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111.
Lucas Fernandez Reyes 《地理信息系统科学与遥感》2013,50(1):68-73
Remote sensing inventories of the land and marine resources of Cuba, both from satellite and aerial platforms, are assessed in terms of their contributions to research on the country's physical and economic geography. Under the auspices of an international cooperative program “Interkosmos,” maps of many types have been upgraded, the costs of surveys have been reduced dramatically, and the potential for monitoring natural and human-induced change is being realized more fully. In addition, a study of weather and other conditions affecting image quality led to a determination of optimal times for conducting remote sensing surveys. Translated from: Vestnik Moskovskogo Universiteta, geografiya, 1988, No. 3, pp. 36-41, by Edward Torrey, Alexandria, VA 22308. 相似文献
112.
The aim of the study is an impact analysis of global climate change on regional hydrology with special emphasis on discharge
conditions and floods. The investigations are focussed on the major part of the German Rhine catchment with a drainage area
of approx. 110,000 km2. This area is subdivided into 23 subcatchments. In a first step, the hydrological model HBV-D serves to simulate runoff conditions
under present climate for the individual subbasins. Simulated, large scale atmospheric fields, provided by two different Global
Circulation Models (GCMs) and driven by the emission scenario IS95a (“business as usual”) are then used as input to the method
of expanded downscaling (EDS). EDS delivers local time series of scenario climate as input to HBV-D. In a final step, the
investigations are focussed on the assessment of possible future runoff conditions under the impact of climate change. The
study indicates a potential increase in precipitation, mean runoff and flood discharge for small return intervals. However,
the uncertainty range that originates from the application of the whole model chain and two different GCMs is high. This leads
to high cumulative uncertainties, which do not allow conclusions to be drawn on the development of future extreme floods. 相似文献
113.
Mariana Terossi Lucas S. Torati Ivana Miranda Marcelo A. Scelzo Fernando L. Mantelatto 《Marine Ecology》2010,31(4):584-591
Pagurus exilis (Benedict, 1892) is an endemic South Atlantic hermit crab with a distribution ranging from Rio de Janeiro State, Brazil, to Buenos Aires Province, Argentina. The present study analyzed the reproduction of two populations at the extremes of this geographical distribution, and compared their reproductive period, fecundity, and changes in egg size and egg volume during the incubation period in order to assess the variability over this latitudinal range. Hermit crabs were collected monthly over a 2‐year period. In total, 108 females were analyzed for Brazil (44 non‐ovigerous and 64 ovigerous), and 141 for Argentina (87 non‐ovigerous and 54 ovigerous). Reproduction in Brazil occurs year‐round, with peaks in the fall and winter seasons; in Argentina reproduction occurs only in spring and summer. The Brazilian ovigerous females were significantly larger than the Argentina ones (Brazil: SL = 5.33 ± 1.45 mm; Argentina: SL = 4.15 ± 0.52 mm; P < 0.001). The fecundity was 1447 ± 831 eggs (317 to 2885) in Brazil and 987 ± 711 eggs (114 to 2665) in Argentina, with a trend towards higher fecundity in Brazil. Eggs in the Argentina population were larger than those in Brazil for all the three stages investigated, and no changes in egg volume were found during egg development for both populations. The reproductive traits of the two populations showed some important differences, which may reflect adaptations to local environmental conditions, demonstrating a high plasticity of reproductive features of the species in Brazilian and Argentine waters. The strategy adopted by the Argentina population involves a lower production of larger eggs compared to the population in Brazil; this lower production is associated with reproduction in cold‐water regions. 相似文献
114.
Gerald Grellet-Tinner Michael B.Thompson Lucas E.Fiorelli Eloísa Argaaraz Laura Codorniú E.Martín Hechenleitner 《地学前缘(英文版)》2014,5(6):759-765
The increasing number of fossil pterosaur eggs sheds light on nesting environments and breeding be- haviors of these extinct flying reptiles. Here we report the first partial three-dimensional egg of the pterosaur, Pteroduustro guinazui, from central Argentina. The specimen was discovered from the same Albian deposits as the exceptional R guinazui embryo described in 2004. Microscopic characterizations indicate a pristine preservation of the 50 Bm thick calcium carbonate, which differs significantly from the soft shell of Chinese pterosaur eggs. Estimate of the eggshell conductance implies that the nest had a minimum moisture content of 75%. This moisture estimate, combined with geological and taphonomical data, suggests that P. guinazui may have adopted a nesting strategy similar to those of grebes and flamingos rather than being buried on land, as previously hypothesized. Moreover, our results demon- strate that the nesting paleoenvironment of this pterosaur species was closely linked to a mesohaline lacustrine ecosystem in a basin governed by regional tectonic subsidence, a setting characteristic for the feeding and reproduction of modern flamingos. 相似文献
115.
