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91.
Isabel Pôças João Gonçalves Bruno Marcos Joaquim Alonso Pedro Castro João P. Honrado 《International journal of geographical information science》2014,28(11):2356-2371
This article proposes and illustrates a practical methodological framework to evaluate the fitness for use of spatial data sets for environmental and ecological applications, focusing on user requirements for specified application contexts. The methodology is based on the use of metadata to analyze similarity between the data characteristics and the user’s needs or expectations for several quality indicators. Additionally, the concept of ‘critical factors’ is introduced in this framework, allowing users to define which quality indicators have greater importance given their own requirements or expectations and the specified application contexts. The proposed methodology further allows integrating and interconnecting the spatial data quality (SDQ) evaluation methodology with metadata geoportals in WebGIS platforms, facilitating its operation by users from non-spatial disciplines and with often limited expertise on this subject. Examples of the evaluation of fitness for use for specific application contexts within the project BIO_SOS (‘Biodiversity Multi-SOurce Monitoring System: From Space To Species’ FP7 project) are presented. By providing a prompt and straightforward evaluation tool, the proposed methodology can encourage the implementation of SDQ evaluation routines in ecological assessment and monitoring programs, promoting a more adequate use of geospatial data and ultimately contributing to well-supported policy and management decisions. 相似文献
92.
Size‐frequency distributions can support reliable inferences concerning population dynamics of brachiopods, but only a few data are available so far. In this study, length and width frequency distributions of dead specimens of the Recent brachiopods Joania cordata and Argyrotheca cuneata from the Marine Protected Area ‘Secche di Tor Paterno’, Central Tyrrhenian Sea, Italy (41°35′ N, 12°20′ E), are reported in order to add new data about size‐frequency distributions of brachiopods. The studied specimens came from death assemblages in the coralligenous substrate, in the Posidonia oceanica meadows, and in the sand channels. The observed patterns vary from left‐skewed (J. cordata) to right‐skewed (A. cuneata), indicating respectively a low and high mortality of smaller individuals. Significant differences between the coralligenous substrate and the P. oceanica meadow were observed for both species, revealing a variation among different habitats. All length and width distributions are clearly polymodal, but the biological meaning of the peaks is difficult to interpret, as the two species seem to have a 2‐year life span. A biometric analysis of shell sizes revealed that length and width are the most variable parameters during the growth of the animal. 相似文献
93.
Ana Carolina F. de Vasconcelos Sandro L. Schlindwein Marcos A. Lana Alfredo C. Fantini Michelle Bonatti Luiz R. D’Agostini Sergio R. Martins 《Climatic change》2014,127(1):73-81
The La Plata Basin (LPB) is one of the most important regions for agriculture and livestock production in South America, playing a central role in the world food production and food security. Within its borders is also located the whole Brazilian Pantanal region. Identifying the most important land use sectors in LPB as well as the changes observed in the past years is fundamental to recognize which areas of the basin might be more vulnerable to climate change in order to design adaptation strategies. A general characterization of land use and livestock production of Brazilian LPB was done by using the System of Automatic Retrieving (SIDRA) of Brazilian Institute of Geography and Statistics (IBGE) platform as the major source of data. It was observed expressive increases in land areas used for temporary crops, such as soybean, sugarcane, and maize, as well as increases in poultry and swine production. These important changes in agricultural land use and livestock production are currently associated to non-climatic drivers, but this dynamic might be strongly affected by the consequences of climate change and variability, with negative socio-economic impacts for the whole region. 相似文献
94.
