Modelling seasonal variations of natural radioactivity in soils: A case study in southern Italy     

Ilaria Guagliardi  Natalia Rovella  Carmine Apollaro  Andrea Bloise  Rosanna De Rosa  Fabio Scarciglia  Gabriele Buttafuoco 《Journal of Earth System Science》2016,125(8):1569-1578

The activity of natural radionuclides in soil has become an environmental concern for local public and national authorities because of the harmful effects of radiation exposure on human health. In this context, modelling and mapping the activity of natural radionuclides in soil is an important research topic. The study was aimed to model, in a spatial sense, the soil radioactivity in an urban and peri-urban soils area in southern Italy to analyse the seasonal influence on soil radioactivity. Measures of gamma radiation naturally emitted through the decay of radioactive isotopes (potassium, uranium and thorium) were analysed using a geostatistical approach to map the spatial distribution of soil radioactivity. The activity of three radionuclides was measured at 181 locations using a high-resolution ?-ray spectrometry. To take into account the influence of season, the measurements were carried out in summer and in winter. Activity data were analysed by using a geostatistical approach and zones of relatively high or low radioactivity were delineated. Among the main processes which influence natural radioactivity such as geology, geochemical, pedological, and ecological processes, results of this study showed a prominent control of radio-emission measurements by seasonal changes. Low natural radioactivity levels were measured in December associated with winter weather and moist soil conditions (due to high rainfall and low temperature), and higher activity values in July, when the soil was dry and no precipitations occurred.  相似文献   

Food preferences and rhythms of feeding activity of two co‐existing demersal fish,the longspine snipefish,Macroramphosus scolopax (Linnaeus, 1758), and the boarfish Capros aper (Linnaeus, 1758), on the Mediterranean deep shelf          下载免费PDF全文

Paolo Carpentieri  Natalia Serpetti  Francesco Colloca  Alessandro Criscoli  Giandomenico Ardizzone 《Marine Ecology》2016,37(1):106-118

The feeding behaviour of two potentially competing species, the longspine snipefish, Macroramphosus scolopax, and the boarfish Capros aper was examined. While both species are very abundant along the Mediterranean coast and are regularly caught by demersal trawlers, they are of no commercial value. The diets of boarfish and longspine snipefish were investigated from samples collected between January 2001 and May 2002. Variations in the diet with fish size and season, as well as diet overlap and diversity were explored. Mysid shrimps, amphipods and gastropods were the most important food items in the diet of longspine snipefish. During ontogenetic development, M. scolopax occupies different trophic levels: the diet shifts from being predominantly composed of mysids (Anchialina agilis, Lophogaster typicus, Erythrops sp., Leptomysis spp.) in the smaller longspine snipefish [<6.5 cm total length (TL)] towards decapods (Anapagurus laevis) and amphipods (Leucothoe incisa, Eusirus longipes, Hyperidea) in the larger individuals (>6.5 cm TL). Crustacean decapods and copepods were the most important prey in the stomachs of boarfish. Mysids (Lo. typicus), euphausiids and nematodes were present in the larger individuals (>8 cm TL). A more generalist diet, still containing copepods, crustacean decapods, gastropods (Limacina retroversa) and a large variety of amphipods (e.g. Phtysica marina, Stenotoe bosphorana) and mysids (e.g. A. agilis, Leptomysis spp., Erythrops sp.), dominated the diet of C. aper between 2 and 8 cm TL. Diet overlap between longspine snipefish and boarfish was very low and the differences in stomach species diversity were explained by season and fish size.  相似文献   

The lithological–geochemical characteristics for the Permian oil-and-gas bearing complex of the Lena-Anabar trough (based on the example of Ust’-Olenekskaya well no. 2370)     

E. A. Bakay  M. E. Smirnova  N. I. Korobova  D. V. Nadezhkin 《Moscow University Geology Bulletin》2016,71(2):181-193

Lithofacies of different geneses are identified in a section of Permian deposits based on the study of the core material; the best reservoirs in the Permian complex of the Lena-Anabar trough are related to the sand bodies of the delta system. The Permian oil-source strata, where organic matter was accumulated under marine conditions, are recognized, the initial characteristics of organic matter are estimated, and the initial high oil-generation potential is substantiated. The results of the lithological–geochemical studies of the samples from one of the northernmost wells in the Laptev Sea coast have been published for the first time.  相似文献   

Intensification of Biological Afterpurification of Municipal Wastewater by Some Pleistophyte Species     

Smirnova  L. L.  Mironova  N. V. 《Water Resources》2004,31(4):470-473

The use of semiaquatic plants (Pistia stratiotes and frogbit) for afterpurification of domestic wastewater is shown to improve water quality. Planting pleistophytes in watercourses and biological ponds, into which pretreated wastewater is discharged, is especially efficient in summer and autumn, when the load on treatment facilities increases.  相似文献   

Characterization of natural hydrocarbon seepage in the South Caspian Sea off Iran using satellite SAR and geological data     

