and maintained constant thereafter. As a by-product, solutions are also obtained for finite and semi-infinite aquifer systems in which the bed of the stream is as permeable as the aquifer. 相似文献
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Maria Bianca Cita Luca Capraro Neri Ciaranfi Enrico Di Stefano Fabrizio Lirer Patrizia Maiorano Maria Marino Isabella Raffi Domenico Rio Rodolfo Sprovieri Simona Stefanelli Gian Battista Vai 《《幕》》2008,31(4):408-419
The name Calabrian was introduced in the geological literature by the French stratigrapher Maurice Gignoux in 1910, and later described in his important monograph (633 pages) "Les formations marines pliocknes et quaternaires de l'ltalie du sud et de la Sicile "published in 1913. Detailed data were provided on several sections (Santa Maria di Catanzaro, Caraffa, Monasterace, Palermo) and on their fossil content. The Calabrian Stage has commonly been used for over fifty years as the oldest subdivision of the Qua- ternary, notably in the time scales of Berggren & van Cou- vering (1974) and Haq & Eysinga (1987). However, after the GSSP for the Pliocene/Pleistocene boundary (P/P) was approved by INQUA in 1982 and ratified by lUGS in 1984 at the Vrica section of Calabria, there was a decline in the usage of the stage name, and an increasing tendency by many Quaternary workers to question the boundary stratotype. This was because there was increasing evidence that it did not correspond to the beginning of the "ice age". In doing so, they were not complying with the recommendations presented at the 18th International Geological Congress (IGC) in London, 1948 (Oakley, 1950). 相似文献
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High connectivity and directional gene flow in European Atlantic and Mediterranean populations of Ciona intestinalis sp. A 下载免费PDF全文
Ornella Affinito Nikos Andreakis Luigi Caputi Rita Marino Raimondo Pannone Paolo Sordino Gabriele Procaccini 《Marine Ecology》2015,36(4):1230-1243
Understanding the factors that cause population divergence has long been of interest to marine biologists in their attempts to interpret the effect of human‐mediated vectors. Broadcast‐spawning species with limited dispersal capability are excellent candidates to measure the present‐day patterns of genetic diversity. The tunicate Ciona intestinalis (Ascidiacea) is comprised of a complex of morphologically cryptic species that form vigorous aggregates in eutrophic habitats (harbors, gulfs and lagoons) where they can compete with the epibenthic community and cause biofouling problems. This study investigated biogeographic variability and migration patterns of C. intestinalis sp. A along Northeast Atlantic and Mediterranean coasts using microsatellite markers. Data presented here on 371 specimens collected from 17 populations reveal high genetic polymorphism, but with a deficit of heterozygote deficiency. Absence of evidence for isolation by distance suggests that the genetic patterns do not reflect the geographic distribution of sampled populations. Substantial gene flow and artificial potential for dispersal boost high levels of within‐population genetic variability and prevent genetic differentiation within and between seas. A predominant eastward migration pattern was revealed by the data set, with very limited opportunity for C. intestinalis sp. A to travel westward. This directional movement indicates that other properties (e.g. habitat quality, genetic traits, mating system, life cycle) may cause adaptive divergence at a large biogeographic scale. 相似文献