27 results on '"*PHYSICAL geography"'
Search Results
2. Nothing New under the Sun? George Perkins Marsh and Roots of U.S. Physical Geography.
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Bendix, Jacob and Urban, Michael A.
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PHYSICAL geography , *ENVIRONMENTAL history , *HUMAN ecology , *ANTHROPOGENIC effects on nature - Abstract
U.S. geomorphologists and biogeographers often cite early theoretical roots dating back to late nineteenth- and early twentieth-century exemplars such as Powell, Gilbert, Cowles, and Clements, or earlier European contributors like Hutton, Lyell, von Humboldt, and, of course, Darwin. Yet reviews of our intellectual roots often overlook an early and important U.S. contributor: George Perkins Marsh. Marsh's work on Man and Nature is more often cited in the field of environmental history, where it is appropriately noted as a prescient review of human impacts on the landscape. We suggest, however, that his significance extends beyond early environmental activism and that in fact Marsh describes many concepts and analytical approaches that continue to underlie modern geomorphology and biogeography. Moreover, Marsh's ideas and approach presaged fundamental concepts central to our current study of the Anthropocene and coupled human–environment systems, as he emphasized interconnections among biotic, geomorphic and human elements, perhaps most notably with regard to impacts of deforestation on flood regimes. There is, therefore, much to learn from Marsh—both about early thinking in physical geography and about the depth of scientific analysis underlying our discipline's early interest in human impacts. [ABSTRACT FROM AUTHOR]
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- 2021
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3. Introduction to the special issue on necrogeography and physical geography.
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Thornbush, M. J.
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PHYSICAL geography , *CEMETERIES , *GEOMORPHOLOGY - Abstract
In this introduction to the special issue on necrogeography and physical geography, a focus on landforms and landscapes is presented and applied to subdisciplinary areas, including geomorphology, climatology, biogeography, and soil science. The primary aim is to present past directions taken in the field by physical geographers and provide further areas for their potential engagement. The seven papers contained in this special issue are lastly conveyed in terms of their contribution to necrogeography as an applied physical geography in cemeteries, although not exclusively. [ABSTRACT FROM AUTHOR]
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- 2018
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4. Physical geography in the Anthropocene.
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Ellis, Erle C.
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PHYSICAL geography , *EFFECT of human beings on climate change , *GEOLOGICAL time scales , *ANTHROPOCENE Epoch , *PHYSICAL geographers - Abstract
Even as it remains an informal term defining the emergence of humans as a force transforming Earth as a system, the Anthropocene is stimulating novel research and discussion across the academy and well beyond. While geography has always been deeply connected with the coupled human--environment paradigm, physical geographer's embrace of the Anthropocene still appears lukewarm at best. While there are good reasons to hesitate, including the fact that the Anthropocene is not yet, and might never be, formalized in the Geologic Time Scale, physical geographers have much to gain by embracing what is rapidly becoming the most influential scholarly discussion on human--environmental relations in a generation. This editorial was commissioned for the author's debut as Contributing Editor of Progress in Physical Geography. [ABSTRACT FROM AUTHOR]
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- 2017
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5. A Geographic Overview of Panama : Pathway to the Continents and Link between the Seas
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Palka, Eugene J., Singh, V. P., editor, and Harmon, Russell S., editor
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- 2005
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6. Towards a strategy for Critical Zone science in Canada.
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Martin, Yvonne E. and Johnson, E. A.