Ben Burningham D. J. Pinfield S. K. Leggett C. G. Tinney M. C. Liu † D. Homeier A. A. West A. Day-Jones N. Huelamo T. J. Dupuy Z. Zhang D. N. Murray N. Lodieu D. Barrado y Navascués S. Folkes M. C. Galvez-Ortiz H. R. A. Jones P. W. Lucas M. Morales Calderon M. Tamura 《Monthly notices of the Royal Astronomical Society》2009,395(3):1237-1248
116.
117.
Tracing of dissolved organic matter from the Sepetiba Bay (Brazil) by PARAFAC analysis of total luminescence matrices 总被引:2,自引:0,他引:2
Luciani X Mounier S Paraquetti HH Redon R Lucas Y Bois A Lacerda LD Raynaud M Ripert M 《Marine environmental research》2008,65(2):148-157
Fluorescent excitation-emission matrices (FEEM) of the fluorescent dissolved organic matter (FDOM) are widely used for DOM characterization and tracing. In this work, a set of FEEM from sampling campaigns in the Sepetiba Bay (Brazil) was decomposed into independent components using the parallel factor analysis (PARAFAC) algorithm. Four independent components were extracted describing the total fluorescence of the FDOM. The well described peaks A, C, M, B and T were found, and a new peak, A', linked to the C peak, was detected. Relative contribution of each of four components to the total fluorescence confirms that the coastal water has DOM of terrestrial origin, except for the 275Ex/400-500Em range (nm), which primarily occurs in marine waters. 相似文献
118.
Concentrations of contaminants in surface water samples collected in west-central Indiana impacted by acidic mine drainage 总被引:1,自引:0,他引:1
The results of analyses of surface waters collected from a variety of locations in west-central Indiana indicate extensive contamination by acidic mine drainage. These samples had pH values as low as 2.1 and total iron concentrations as high as 1200 mg1–1. The speciation of iron, expressed as the ratio [Fe(II)]/[Fe(III)] ranged from 0.08 to 8.27. Measured lead concentrations were as high as 811 mgl–1. In addition, the concentrations of nitrate and sulfate ions were as high as 359 and 624 mgl–1, respectively. 相似文献
119.
This editorial introduction to the themed issue is divided into four parts. We begin with outlining five reasons for more sustained attention to ageing and old age in human geography and go onto discuss two major challenges for geographical inquiry into ageing and later life. One of these is examining embodiment in ways that keep both its social/cultural aspects and its biological/physiological dimensions in sharp focus; the other concerns the challenge of considering time, or rather spatiotemporality, in all its facets. With regard to the latter we argue that the life-course concept can be helpful in this regard, especially if attention is paid to transitions as well as to slow, difficult-to-identify forms of change and if life-courses are understood in terms of folds. Thinking in these terms opens up a perspective according to which ageing and space can be analysed as entwined becomings. We conclude by positioning the contributions in this issue vis-à-vis the perspective developed in this piece. 相似文献
120.
Lucas May Petry Carlos Andres Ferrero Luis Otavio Alvares Chiara Renso Vania Bogorny 《Transactions in GIS》2019,23(5):960-975
The large amount of semantically rich mobility data becoming available in the era of big data has led to a need for new trajectory similarity measures. In the context of multiple‐aspect trajectories, where mobility data are enriched with several semantic dimensions, current state‐of‐the‐art approaches present some limitations concerning the relationships between attributes and their semantics. Existing works are either too strict, requiring a match on all attributes, or too flexible, considering all attributes as independent. In this article we propose MUITAS, a novel similarity measure for a new type of trajectory data with heterogeneous semantic dimensions, which takes into account the semantic relationship between attributes, thus filling the gap of the current trajectory similarity methods. We evaluate MUITAS over two real datasets of multiple‐aspect social media and GPS trajectories. With precision at recall and clustering techniques, we show that MUITAS is the most robust measure for multiple‐aspect trajectories. 相似文献