Download or read book tude de la variabilit spatio temporelle des apports d eau douce dans la baie James written by Rémi Costanzo and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: « Le débit des rivières de la baie James a été affecté non seulement par les changements climatiques, mais aussi par les dérivations de bassins versants qui ont augmentées artificiellement le débit de la Grande Rivière à des fins de production hydro-électrique. Le but de cette recherche est de décrire la variabilité spatio-temporelle du débit annuel de ruissellement à la baie James en utilisant les données de modélisation de ERA5 de 1951 à 2020. La somme des débits annuels de précipitations et d’évaporation a permis de modéliser le débit de ruissellement par année hydrologique (octobre à septembre). La validation du modèle avec les données de stations hydrométriques présentes dans la zone d’étude a démontré qu’une calibration préalable était nécessaire. Les données calibrées ont été comparées aux valeurs des stations et ne montrent pas de différences significatives (test de rangs signés de Wilcoxon; p = 0.769). Le débit des rivières et les précipitations nettes sur le bassin versant de la baie James ont augmenté significativement de 0.88 km3/an2 (soit 0.25 % par an) entre 1951 et 2020. Toutefois, cette hausse est principalement causée par la dérivation de la partie amont de la rivière Caniapiscau. En l’absence des dérivations, la hausse n’aurait été que de 0.27 km3/an2 (valeur non significative). Sur cette période, aussi bien les précipitations que l’évaporation ont augmenté de manière significative. Le ruissellement, les précipitations et l’évaporation ont diminué à la baie James entre 1951 et 1976 et ont ensuite augmenté rapidement de 1976 à 2020. Le débit annuel des rivières du nord-est de la baie James a augmenté suite aux dérivations successivement de 69.38 km3/an (moyenne pour 1951-1978) à 116.28 km3/an (moyenne pour 1985-2009) après les dérivations des rivières Caniapiscau, Grande rivière de la Baleine et Eastmain, puis à 145.12 km3/an (moyenne pour 2010-2020) après la dérivation de la rivière Rupert. Entre 1951 et 2020, la baie James a reçu, en moyenne, 133.9 km3/an d’eau douce de sa rive ouest et 180.0 km3/an (excluant l’effet des dérivations) ou 192.3 km3/an (incluant les dérivations) de sa rive est. Cette étude présente une nouvelle façon d’estimer les débits annuels de ruissellement permettant une meilleure vue globale du cycle de l’eau douce de la baie James à long terme, ce qui permettra d’affiner nos connaissances océanographiques de cette région. -- Mot(s) clé(s) en français : Mots clés : baie James, débit annuel, rivières, dérivation de rivière, ERA5, évaporation, précipitations, modélisation, eau douce, hydrologie. »--
Download or read book Etude des caract ristiques physiques et physico chimiques de l panchement et du m lange d eau douce de la Grande Rivi re dans la Baie James en t written by and published by . This book was released on 1983 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book tude de la variation spatio temporelle de la temp rature de surface de l eau dans le Golfe du Saint Laurent l aide d images satellitaires infrarouges written by Pascal Guillot and published by . This book was released on 2001 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Baie james complexe nbr written by Pierre Dumas and published by . This book was released on 1972 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Le Golfe Du Saint Laurent petit Oc an Ou Grand Estuaire written by Canada. Department of Fisheries and Oceans and published by Peches Et Oceans Direction Generale Des Communications = Fisheries and Oceans Communications Dir. This book was released on 1991 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of a workshop, the scientific reviews and the contributed papers presented at the symposium. The document presents a brief historical summary of marine research in the Gulf; reports the discussions, conclusions and recommendations of the different working groups on oceanography (physics, biology, chemistry and sedimentology) and on the fishery (fish and invertebrates); then presents the discussions of each multidisciplinary working group, centered around how the St. Lawrence system may be used as a natural laboratory which will contribute to the solution of major long-term problems of conservation of natural resources and of the quality of the environment.
