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Integrating isolated and riparian wetland modules in the PHYSITEL/HYDROTEL modelling platform: model performance and diagnosis 
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下载免费PDF全文 Maxime Fossey Alain N. Rousseau Fatima Bensalma Stéphane Savary Alain Royer 《水文研究》2015,29(22):4683-4702
Mathematical modelling is a well‐accepted framework to evaluate the effects of wetlands on stream flow and watershed hydrology in general. Although the integration of wetland modules into a distributed hydrological model represents a cost‐effective way to make this assessment, the added value brought by landscape‐specific modules to a model's ability to replicate basic hydrograph characteristics remains unclear. The objectives of this paper were the following: (i) to present the adaptation of PHYSITEL (a geographic information system) to parameterize isolated and riparian wetlands; (ii) to describe the integration of specific isolated wetland and riparian wetland modules into HYDROTEL, a distributed hydrological model; and (iii) to evaluate the performance of the updated modelling platform with respect to the capacity of replicating various hydrograph characteristics. To achieve this, two sets of simulations were performed (with and without wetland modules), and the added value was assessed at three river segments of the Becancour River watershed, Quebec, Canada, using six general goodness‐of‐fit indicators and 14 water flow criteria. A sensitivity analysis of the wetland module parameters was performed to characterize their impact on stream flows of the modelled watershed. Results of this study indicate the following: (i) integration of specific wetland modules can slightly increase the capacity of HYDROTEL to replicate basic hydrograph characteristics; and (ii) the updated modelling platform allows for the explicit assessment of the impact of wetlands (e.g. typology and location) on watershed hydrology. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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The bus route map is a diagram that aims to convey necessary information for map readers to find an appropriate way of moving from an origin to a destination. Design of bus route map is a complicated and time-consuming task that requires careful consideration of readability and aesthetics. This paper proposes a new computational method for designing bus route maps. The method helps us to reduce six types of undesirable elements in bus route maps, i.e., gap, shift, crossing, overlap, misalignment, and acute bend. The method consists of two phases: line layout phase determines the relative order of bus routes on each road segment and map layout phase calculates the actual position of bus routes drawn on a map. This paper applies the method to the design of bus route maps of Chiba City, Japan. The result supports the effectiveness of the method as well as reveals open topics for future research. 相似文献
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Stephen P. Carey Aaron B. Camens Matthew L. Cupper Rainer Grün John C. Hellstrom Stafford W. McKnight Iain Mclennan David A. Pickering Peter Trusler Maxime Aubert 《Quaternary Science Reviews》2011,30(5-6):591-610
A diverse assemblage of late Pleistocene marsupial trackways on a lake bed in south-western Victoria provides the first information relating to the gaits and morphology of several megafaunal species, and represents the most speciose and best preserved megafaunal footprint site in Australia. The 60–110 ka volcaniclastic lacustrine sedimentary rocks preserve trackways of the diprotodontid Diprotodon optatum, a macropodid (probably Protemnodon sp.) and a large vombatid (perhaps Ramsayia magna or ‘Phascolomys’ medius) and possible prints of the marsupial lion, Thylacoleo carnifex. The footprints were imprinted within a short time period, demonstrating the association of the taxa present, rather than the time-averaged accumulations usually observed in skeletal fossil deposits. Individual manus and pes prints are distinguishable in some trackways, and in many cases some digital pad morphology is also present. Several parameters traditionally used to differentiate ichnotaxa, including trackway gauge and the degree of print in-turning relative to the midline, are shown to be subject to significant intraspecific variation in marsupials. Sexual dimorphism in the trackway proportions of Diprotodon, and its potential for occurrence in all large bodied, quadrupedal marsupials, is identified here for the first time. 相似文献
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Maxime Le Goff Bernard Henry Lucien Daly 《Physics of the Earth and Planetary Interiors》1992,70(3-4):201-204
A statistical method is proposed for the smoothing of polar wander paths and for giving their confidence limits by the mean of successive ellipses. The method is fully parametrical and is based on the relations between the inertia matrix and the parameters of the Fisher distribution, from which a bivariate form is deduced. An elementary tensorial calculation gives the parameters of the confidence ellipse around a vectorial weighted mean, for any unimodal set of vectors. This model can also be used for other statistical tests, wherever the rotational symmetry hypothesis is not consistent (i.e. the fold test). 相似文献
5.