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GEOMORPHOLOGY , *CLIMATOLOGY , *ENVIRONMENTAL research , *HYDROLOGY , *BIOGEOGRAPHY - Abstract
The Critical Zone is an interdisciplinary theme for environmental research that considers the near surface environment of the Earth and interactions amongst rock, soil, water, air, and living organisms. Critical Zone research initiatives in the United States (US) have met with great success, with multiple Critical Zone Observatories located in a variety of regional field settings at their core. These initiatives have allowed for enormous advances in addressing interdisciplinary environmental science questions based on team collaborations involving experts from various disciplines. The Critical Zone initiative in the US is now being extended to several other countries, but Canada has not been a participant in initial meetings involving various national funding agencies and researchers from different countries. Because physical geographers study a wide range of topics falling under the banner of Critical Zone science (including soils, hydrology, geomorphology, climatology, glaciology, biogeography), they are well poised to be active participants in national strategies for Critical Zone science. Suggestions are provided for moving towards a national strategy for Critical Zone science initiatives in Canada that connect to recent international developments. Vers une stratégie pour la science de la zone critique au Canada La zone critique est un thème interdisciplinaire de la recherche environnementale qui examine le milieu de la proche surface de la Terre et les interactions entre la roche, le sol, l'eau, l'air et les organismes vivants. Les initiatives de recherche en zone critique aux États-Unis ont connu beaucoup de succès grâce à de nombreux observatoires de la zone critique situés au centre de divers dispositifs d'études régionales. Ces initiatives ont permis d'accomplir d'énormes progrès en abordant des questions de science environnementale interdisciplinaire fondées sur la collaboration d'équipes impliquant des spécialistes de diverses disciplines. Les initiatives américaines en zone critique sont maintenant étendues à de nombreux autres pays, mais le Canada n'a pas participé aux premières réunions impliquant divers organismes nationaux de financement ainsi que des chercheurs de différents pays. Comme les géographes spécialisés en géographie physique étudient un large éventail de thèmes placés sous la bannière de la science de la zone critique (y compris les sols, l'hydrologie, la géomorphologie, la climatologie, la glaciologie, la biogéographie), ils sont bien placés pour participer activement aux stratégies nationales pour la science de la zone critique. Des suggestions sont faites dans le but d'adopter une stratégie nationale pour les initiatives concernant la science de la zone critique au Canada qui se rattachent aux récents progrès internationaux. [ABSTRACT FROM AUTHOR]
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- 2017
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7. La géographie physique des vingt-cinq dernières années en France. Etat des lieux
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Yvette Veyret
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physical geography ,geomorphology ,biogeography ,climatology ,hydrology ,environment ,Geography (General) ,G1-922 - Abstract
Physical geography has evolved a lot in France during the last twenty-five years. Geomorphology, a long time dominant, shares from now on its place with biogeography, climatology and hydrology. Today physical geography is largely approached as a whole, in interrelationship with the social phenomena, the policies of national development, the history of society. The reorientation of geography is visible.This evolution, which took place with difficulty in the 1980s, was due in particular to biogeographer Georges Bertrand and geomorphologist Jean Tricart. Physical geography is from now on integrated into the questions of national development, by means of resources (water, energy...), constraints, and risks, but also landscapes and patrimony. It implies in-depth knowledge of the working of the planet, and of the present processes characterizing ground surface, vegetation covers, climates, water and heritages. The role of societies in the evoked dynamics is important to define, and the impact of the environment on societies is also to consider. This « reoriented » physical geography which can, consequently, be defined in terms of environment or « geoenvironnement », must find its place beside ecology, whose opening in the French media dates back to the 1980s. Society is the main item of geographical analysis, as people living in the nature use it and sometimes damage it. Nevertheless geography and its environmental dimension do not consider man a systematic destroyer of nature. They reject any systematically pessimistic or backward-looking speech, and underline, by means of a rigorous analysis of the interrelationships nature/society, the need to establish sound diagnoses as for the state of the environment and the actions of societies on the environment.
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- 2003
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8. A Hierarchical Classification of Benthic Biodiversity and Assessment of Protected Areas in the Southern Ocean.
