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The topographic features on Venus are named with female names: craters and paterae have names of famous women as well as female first names, non-crater features have names of mythological characters. The first 80 names appeared on the maps after the Pioneer Venus mission; about 300 more names after the Venera 15 and 16 missions. 376 features of 17 types are now named. All the names are listed with their coordinates and attribute data. A large number of new names will be necessary after the MAGELLAN mission when detailed maps will be produced for nearly the whole surface of Venus.'Geology and Tectonics of Venus', special issue edited by Alexander T. Basilevsky (USSR Acad. of Sci., Moscow), James W. Head (Brown University, Providence), Gordon H. Pettengill (MIT, Cambridge, Massachusetts) and R. S. Saunders (J.P.L., Pasadena). 相似文献
22.
Nicoletta Nesto Martina Bertoldo Cristina Nasci Luisa Da Ros 《Marine environmental research》2004,58(2-5):287
A multiple biomarker approach was adopted in a seasonal study carried out in the Lagoon of Venice, with the double aim of evaluating the natural and anthropic stresses influencing the biological responses of mussel (Mytilus galloprovincialis) and of assessing the effects due to spatial rather than temporal variations.Biochemical (aldehyde dehydrogenase and catalase activities), cellular (neutral red retention time) and physiological (survival in air and condition index) biomarkers were determined in mussels collected in four differently impacted lagoon areas.Multivariate analysis showed that samples were distributed mainly according to temperature and four seasonal groups were identified. The combination of spatial and temporal information enabled us to distinguish physiological variations due to natural causes from those due to anthropic stress, and to identify the sampling period when several biomarkers are less influenced by both natural and endogenous factors. 相似文献
23.
A multiple biomarker approach was adopted in a seasonal study carried out in the Lagoon of Venice, with the double aim of evaluating the natural and anthropic stresses influencing the biological responses of mussel (Mytilus galloprovincialis) and of assessing the effects due to spatial rather than temporal variations. Biochemical (aldehyde dehydrogenase and catalase activities), cellular (neutral red retention time) and physiological (survival in air and condition index) biomarkers were determined in mussels collected in four differently impacted lagoon areas. Multivariate analysis showed that samples were distributed mainly according to temperature and four seasonal groups were identified. The combination of spatial and temporal information enabled us to distinguish physiological variations due to natural causes from those due to anthropic stress, and to identify the sampling period when several biomarkers are less influenced by both natural and endogenous factors. 相似文献
24.
Chiara Montemagni Rodolfo Carosi Nicoletta Fusi Salvatore Iaccarino Chiara Montomoli Igor M. Villa Stefano Zanchetta 《地学学报》2020,32(3):215-224
Vorticity estimates based on porphyroclasts analysis are limited by the extrapolation to three dimensions of two‐dimensional data. We describe a 3D approach based on the use of X‐ray micro‐computed tomography that better reflects the real 3D geometry of the porphyroclasts population. This new approach for kinematic vorticity analysis in the Munsiari Thrust mylonites, the lower boundary of the Main Central Thrust zone (MCTz) in Indian Himalaya, indicates a large pure shear component during non‐coaxial shearing. 40Ar/39Ar ages of micas along the mylonitic foliation of the Munsiari and Vaikrita thrusts (the upper boundary of the MCTz) constrain thrust activity to 5–4 and 8–9 Ma, respectively. Available kinematic vorticity analyses of the Vaikrita mylonites suggest the dominance of a simple shear component. Combining these data, we suggest that the southward and structurally downward shift of deformation along the MCTz was accompanied by a progressive increase in the pure shear component in a general shear flow. 相似文献
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The magnitude and even direction of recent Antarctic climate change is still debated because the paucity of long and complete
instrumental data records. While along Antarctic Peninsula a strong warming coupled with large retreat of glaciers occurred,
in continental Antarctica a cooling was recently detected. Here, the first existing permafrost data set longer than 10 years
recorded in continental Antarctica is presented. Since 1997 summer ground surface temperature showed a strong warming trend
(0.31°C per year) although the air temperature was almost stable. The summer ground surface temperature increase seemed to
be influenced mainly by the increase of the total summer radiation as confirmed also by the increase of the summer thawing
degree days. In the same period the active layer exhibited a thickening trend (1 cm per year) comparable with the thickening
rates observed in several Arctic locations where air warming occurred. At all the investigated depths permafrost exhibited
an increase of mean annual temperature of approximately 0.1°C per year. The dichotomy between active layer thickness and air
temperature trends can produce large unexepected and unmodelled impacts on ecosystems and CO2 balance. 相似文献
27.
Letizia Sabetta Annita Fiocca Lucia Margheriti Fabio Vignes Alberto Basset Olga Mangoni Gian Carlo Carrada Nicoletta Ruggieri Carmela Ianni 《Estuarine, Coastal and Shelf Science》2005,63(4):645-663
This study focuses on body size–abundance distributions of nano- and micro-phytoplankton guilds in coastal marine areas of the Southern Adriatic–Ionian region. The aim of the study was to evaluate the occurrence of common patterns of body size–abundance distributions in relation to physical, chemical and biological environmental forcing factors and to taxonomic composition of phytoplankton guilds. This paper is based on data collected during four oceanographic cruises carried out seasonally along the Southern Apulian coast (Adriatic and Ionian Seas, SE Italy) as a part of the INTERREG II Italy–Greece Program. The study was performed at 21 stations located on 7 transects perpendicular to the coastline, with 3 stations per transect at a distance of 3, 9 and 15 NM from the coastline. At each station, profiles of the major physical features of the water were determined and water samples were collected for phytoplankton and nutrient analysis. Overall, 320 nano- and micro-phytoplankton taxa were identified, 76% of which at species level, with phytoplankton cells ranging in size from 0.008 to 4697.54 ng. Body size–abundance distributions showed some common features: they were relatively invariant (average similarity 65%) with respect to taxonomic composition (average similarity 32%), right skewed (90%), leptokurtic (77%) and log normal (76%). Moreover, abiotic, biotic and spatial ecosystem components accounted for up to 75% of body size–abundance distribution variation. The results of this study suggest that body size–abundance distributions are an intrinsic property of marine phytoplankton communities, emphasising functional dependence on ecological constraints related to trophic factors and intra-guild coexistence relationships. 相似文献