Andrei Yu. Ivanov  Hadi Gerivani  Natalia V. Evtushenko 《Marine Georesources & Geotechnology》2020,38(5):527-538

Abstract

Two groups of oil slicks have been repeatedly detected in the Southern Caspian Sea, off Cape Sefidrud and close to the Iranian coast of the sea on the synthetic aperture radar (SAR) images acquired by the Sentinel-1A and Sentinel-1B satellites in April–June 2018. Analysis of the SAR images together with bathymetry, geological and geophysical data in geographic information system showed that these manifestations (oil slicks) visible on the sea surface have natural origin, related to the bottom seepage phenomenon and are associated with existing hydrocarbon system. Oil slicks are concentrated over the continental slope and related to local geological formations of the sedimentary cover having oil deposits related to paleo-delta of Sefidrud River. Our evidence shows that two seeps in this area are active and repeating. It is concluded that the SAR is an excellent tool for monitoring of seepage phenomenon. Moreover, results indicate that the use of remote methods to identify offshore natural oil seeps related to existing active petroleum system can be considered as a well-accepted approach to support oil and gas exploration in frontier areas such as the South Caspian Basin.  相似文献   

Reproductive biology and abundance of the white-dotted skate, Bathyraja albomaculata, in the Southwest Atlantic     

Ruocco  Natalia L.; Lucifora  Luis O.; Diaz de Astarloa  Juan M.; Wohler  Otto 《ICES Journal of Marine Science》2006,63(1):105-116

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Small-scale magnetic flux tube diagnostics in a solar flare     

Natalia Lozitska  Vsevolod Lozitskij 《Solar physics》1994,151(2):319-331

I ±V profiles of the Fei 5247 and 5250 lines in the 2B flare of June 16, 1989 have been analyzed. A bright knot of the flare outside the sunspot where the central intensity of H reached a peak value of 1.4 (relative to the continuum) has been explored. The Fei 5250/Fei 5247 magnetic line ratio based on the StokesV peak separations of these lines at five evolutionary phases of the flare (including the start of the flare, the flash phase, the peak and 16 min after the peak) has been analyzed. It was found that the StokesV peak separation for the Fei 5250 line was systematically larger than that of the Fei 5247 line. This is evidence for the presence in the flare of small-scale flux tubes with kG fields. The flux tube magnetic field strength was about 1.1 kG at the start of the flare and during the flash phase, 1.55 kG during the peak, and 1.38 kG 16 min after the peak. The filling factor,, appears to decrease monotonically during the flare.  相似文献   

Dzhida Ore District: Geology,Structural and Metallogenic Regionalization,Genetic Types of Ore Deposits,Geodynamic Conditions of Their Formation,Forecast, and Outlook for Development     

I. V. Gordienko  D. V. Gorokhovsky  O. K. Smirnova  V. S. Lantseva  R. A. Badmatsyrenova  D. A. Orsoev 《Geology of Ore Deposits》2018,60(1):1-32

Based on complex structural, rheological, and metallogenic studies, taking into account the results of earlier subject-specific, prospecting, mapping, and exploration works, it has been established that the geological structure of the district was caused by the ensimatic evolution of the Vendian–Early Paleozoic Dzhida island-arc system, in which oceanic and island-arc complexes served as a melanocratic basement for Late Paleozoic–Mesozoic active within-plate (riftogenic) processes, which gave rise to the formation of ore deposits and occurrences of strategic mineral commodities (Mo, W, Au, Pt, Ag, and rare elements, including REE). Mantle plumes and flows of deep-seated transmagmatic solutions (ore-forming fluids) played a critical role in these processes, the significance of which increases in upper crustal swarms of dikes and fault systems. The forecasts and development prospects of the Dzhida ore district envisage the expansion of geological prospecting and exploration, scientific research, and technological testing of ore for insight into strategic mineral commodities, as well as reanimation of mining within the areas of the Dzhida’s large territorial and industrial complex (TIC) in eastern Siberia.  相似文献   

Nitrate reduction potential of a fractured Middle Triassic carbonate aquifer in Southwest Germany     

Osenbr&#;ck  Karsten  Blendinger  Eva  Leven  Carsten  R&#;gner  Hermann  Finkel  Michael  Jakus  Natalia  Schulz  Hartmut  Grathwohl  Peter 《Hydrogeology Journal》2022,30(1):163-180

Hydrogeology Journal - Nitrate reduction constitutes an important natural mechanism to mitigate the widespread and persistent nitrate contamination of groundwater resources. In fractured aquifers,...  相似文献   

Mechanical Behavior of Clayey Soil Reinforced with Recycled Tire Rubber Using Chips and Fibers     

Jaramillo  Natalia Andrea Durán  dos Santos Ferreira  José Wilson  Malko  José Adriano Cardoso  Casagrande  Michéle Dal Toé 《Geotechnical and Geological Engineering》2022,40(6):3365-3378

Geotechnical and Geological Engineering - The volume of discarded tires continues to increase each year, becoming a major topic of concern for society. Motivated by this environmental issue, this...  相似文献