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Douglass, Lucinda L., Turner, Joel, Grantham, Hedley S., Kaiser, Stefanie, Constable, Andrew, Nicoll, Rob, Raymond, Ben, Post, Alexandra, Brandt, Angelika, and Beaver, Daniel
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BIODIVERSITY , *MARINE parks & reserves , *CONSERVATION biology , *BIOGEOGRAPHY ,ENVIRONMENTAL protection planning - Abstract
An international effort is underway to establish a representative system of marine protected areas (MPAs) in the Southern Ocean to help provide for the long-term conservation of marine biodiversity in the region. Important to this undertaking is knowledge of the distribution of benthic assemblages. Here, our aim is to identify the areas where benthic marine assemblages are likely to differ from each other in the Southern Ocean including near-shore Antarctica. We achieve this by using a hierarchical spatial classification of ecoregions, bathomes and environmental types. Ecoregions are defined according to available data on biogeographic patterns and environmental drivers on dispersal. Bathomes are identified according to depth strata defined by species distributions. Environmental types are uniquely classified according to the geomorphic features found within the bathomes in each ecoregion. We identified 23 ecoregions and nine bathomes. From a set of 28 types of geomorphic features of the seabed, 562 unique environmental types were classified for the Southern Ocean. We applied the environmental types as surrogates of different assemblages of biodiversity to assess the representativeness of existing MPAs. We found that 12 ecoregions are not represented in MPAs and that no ecoregion has their full range of environmental types represented in MPAs. Current MPA planning processes, if implemented, will substantially increase the representation of environmental types particularly within 8 ecoregions. To meet internationally agreed conservation goals, additional MPAs will be needed. To assist with this process, we identified 107 spatially restricted environmental types, which should be considered for inclusion in future MPAs. Detailed supplementary data including a spatial dataset are provided. [ABSTRACT FROM AUTHOR]
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- 2014
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9. The composite nature of physical geography: Moving from linkages to integration.
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Malanson, George P., Scuderi, Louis, Moser, Katrina A., Willmott, Cort J., Resler, Lynn M., Warner, Timothy A., and Mearns, Linda O.
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PHYSICAL geography , *MANUSCRIPTS , *COASTAL changes , *DISCUSSION - Abstract
This editorial is the product of the Progress in Physical Geography lecture at the April 2013 meeting of the Association of American Geographers. The paper was presented by George Malanson, the North American Editor, and the co-authors presented critiques based on a draft. Subsequently, the manuscript was developed and revised based on discussion at the meeting and additional exchange among the co-authors. [ABSTRACT FROM AUTHOR]
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- 2014
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10. On early-Holocene moisture and small-mammal histories in the Bonneville basin, Western United States
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Dave N. Schmitt and Karen D. Lupo
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010506 paleontology ,Archeology ,Global and Planetary Change ,geography ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,Ecology ,Moisture ,Biogeography ,fungi ,Paleontology ,Small mammal ,Structural basin ,01 natural sciences ,humanities ,Cave ,Physical geography ,Geomorphology ,Groundwater ,Rock shelter ,Holocene ,Geology ,0105 earth and related environmental sciences ,Earth-Surface Processes - Abstract
Comparisons of Bonneville basin small-mammal skeletal assemblages from low-elevation caves with a collection from an upper piedmont rock shelter support Oviatt et al.’s hypothesis that early-Holoce...
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- 2017
11. Soil moisture: A central and unifying theme in physical geography.
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Legates, David R., Mahmood, Rezaul, Levia, Delphis F., DeLiberty, Tracy L., Quiring, Steven M., Houser, Chris, and Nelson, Frederick E.
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SOIL moisture , *PHYSICAL geography , *SURFACE of the earth , *WEATHERING , *SEDIMENT transport , *BIOGEOGRAPHY , *GEOMORPHOLOGY - Abstract
Soil moisture is a critical component of the earth system and plays an integrative role among the various subfields of physical geography. This paper highlights not just how soil moisture affects atmospheric, geomorphic, hydrologic, and biologic processes but that it lies at the intersection of these areas of scientific inquiry. Soil moisture impacts earth surface processes in such a way that it creates an obvious synergistic relationship among the various subfields of physical geography. The dispersive and cohesive properties of soil moisture also make it an important variable in regional and microclimatic analyses, landscape denudation and change through weathering, runoff generation and partitioning, mass wasting, and sediment transport. Thus, this paper serves as a call to use research in soil moisture as an integrative and unifying theme in physical geography. [ABSTRACT FROM AUTHOR]
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- 2011
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12. Büdel, J. 1982: Climatic geomorphology. Princeton: Princeton University Press. (Translation of Klima-geomorphologie, Berlin-Stuttgart: Gebrüder Borntraeger, 1977.).
