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排序方式： 共有96条查询结果，搜索用时 31 毫秒
41.
Maria V. MAZZAMUTO Andrea GALIMBERTI Giacomo CREMONESI Benoît PISANU Jean‐Louis CHAPUIS Jan STUYCK Giovanni AMORI Haijun SU Gaetano ALOISE Damiano G. PREATONI Lucas A. WAUTERS Maurizio CASIRAGHI Adriano MARTINOLI 《Integrative zoology》2016,11(3):214-228
Integrative taxonomy, a multi‐disciplinary approach adding modern techniques to traditional morphology‐based methods (e.g. molecular and morphological criteria), can play an important role in bioinvasion research to identify introduced taxa, discover pathways of introduction and inform authorities to control and prevent future introductions. The present study is the first on introduced populations of Callosciurus, Asiatic tree squirrels, known as potentially invasive species in Europe (Italy, Belgium and France). We combined molecular (mitochondrial DNA markers: CoxI, D‐loop) and morphometric analysis on skulls, comparing them to the widest morphological and molecular datasets ever assembled for Callosciurus. Squirrels collected in Italy and Belgium share the same haplotypes and skull characteristics, but are conspicuously different from the French population in Antibes. Genetic data revealed close similarity between French squirrels and Pallas's squirrels, Callosciurus erythraeus, from Taiwan, China. Italian and Belgian squirrels formed an independent taxonomic lineage in genetic analyses, whose taxonomic rank needs further investigation. The morphological and morphometric characteristics of these 2 populations are, however, similar to known specimens assigned to Callosciurus erythraeus. These results may indicate a common origin for the populations found in Belgium and Italy. In contrast, French specimens suggest an independent introduction event of squirrels originating from Asia. 相似文献
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The simulation model SIDRA is based on a semi-analytical and semi-numerical solution to the Boussinesq equation. It has been developed on the ground of theoretical and field experimental results with the aim of a good prediction of both drainage peak and recession flow rates. Theoretical aspects and basic equations of the model are presented for the most general case where both soil physical properties and water table shapes are depth-dependent. The parameter sensitivity and field performances of the model are estimated in shallow loamy soils facing a seasonal waterlogging during winter season in France. Water table shape factors are the most sensitive parameters. Drainable porosity is slightly more sensitive than hydraulic conductivity for drainflow rate prediction whereas hydraulic conductivity is slightly more sensitive for water table elevation prediction. A comparison of experimental and simulated long term discharge and water table exceedance duration curves shows that the model could be a useful tool to assess the performances and control the relevance of a given subsurface drainage design.
Résumé Le modèle de simulation SIDRA est basé sur une résolution semi-analytique et semi-numérique de l'équation de Boussinesq. Il a été développé à partir d'une approche théorique et de l'analyse de résultats d'expérimentations de terrain avec pour principal objectif d'atteindre une bonne prédiction des débits de pointe et de tarissement. Les principales équations du modèles sont présentées dans leur forme la plus générale qui permet de prendre en compte des propriétés hydrodynamiques et des formes de nappe dépendantes de la profondeur. L'étude de sensibilité aux paramètres et l'évaluation des performances du modèle sont réalisées dans le cas de sols limoneux peu profonds, sur la période hivernale où se manifeste l'engorgement des sols en France. Le modèle est très sensible aux variations des facteurs de forme de nappe. Concernant les paramètres hydrodynamiques, les débits simulés sont plus sensibles aux variations de la porosité de drainage qu'à celles de la conductivité hydraulique. A l'inverse les hauteurs de nappe simulées sont plus sensibles aux variations de conductivité hydraulique. Une comparaison sur une longue période des fréquences de dépassement de débits et hauteurs de nappe, simulées et observées, montre que le modèle peut constituer un bon outil de contrôle de l'efficacité d'un réseau de drainage et de son dimensionnement.相似文献
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P Delatour M P Tiberghien F Garnier E Beno?t 《American journal of veterinary research》1985,46(6):1399-1402
The pharmacokinetics of febantel and its main metabolites were studied in cattle and sheep. Seven ewes and 4 heifers were given febantel orally in a single dose of 7.5 mg/kg, 25 mg/kg, or 45 mg/kg of body weight. Plasma concentrations vs time of febantel and individual metabolites were determined by high-performance liquid chromatography analysis. Intestinal absorption of febantel was faster and biotransformations were more active in sheep than in cattle. 相似文献
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Characterizing historical(1992–2010) transitions between grassland and cropland in mainland France through mining land-cover survey data 
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下载免费PDF全文 Grassland, as one of the largest ecosystems on the earth, supports various goods and services to humanity.Historically, humans have increased agricultural output primarily by cropland expansion and agricultural intensification.The cropland area was primarily gained at the expense of grassland and forests.Apart from grassland conversion, increasing consumption of calorie- and meat-intensive diets drives the intensification of livestock systems, which is shifting steadily from grazing to feeding with crops.To cope with the environmental degradation due to agriculture, various forms of ‘green payment' were implemented to promote the adoption of sustainable farming practices over the last two decades in the European Union.The aim of this study is to monitor the recent transitions(1992–2010) between grassland and cropland during two Common Agricultural Policy(CAP) reforms at the French mainland scale.We proposed an innovative approach to link grassland conversion to agricultural commodities and farming systems practices.We first assessed the grassland-to-cropland conversion and further investigated the crop sequence patterns that were observed to be dominant after the conversion through mining land-cover survey data Teruti and Teruti-Lucas.We found the trends of the transitions between grassland and cropland over the two time intervals: The loss of grassland(1992–2003) and restoration or re-expansion of grassland(2006–2010) in mainland France.Our finding on the crop sequence patterns after the grassland conversion reveals two notable evolutions of agricultural production systems.These evolutions were related to the increase in the proportion of cropland in the total agricultural land use.One evolution was most likely influenced by the demand for fodder: The conversion from grazing livestock to feeding livestock.Another evolution was the conversion from livestock production to field crop production.Our results indicate that the intensification of livestock farming systems continued over the last two decades in France.We conclude that, the approach developed in this study can be considered as a generic method for monitoring the transitions between grassland and cropland and further identifying the crop sequence patterns after the grassland conversion from time-series land cover data. 相似文献
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Samuel Dufour-Kowalski Benoît Courbaud Philippe Dreyfus Céline Meredieu François de Coligny 《Annals of Forest Science》2012,69(2):221-233