Download or read book Greenhouse Gas Emissions Fluxes and Processes written by A. Tremblay and published by Springer Science & Business Media. This book was released on 2011-04-30 with total page 743 pages. Available in PDF, EPUB and Kindle. Book excerpt: In a time when an unquestionable link between anthropogenic emissions of greenhouse gases and climatic changes has finally been acknowledged and * widely documented through IPCC reports, the need for precise estimates of greenhouse gas (GHG) production rates and emissions from natural as well as managed ecosystems has risen to a critical level. Future agreements between nations concerning the reduction of their GHG emissions will - pend upon precise estimates of the present level of these emissions in both natural and managed terrestrial and aquatic environments. From this viewpoint, the present volume should prove to a benchmark contribution because it provides very carefully assessed values for GHG emissions or exchanges between critical climatic zones in aquatic en- ronments and the atmosphere. It also provides unique information on the biases of different measurement methods that may account for some of the contradictory results that have been published recently in the literature on this subject. Not only has a large array of current measurement methods been tested concurrently here, but a few new approaches have also been developed, notably laser measurements of atmospheric CO concentration 2 gradients. Another highly useful feature of this book is the addition of - nitoring and process studies as well as modeling.
Download or read book Le Pacifique Sud written by Frédéric Angleviel and published by Presses Univ de Bordeaux. This book was released on 1991 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ecosystem Function in Heterogeneous Landscapes written by Gary M. Lovett and published by Springer Science & Business Media. This book was released on 2005-12-15 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: This groundbreaking work connects the knowledge of system function developed in ecosystem ecology with landscape ecology's knowledge of spatial structure. The book elucidates the challenges faced by ecosystem scientists working in spatially heterogeneous systems, relevant conceptual approaches used in other disciplines and in different ecosystem types, and the importance of spatial heterogeneity in conservation resource management.
Download or read book Nitrogen Cycling in Coastal Marine Environments written by T. Henry Blackburn and published by . This book was released on 1988-03-21 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrogen discharge to the coastal environment has been increasing, posing the threat of accelerated eutrofication. Considerable research has been conducted in recent years to examine the impact of the nitrogen loading in coastal ecosystems. Based on proceedings from a SCOPE symposium held at the University of Aarhus in July of 1985, this volume covers a variety of up-to-date developments in research on nitrogen cycling in coastal marine environments. Topics include the role of nitrogen in algal productivity, regeneration of nutrients in the water column and the sediments, and the flow of nitrogen in coastal ecosystems.
Download or read book Global Versus Local Changes in Upwelling Systems written by Marie-Hélène Durand and published by IRD Orstom. This book was released on 1998 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heritage Sites of Astronomy and Archaeoastronomy in the Context of the UNESCO World Heritage Convention written by Clive L. N. Ruggles and published by . This book was released on 2017-11-30 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt: This joint venture between ICOMOS, the advisory body to UNESCO on cultural sites, and the International Astronomical Union is the second volume in an ongoing exploration of themes and issues relating to astronomical heritage in particular and to science and technology heritage in general. It examines a number of key questions relating to astronomical heritage sites and their potential recognition as World Heritage, attempting to identify what might constitute "outstanding universal value" in relation to astronomy. "Heritage Sites of Astronomy and Archaeoastronomy--Volume 2" represents the culmination of several years' work to address some of the most challenging issues raised in the first ICOMOS-IAU Thematic Study, published in 2010. These include the recognition and preservation of the value of dark skies at both cultural and natural sites and landscapes; balancing archaeoastronomical considerations in the context of broader archaeological and cultural values; the potential for serial nominations; and management issues such as preserving the integrity of astronomical sightlines through the landscape.Its case studies are developed in greater depth than those in volume 1, and generally structured as segments of draft nomination dossiers. They include seven-stone antas (prehistoric dolmens) in Portugal and Spain, the thirteen towers of Chankillo in Peru, the astronomical timing of irrigation in Oman, Pic du Midi de Bigorre Observatory in France, Baikonur Cosmodrome in Kazakhstan, and Aoraki-Mackenzie International Dark Sky Reserve in New Zealand. A case study on Stonehenge, already a World Heritage Site, focuses on preserving the integrity of the solstitial sightlines.As for the first ICOMOS-IAU Thematic Study, a international team of authors including historians, astronomers and heritage professionals is led by Professor Clive Ruggles for the IAU and Professor Michel Cotte for ICOMOS.