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Migon, Piotr
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CLIMATIC geomorphology , *GEOMORPHOLOGY , *PHYSICAL geography , *BOOKS , *BIOGEOGRAPHY , *GEOGRAPHY , *PHYSICAL sciences - Abstract
The article comments on the book "Climatic Geomorphology," by Julius Budel. It is a translation of the German book from 1977 "Klima-geomorphologie," Berlin-Stuttgart: Gebruder Borntraeger. For a mathematically skilled and modelling-orientated present-day geomorphologist hungry for numerical values and increasingly sophisticated software, it would be tempting to dismiss the book altogether as a long outdated which did not stand the test of time and does not meet recent criteria for evaluation. It is, however, true that Büdel's book abounds in bold, authoritarian statements and its many sections suffer from an unnecessary either/or approach in which Budel was right and other people were wrong.
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- 2006
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13. Coastal geomorphology.
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Stephenson, Wayne J.
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GEOMORPHOLOGY , *PHYSICAL geography , *GEOGRAPHY , *EARTH sciences , *COSMOGRAPHY , *WORLD history , *BIOGEOGRAPHY , *PHYSICAL sciences - Abstract
The article discusses issues related coastal geomorphology in the U.S. It should be noted that there continues to be a clear trend away from the centrality of geomorphology and geography. It even appears that coastal geomorphologists are no longer publishing in major geomorphology journals. There is little evidence to suggest that coastal geomorphology is making significant contributions to the broader theoretical framework of geomorphology. The author offers some commentary on the position of coastal geomorphology within Geomorphology and Physical Geography, based on the progress made over the last three years.
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- 2006
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14. Aridity drives plant biogeographical sub regions in the Caatinga, the largest tropical dry forest and woodland block in South America
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Augusto C. Silva and Alexandre F. Souza
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0106 biological sciences ,0301 basic medicine ,Atmospheric Science ,Topography ,lcsh:Medicine ,Woodland ,Forests ,01 natural sciences ,Mountains ,Aridity index ,lcsh:Science ,Climatology ,Multidisciplinary ,Geography ,Ecology ,Eukaryota ,Last Glacial Maximum ,Plants ,Terrestrial Environments ,Droughts ,Phylogeography ,Biogeography ,Research Article ,Tropical and subtropical dry broadleaf forests ,Ecological Metrics ,Forest Ecology ,010603 evolutionary biology ,Ecosystems ,03 medical and health sciences ,Paleobotany ,Paleoclimatology ,Endemism ,Spatial Analysis ,Tropical Climate ,Landforms ,Plant Dispersal ,Ecology and Environmental Sciences ,lcsh:R ,Organisms ,Biology and Life Sciences ,Paleontology ,Species diversity ,Geomorphology ,Species Diversity ,South America ,Arid ,Index of dissimilarity ,Logistic Models ,030104 developmental biology ,Earth Sciences ,lcsh:Q ,Physical geography ,Paleobiology - Abstract
Our aims were to quantify and map the plant sub regions of the the Caatinga, that covers 844,453 km2 and is the largest block of seasonally dry forest in South America. We performed spatial analyses of the largest dataset of woody plant distributions in this region assembled to date (of 2,666 shrub and tree species; 260 localities), compared these distributions with the current phytogeographic regionalizations, and investigated the potential environmental drivers of the floristic patterns in these sub regions. Phytogeographical regions were identified using quantitative analyses of species turnover calculated as Simpson dissimilarity index. We applied an interpolation method to map NMDS axes of compositional variation over the entire extent of the Caatinga, and then classified the compositional dissimilarity according to the number of biogeographical sub regions identified a priori using k-means analysis. We used multinomial logistic regression models to investigate the influence of contemporary climatic productivity, topographic complexity, soil characteristics, climate stability since the last glacial maximum, and the human footprint in explaining the identified sub regions. We identified nine spatially cohesive biogeographical sub regions. Current productivity, as indicated by an aridity index, was the only explanatory variable retained in the best model, explaining nearly half of the floristic variability between sub regions. The highest rates of endemism within the Caatinga were in the Core and Periphery Chapada Diamantina sub regions. Our findings suggest that the topographic complexity, soil variation, and human footprint in the Caatinga act on woody plant distributions at local scales and not as determinants of broad floristic patterns. The lack of effect of climatic stability since the last glacial maximum probably results from the fact that a single measure of climatic stability does not adequately capture the highly dynamic climatic shifts the region suffered during the Pleistocene. There was limited overlap between our results and previous Caatinga classifications.
