Mississippi (fleuve)

Résumé

Le Mississippi (Mississippi River) est un fleuve d’Amérique du Nord qui traverse la partie centrale des États-Unis. Il coule du Nord du Minnesota au golfe du Mexique et son cours a une orientation méridienne. Le Mississippi a une longueur de : seul l'un de ses affluents, le Missouri, est plus long en Amérique du Nord. La superficie du bassin versant fait du Mississippi l'un des fleuves les plus importants du monde et du Missouri-Mississippi l'un des bassins fluviaux les plus grands du monde. Pendant l'époque précolombienne, le Mississippi constitue déjà une voie de navigation dont le cours supérieur est appelé par les Ojibwés misi-ziibi, qui signifie « grand fleuve », repris en 1666 en français sous la forme Messipi. Supervisé par la Mississippi Valley Division et une commission fédérale créée en 1879, le fleuve reste encore aujourd'hui un élément fondamental de l'économie et de la culture des États-Unis. Si on compare le Mississippi et le Missouri, de leur source à leur confluence

Source officielle

https://fr.wikipedia.org/wiki/Mississippi_(fleuve)

À propos de ce résultat

Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Publications associées (4)

Publications associées

Chargement

Personnes associées (2)

Personnes associées

Chargement

Unités associées (1)

Unités associées

Chargement

Concepts associés (78)

Concepts associés

Chargement

Cours associés (10)

Stream and river ecosystems are increasingly deteriorated owing to global change and climate change. Students will understand basic physical, chemical and biological processes in streams and rivers, and how they relate to ecosystem health and integrity .

Water resources engineering designs systems to control the quantity, quality, timing, and distribution of water to support human demands and the needs of the environment.

"Hydrology for Engineers" is an introduction to the study of floods, droughts and a fair distribution of water. The course will introduce basic hydrologic concepts and methods: probability and statistics, surface and subsurface hydrological processes

Afficher plus

Cours associés

Chargement

Séances de cours associées (13)

Afficher plus

Séances de cours associées

Chargement

Metapopulation persistence and species spread in river networks

Enrico Bertuzzo, Marino Gatto, Lorenzo Mari, Andrea Rinaldo

River networks define ecological corridors characterised by unidirectional streamflow, which may impose downstream drift to aquatic organisms or affect their movement. Animals and plants manage to persist in riverine ecosystems, though, which in fact harbour high biological diversity. Here, we study metapopulation persistence in river networks analysing stage-structured populations that exploit different dispersal pathways, both along-stream and overland. Using stability analysis, we derive a novel criterion for metapopulation persistence in arbitrarily complex landscapes described as spatial networks. We show how dendritic geometry and overland dispersal can promote population persistence, and that their synergism provides an explanation of the so-called `drift paradox'. We also study the geography of the initial spread of a species and place it in the context of biological invasions. Applications concerning the persistence of stream salamanders in the Shenandoah river, and the spread of two invasive species in the Mississippi-Missouri are also discussed.

Wiley-Blackwell2014

Chargement

, , ,

We propose a novel ecohydrological model for the invasion of inland waters by the zebra mussel Dreissena polymorpha and test it against field data gathered within the Mississippi-Missouri river system in North America. This biological invasion poses major ecological and economic threats, especially due to the huge population densities reached by local zebra mussel colonies and the species' unparalleled dispersal abilities within fluvial systems. We focus on a quantitative evaluation, attempted here for the first time, of the individual roles and the mutual interactions of drivers and controls of the Mississippi-Missouri invasion. To this end, we use a multilayer network model accounting explicitly for zebra mussel demographic dynamics, hydrologic transport, and dispersal due to anthropic activities. By testing our results against observations, we show that hydrologic transport alone is not sufficient to explain the spread of the species at the basin scale. We also quantify the role played by commercial navigation in promoting the initial, selective colonization of the river system, and show how recreational boating may have determined the capillary penetration of the species into the water system. The role of post-establishment dispersal mechanisms and the effectiveness of possible prevention measures are also discussed in the context of model sensitivity and robustness to reparametrization.

American Geophysical Union2011

Chargement

On the geographic range of freshwater ﬁsh in river basins

Enrico Bertuzzo, Andrea Rinaldo

We study the observed geographic distribution of freshwater fish species in the Mississippi-Missouri river system, focusing on the size and spatial distribution of geographic ranges. We use a particular metric of geographic distribution known as environmental resistance, a biogeographic index that quantifies the pointwise average spatial loss of community similarity to identify biogeographic regions of the river basin. Empirical patterns are compared with the results of a neutral metacommunity model in which local fish communities are interconnected through the ecological corridors provided by the river networks. Because neutral theory assumes that all individuals across all the species are functionally equivalent, the comparison is aimed to quantify how much of the geographic range patterns are the result of species' similarity rather than species differences, thus searching for an ecological null model for the analysis of biogeographic range. We also analyze how river network topology affects the spatial arrangement of species. Our results suggest that broad patterns of geographic range of freshwater fish in the Mississippi-Missouri can be explained simply by neutral dynamics engaged in river topology and competition for resources among species without invoking mechanisms that involve asymmetric interspecific interactions.

American Geophysical Union2009

Chargement