A microbeam (electron microprobe, X-ray diffraction and Raman) study of pseudomorphs after magmatic perovskite from kimberlite (Iron Hill, Wyoming, USA) and carbonatite (Prairie Lake, Ontario, Canada) showed that the early product of perovskite replacement in these samples is kassite, a monoclinic (space group P21/a) polymorph of CaTi2O4(OH)2. This mineral can be readily distinguished from its dimorph cafetite (space group P21/n) based on the presence of strong signals at ~120, 300, 330, 450, 470 and 690 cm?1, and the absence or very low intensity of signals at ~250, 420, 600, 800 and 825 cm?1 in its Raman spectrum. The strongest X-ray diffraction lines, measured for the Prairie Lake material, are [d obs in Å (I) hkl]: ~3.29 (100) 022; 112, \( {\mathrm{11}}{\overline 2} \) ; 1.764 (61) \( {\mathrm{13}}{\overline 4} \) ; 2.284 (45) 132; 2.601 (24) 130; 2.050 (17) 222; 4.81 (16) 002; 2.034 (15) 042; 2.308 (14) 202; 1.778 (14) \( {\mathrm{20}}{\overline 4} \) . Diffraction lines at 3.60, 2.99, 2.79, 2.57, 2.56 and 1.91 Å, characteristic of cafetite, are not observed. The electron-microprobe analyses of kassite give formulae close to the stoichiometric composition. Progressive Ca leaching leads to replacement of kassite by anatase + calcite, which are also commonly observed as direct products of perovskite alteration in silica-undersaturated igneous rocks. Raman spectroscopy is the fastest and most reliable technique to identify submicroscopic anatase–calcite intergrowths that can be easily mistaken for kassite (cafetite) based on electron-microprobe data. Thermodynamic calculations indicate that conversion of perovskite into kassite and, subsequently, anatase requires initially high levels of f(H2O) in the system, followed by an increase in f(CO2) at either decreasing or constant T and f(H2O). The implications of perovskite–kassite–anatase phase relations for deciphering the late-stage evolution of kimberlites and carbonatites are discussed. 相似文献
95.
Nguyen Nghia Hung José Miguel Delgado Vo Khac Tri Le Manh Hung Bruno Merz András Bárdossy Heiko Apel 《水文研究》2012,26(5):674-686
The Mekong Delta is one of the largest and most intensively used estuaries in the world. Each year it witnesses widespread flooding which is both the basis of the livelihood for more than 17 million people but also the major hazard. Therefore, a thorough understanding of the hydrologic and hydraulic features is urgently required for various planning purposes. While the general causes and characteristics of the annual floods are understood, the inundation dynamics in the floodplains in Vietnam which are highly controlled by dikes and other control structures have not been investigated in depth. Especially, quantitative analyses are lacking, mainly due to scarce data about the inundation processes in the floodplains. Therefore, a comprehensive monitoring scheme for channel and floodplain inundation was established in a study area in the Plain of Reeds in the northeastern part of the Vietnamese Delta. This in situ data collection was complemented by a series of high‐resolution inundation maps derived from the TerraSAR‐X satellite for the flood seasons 2008 and 2009. Hence, the inundation dynamics in the channels and floodplains, and the interaction between channels and floodplains, could be quantified for the first time. The study identifies the strong human interference which is governed by flood protection levels, cropping patterns and communal water management. In addition, we examine the tidal influence on the inundation in various parts of the Delta, since it is expected that climate change‐induced sea level rise will increase the tidal contribution to floodplain inundation. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
96.
M. Bruno G. Cremonese S. Marchi 《Monthly notices of the Royal Astronomical Society》2006,367(3):1067-1071
In this work, we calculate the vapour and neutral Na production rates on the Moon, as due to the impacts of meteoroids in the radius range of 10−8 –0.15 m. We limit our calculations to this size range, since meteoroids with radius larger than 0.15 m have not been found to be important for the production of the exosphere in a time interval comparable with that of the observations.
We have considered a new dynamical model of the flux of meteoroids at the heliocentric distance of the Moon, regarding objects in the radius range of 10−2 –0.15 m. Instead, the flux of smaller meteoroids (radius range 10−8 –10−2 m) has been calculated using the two distributions adopted by Cintala and Love & Brownlee.