Spectroscopic analysis (FTIR, Raman) of water in mafic and intermediate glasses and glass inclusions 总被引：1，自引：0，他引：1
Maxime Mercier Andrea Di Muro Nicole Métrich Olfa Belhadj 《Geochimica et cosmochimica acta》2010,74(19):5641-5656
Micro-Raman spectroscopy, even though a very promising technique, is not still routinely applied to analyse H2O in silicate glasses. The accuracy of Raman water determinations critically depends on the capability to predict and take into account both the matrix effects (bulk glass composition) and the analytical conditions on band intensities. On the other hand, micro-Fourier transform infrared spectroscopy is commonly used to measure the hydrous absorbing species (e.g., hydroxyl OH− and molecular H2O) in natural glasses, but requires critical assumptions for the study of crystal-hosted glasses. Here, we quantify for the first time the matrix effect of Raman external calibration procedures for the quantification of the total H2O content (H2OT = OH− + H2Om) in natural silicate glasses. The procedures are based on the calibration of either the absolute (external calibration) or scaled (parameterisation) intensity of the 3550 cm−1 band. A total of 67 mafic (basanite, basalt) and intermediate (andesite) glasses hosted in olivines, having between 0.2 and 4.8 wt% of H2O, was analysed. Our new dataset demonstrates, for given water content, the height (intensity) of Raman H2OT band depends on glass density, reflectance and water environment. Hence this matrix effect must be considered in the quantification of H2O by Raman spectroscopy irrespective of the procedure, whereas the parameterisation mainly helps to predict and verify the self-consistency of the Raman results. In addition, to validate the capability of the micro-Raman to accurately determine the H2O content of multicomponent aluminosilicate glasses, a subset of 23 glasses was analysed by both micro-Raman and micro-FTIR spectroscopy using the band at 3550 cm−1. We provide new FTIR absorptivity coefficients (ε3550) for basalt (62.80 ± 0.8 L mol−1 cm−1) and basanite (43.96 ± 0.6 L mol−1 cm−1). These values, together with an exhaustive review of literature data, confirm the non-linear decline of the FTIR absorptivity coefficient (ε3550) as the glass depolymerisation increases. We demonstrate the good agreement between micro-FTIR and micro-Raman determination of H2O in silicate glasses when the matrix effects are properly considered. 相似文献
6.
Mathieu Duval Christophe Falguères Jean‐Jacques Bahain Rainer Grün Qingfeng Shao Maxime Aubert John Hellstrom Jean‐Michel Dolo Jordi Agusti Bienvenido Martínez‐Navarro Paul Palmqvist Isidro Toro‐Moyano 《第四纪科学杂志》2011,26(6):603-615
The palaeontological site of Venta Micena (Orce, Andalusia, Spain) lies in the eastern sector of the Guadix–Baza basin, one of the best documented areas in Europe for Plio‐Pleistocene biostratigraphy. The combination of biochronological and palaeomagnetic results, combined with the radiometric data obtained for Atapuerca Sima del Elefante, indicated that the Venta Micena stratum was formed between the Jaramillo and Olduvai palaeomagnetic events, most likely between 1.22 and 1.77 Ma. Five fossil teeth from two outcrops (sites A and B) were selected to assess the potential of combined uranium series–electron spin resonance (US‐ESR) dating of Early Pleistocene sites. Although the US‐ESR results of the first outcrop showed a large scatter between the three teeth, the mean age of 1.37 ± 0.24 Ma can be considered a reasonable age estimate for Venta Micena. The mean ESR age of 0.62 ± 0.03 Ma obtained for site B seems to be a severe underestimation when compared with the independent age control. This underestimation is attributed to a relative recent U‐mobilization event that led to some U‐leaching. The results show that any ESR age calculations of old samples are extremely sensitive to variations in the measured 230Th/234U ratios in dental tissues. Although the results demonstrate that ESR can in principle be applied to Early Pleistocene sites, they also reveal the complexity of dating such old teeth. It is necessary to continue research in several directions, such as study of the behaviour of ESR signals in old teeth and understanding recent U‐mobilization processes, to improve the reliability of the combined US‐ESR dating method applied to Early Pleistocene times, a period for which the number of available numerical dating techniques is very limited. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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Maxime Lion Béatrice Ledésert Frédéric Skoczylas Philippe Recourt Thierry Dubois 《地学学报》2004,16(6):351-357