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- 2018
15. Vegetation Controls on Weathering Intensity during the Last Deglacial Transition in Southeast Africa
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Anne-Marie Lézine, Annie Vincens, Michael M. McGlue, Andrew S. Cohen, Sarah J. Ivory, Geoffrey S. Ellis, Brown University, University of Kentucky, United States Geological Survey [Reston] (USGS), Biogéochimie-Traceurs-Paléoclimat (BTP), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of Arizona, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), University of Kentucky (UK), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN), and Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA)
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Geologic Sediments ,Malawi ,010504 meteorology & atmospheric sciences ,Rain ,lcsh:Medicine ,Marine and Aquatic Sciences ,Limnogeology ,Woodland ,010502 geochemistry & geophysics ,01 natural sciences ,CARBON-DIOXIDE ,X-Ray Diffraction ,Global Change Ecology ,Tropical climate ,Dry season ,Limnology ,lcsh:Science ,Kaolin ,History, Ancient ,Sedimentary Geology ,Multidisciplinary ,CLIMATE-CHANGE ,Geography ,Ecology ,[SDE.IE]Environmental Sciences/Environmental Engineering ,POLLEN ,Geology ,Vegetation ,Biodiversity ,TANZANIA ,Biogeography ,Erosion ,Aluminum Silicates ,Research Article ,LAKE MALAWI ,Forest Ecology ,TROPICAL EAST-AFRICA ,Climate Change ,[SDE.MCG]Environmental Sciences/Global Changes ,Climate change ,TANGANYIKA ,Biology ,Species Specificity ,Paleoclimatology ,Deglaciation ,Paleobotany ,GLACIAL MAXIMUM ,Younger Dryas ,Paleolimnology ,Particle Size ,Terrestrial Ecology ,Plant Physiological Phenomena ,0105 earth and related environmental sciences ,Tropical Climate ,LATE QUATERNARY ,Silicates ,lcsh:R ,Ecology and Environmental Sciences ,Biology and Life Sciences ,Paleontology ,Geomorphology ,15. Life on land ,[SDE.ES]Environmental Sciences/Environmental and Society ,Lakes ,13. Climate action ,RAINFALL SEASONALITY ,Earth Sciences ,Clay ,lcsh:Q ,Physical geography ,Paleoecology ,Paleobiology ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology - Abstract
International audience; Tropical climate is rapidly changing, but the effects of these changes on the geosphere are unknown, despite a likelihood of climatically-induced changes on weathering and erosion. The lack of long, continuous paleo-records prevents an examination of terrestrial responses to climate change with sufficient detail to answer questions about how systems behaved in the past and may alter in the future. We use high-resolution records of pollen, clay mineralogy, and particle size from a drill core from Lake Malawi, southeast Africa, to examine atmosphere-biosphere-geosphere interactions during the last deglaciation (,18–9 ka), a period of dramatic temperature and hydrologic changes. The results demonstrate that climatic controls on Lake Malawi vegetation are critically important to weathering processes and erosion patterns during the deglaciation. At 18 ka, afromontane forests dominated but were progressively replaced by tropical seasonal forest, as summer rainfall increased. Despite indication of decreased rainfall, drought-intolerant forest persisted through the Younger Dryas (YD) resulting from a shorter dry season. Following the YD, an intensified summer monsoon and increased rainfall seasonality were coeval with forest decline and expansion of drought-tolerant miombo woodland. Clay minerals closely track the vegetation record, with high ratios of kaolinite to smectite (K/S) indicating heavy leaching when forest predominates, despite variable rainfall. In the early Holocene, when rainfall and temperature increased (effective moisture remained low), open woodlands expansion resulted in decreased K/S, suggesting a reduction in chemical weathering intensity. Terrigenous sediment mass accumulation rates also increased, suggesting critical linkages among open vegetation and erosion during intervals of enhanced summer rainfall. This study shows a strong, direct influence of vegetation composition on weathering intensity in the tropics. As climate change will likely impact this interplay between the biosphere and geosphere, tropical landscape change could lead to deleterious effects on soil and water quality in regions with little infrastructure for mitigation. This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication. Data Availability: The authors confirm that all data underlying the findings are fully available without restriction. All relevant data are within the paper and its Supporting Information files. Funding: Lake Malawi Drilling Project-Earth System History Program (NSF-EAR-0602404) funded field operations, logistics, and some laboratory analysis. NSF Graduate Research Fellowship (2009078688) provided student salary and tuition and some travel support for laboratory analysis. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist.