Download or read book The Last Billion Years written by Atlantic Geoscience Society and published by Nimbus Publishing (CN). This book was released on 2001 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is about the history of the rocks and fossils of the Maritime Provinces of Canada (New Brunswick, Nova Scotia and PEI) over the last billion years. The book is beautifully illustrated in full colour, with original paintings of ancient vistas, over 150 photographs, and crisp explanatory diagrams and sketches.
Download or read book The Biogeochemistry of Mercury in the Environment written by Jerome O. Nriagu and published by Elsevier-North-Holland Biomedical Press. This book was released on 1979 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lake Chilwa written by M. Kalk and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 444 pages. Available in PDF, EPUB and Kindle. Book excerpt: Leonard C. Beadle In contrast to the more sta bie oceans, inland waters are, on the geological time scale, short-lived and are subject to great fluctuations in chemical composition and physical features. Very few lakes and rivers have existed continuously for more than a million years, and the life of the majority is to be measured in thousands or less. Earth movements, erosion and long-term climatic changes in the past have caused many of them to appear and disappear. No wonder then that most freshwater organism are especially adapted to great changes and many even to temporary extinction of their environment. Recent studies of residual sediments from existing and extinct lakes in tropical Africa have told us much about their age and the past history of their faunas and floras, from which we may deduce something about the climate and the conditions in the water in the past. The forces that have formed and moulded the African Great Lakes have been catastrophic in their violence and effects. They are not yet finished, but the present rate of change is, in human terms, too slow for direct observation of the ecological effects. The large man-made lakes are providing very good opportunities for studying the chemi cal and biological consequences of the initial filling but, once filled, they are artificially protected against major fluctuations.
Download or read book Water Heritage written by Willem Willems and published by . This book was released on 2017-01-15 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: Water is vital for life, and its availability has been a concern for mankind throughout the ages. Its presence has always been ascertained in a variety of ways and the development of human society everywhere is connected with various forms of water management. Man also needed to manage water to find protection from its dangers and the need for that is increasing. In the coming decades, the impact of climate change is expected to intensify floods and droughts, affect groundwater resources, raise sea levels, increase pollution and enhance the frequency and magnitude of disasters. Societies around the world are challenged to adapt to these threats to ensure water security, economic prosperity and environmental and cultural sustainability. This book deals with the heritage of water management and the use that was made of water, as well as the impact of water management on heritage. An example of the former may be an ancient irrigation system in the Filipines or in the Middle East that still functions today, while the latter may reflect the importance of maintaining groundwater levels for the preservation of organic remains on archaeological sites or of wooden piles underneath standing buildings. In either case the papers in this book reflect the dynamic nature of water, and hence the equally dynamic relation between water management and heritage. This publication follows up on a Heritage and Water conference in Amsterdam, the first of its kind. Its main purpose is to credibly present the importance and value of heritage and historical experience for water and sustainable development, and vice versa, present the importance of water management for the protection of heritage. It presents evolving insights and concepts about Water and about Heritage from a variety of disciplines, policy and public perspectives illustrated with cases studies and aims to connect decision makers with experts such as engineers, archaeologists, historians, geographers, ecologist and landscape architects
Download or read book The Rehabilitation of the Delta of the Senegal River in Mauritania written by Olivier Hamerlynck and published by IUCN. This book was released on 2003 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book South African Red Data Book written by Paul Harvey Skelton and published by . This book was released on 1987 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