Many poromechanical studies of rocks give little regard to the micropetrographic observation of their constituents. The aim of this study is to show how such a detailed study can help understand and provide more precision on the poromechanical behaviour of the material. The rock studied here is an oolitic limestone. Micropetrography reveals the nature of the constituents (calcite, mostly in the form of fine‐grained micrite), their abundance, their organization (micrite organized in ooids linked by a calcitic cement, small‐sized highly connected isotropic porosity, scarce unconnected porosity) and the structure of the rock (global isotropy, small heterogeneities due to sedimentological phenomena, no microcracks). Micropetrography completes the information obtained by poromechanics in that it allows the observation of elements deduced from macroscopical tests. The aim of this paper is to show the effect of microporosity on permeability and flow in a rock where microporous grains are in contact with each other. 相似文献
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Gérald Darnis Dominique Robert Corinne Pomerleau Heike Link Philippe Archambault R. John Nelson Maxime Geoffroy Jean-éric Tremblay Connie Lovejoy Steve H. Ferguson Brian P. V. Hunt Louis Fortier 《Climatic change》2012,115(1):179-205
As part of the Canadian contribution to the International Polar Year (IPY), several major international research programs have focused on offshore arctic marine ecosystems. The general goal of these projects was to improve our understanding of how the response of arctic marine ecosystems to climate warming will alter food web structure and ecosystem services provided to Northerners. At least four key findings from these projects relating to arctic heterotrophic food web, pelagic-benthic coupling and biodiversity have emerged: (1) Contrary to a long-standing paradigm of dormant ecosystems during the long arctic winter, major food web components showed relatively high level of winter activity, well before the spring release of ice algae and subsequent phytoplankton bloom. Such phenological plasticity among key secondary producers like zooplankton may thus narrow the risks of extreme mismatch between primary production and secondary production in an increasingly variable arctic environment. (2) Tight pelagic-benthic coupling and consequent recycling of nutrients at the seafloor characterize specific regions of the Canadian Arctic, such as the North Water polynya and Lancaster Sound. The latter constitute hot spots of benthic ecosystem functioning compared to regions where zooplankton-mediated processes weaken the pelagic-benthic coupling. (3) In contrast with another widely shared assumption of lower biodiversity, arctic marine biodiversity is comparable to that reported off Atlantic and Pacific coasts of Canada, albeit threatened by the potential colonization of subarctic species. (4) The rapid decrease of summer sea-ice cover allows increasing numbers of killer whales to use the Canadian High Arctic as a hunting ground. The stronger presence of this species, bound to become a new apex predator of arctic seas, will likely affect populations of endemic arctic marine mammals such as the narwhal, bowhead, and beluga whales. 相似文献
10.
Can a 25-year trend in Soudano-Sahelian vegetation dynamics be interpreted in terms of land use change? A remote sensing approach 总被引：3，自引：0，他引：3
Agnès Bégué Elodie VintrouDenis Ruelland Maxime Claden 《Global Environmental Change》2011,21(2):413-420
This study is based on the premise that, in the Sahel/Sudanian belt of Africa, the main determinants of interannual variation in vegetation dynamics are rainfall and land cover type. We analyzed the spatio-temporal sensitivity of the NOAA-AVHRR 8 km-resolution vegetation index (NDVI) to (i) annual rainfall variability (0.5° × 0.5° resolution) acquired over a 25-year period (1982-2006); and (ii) land use changes in the different eco-climatic regions of the Bani catchment in Mali (130 000 km2). During the period 1982-2006, there was no clear trend in rainfall over the catchment, whereas there was a strong positive trend in the NDVI, both when the NDVI values were corrected using annual rainfall variability and when they were not. We divided the catchment into three eco-climatic regions based on the relationship between the annual NDVI and rainfall. In each region, we analyzed the observed greening in relation to changes in land use after correcting for the effect of annual rainfall on the NDVI. Results show that there is a mixed level of agreement between the land cover changes at the grid cell scale and the spatial pattern of the NDVI trend. Increased cropping does not explain the increase in the annual NDVI, except in the Sahelian part of the catchment. We hypothesize that the natural vegetation dynamics related to the non-linear rainfall patterns during the 25-year study period were responsible for these results. 相似文献