The results of our model are that (i) the neutral Na production rate is ∼3–4.9 × 104 atoms cm−2 s−1 , slightly larger than the previous estimates (∼2–3 × 104 atoms cm−2 s−1 ) , and (ii) only about 6 per cent of neutral Na is produced by the impacts of meteoroids in the size range 10−3 –0.15 m, whereas about 94 per cent of the Na comes from the 10−5 –10−3 m size range. 相似文献
We have considered a new dynamical model of the flux of meteoroids at the heliocentric distance of the Moon, regarding objects in the radius range of 10
The results of our model are that (i) the neutral Na production rate is ∼3–4.9 × 10
97.
We derive the transformations to convert the state vector in cartesian coordinates into geometric orbital elements (and conversely
the geometric elements into the state vector) for a test particle moving around an oblate planet. These transformations arise
from the epicyclic theory and are accurate to second order in eccentricity and inclination. This paper is written to be directly
used for computational purposes, such as the numerical study of ring dynamics. 相似文献
98.
Gilberto A. Albertão Eduardo A.M. Koutsoukos Marília P.S. Regali Moses Attrep Jr Paulo P. Martins Jr 《地学学报》1994,6(4):366-375
A preliminary integrated study of a Cretaceous-Tertiary (K/T) boundary section in Pernambuco, northeastern Brazil, provides evidence for an extraterrestrial bolide impact in the earliest Danian. A non-graded, nodular carbonate mudstone/wackestone bed is interpreted as a slump or a mud Flow deposit, induced by a tsunami event or by a gravity mass movement during a sea-level lowstand, the former possibly generated by the K/T boundary Yucatán impact. This bed overlies marlstones deposited in an upper bathyal environment and marks the top of the Cretaceous. Nearly all known latest Maastrichtian planktonic foraminifera are recovered from the Cretaceous strata. Iridium shows a marked peak in a thin hemipelagic claystone layer, about 75 cm above the K/T boundary, deposited in a middle to deep neritic environment. The claystone overlies alternating beds of finegrained limestones and marlstones and a 50 cm-thick graded bioclastic packstone, which rests upon a marly limestone breccia of the lowermost Danian. Abundant reworked Cretaceous and rare lowermost Danian microfossils (e.g. E. edita, E. eobulloides, E. fringa, G. irregularis, P. eugubina, P. cf. pseudobulloides, W. claytonensis and W. hornerstownensis ) have been recovered from these strata. These lowermost Danian beds record the sudden appearance of abundant shock-metamorphosed quartz grains, with several sets of intersecting deformation lamellae and microtektite-like microspherules. This suggests that these deposits were formed by an additional tsunami caused by a second impact event in the earliest Danian, near or at the boundary between the Palaeocene P α and P 1a foraminiferal zones. Impact-derived material has not been found in the uppermost Cretaceous beds. 相似文献
99.
Spectro-imaging of Venus' nightside in the 2.3-μm window provides a powerful means of probing the lower atmosphere in the 25-40 km altitude range. We present observations recorded at the NASA/IRTF in February 2003 and August 2004, using the SpeX spectro-imager in the 2.1-2.5-μm region. Abundances of CO and OCS have been derived as a function of latitude for different longitudes. The CO abundance increases by about 15% between the equatorial region and higher latitudes (±40°). No longitudinal or temporal variations are observed. The OCS abundance shows the opposite variation in observational sets with sufficient S/N. These variations and anticorrelation are consistent with upwelling motions in the equatorial region and downwelling at higher latitudes. 相似文献
100.
Xavier Bruna Catarino Egydio-Silva Marcos Sadowski Georg Robert de Assis Silva Bruno Takara Victor Junji 《Geotechnical and Geological Engineering》2022,40(3):1345-1361
Geotechnical and Geological Engineering - To optimize the prediction of structural geological conditions in the underground as of data collected at the surface, due to the usual great uncertainties... 相似文献