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- 2014
16. Gavialis from the Pleistocene of Thailand and Its Relevance for Drainage Connections from India to Java
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Komsorn Lauprasert, Wilailuck Naksri, Jeremy E. Martin, Eric Buffetaut, Julien Claude, School of Earth Sciences [Bristol], University of Bristol [Bristol], PaleoEnvironnements et PaleobioSphere (PEPS), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de l'Evolution de Montpellier (UMR ISEM), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Institut de recherche pour le développement [IRD] : UR226-Centre National de la Recherche Scientifique (CNRS), and Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École Pratique des Hautes Études (EPHE)
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0106 biological sciences ,010506 paleontology ,Early Pleistocene ,Pleistocene ,Landform History ,Science ,[SDV]Life Sciences [q-bio] ,Vertebrate Paleontology ,Endangered species ,Fluvial ,India ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,[SDV.BID]Life Sciences [q-bio]/Biodiversity ,010603 evolutionary biology ,01 natural sciences ,Genus ,Animals ,Paleoclimatology ,Biology ,Gavialis ,0105 earth and related environmental sciences ,Evolutionary Biology ,Alligators and Crocodiles ,Multidisciplinary ,biology ,Ecology ,Geography ,Fossils ,Geographical Hydrology ,Paleontology ,Biostratigraphy ,Geomorphology ,15. Life on land ,biology.organism_classification ,Thailand ,Biogeography ,Physical Geography ,Indonesia ,Earth Sciences ,Biological dispersal ,Medicine ,Mainland ,Paleoecology ,Paleobiology ,[SDU.STU.PG]Sciences of the Universe [physics]/Earth Sciences/Paleontology ,Research Article - Abstract
BackgroundThe genus Gavialis comprises a single living but endangered species, G. gangeticus, as well as fossil species recorded in the Miocene to Pleistocene deposits of the Indian subcontinent. The genus is also represented in the Pleistocene deposits of Java by the species G. bengawanicus, which was recently recognized to be valid. Surprisingly, no detailed report of the genus exists between these two provinces and the recent evolutionary history of Gavialis is not understood.Methodology/principal findingsWe report new material consisting of skull and mandibular remains of Gavialis from the Early Pleistocene of Khok Sung, Nakhon Ratchasima Province, northeastern Thailand. The Gavialis material described herein is attributed to Gavialis cf. bengawanicus and sheds new light on the occurrence of the genus in mainland SE Asia.Conclusions/significanceComparison of this new material with other species referred to the genus Gavialis led us to preliminary restrict the content of the genus to three species, namely G. gangeticus Gmelin, G. bengawanicus Dubois and G. lewisi Lull. The occurrence of G. cf. bengawanicus in Thailand allows us to propose a scenario for the dispersal of Gavialis from Indo-Pakistan to Indonesia, thus bridging a geographical gap between these two provinces. Dispersal by sea appears a less likely possibility than dispersal through fluvial drainages.
- Published
- 2012
17. Cryptic diversity of African tigerfish (genus Hydrocynus) reveals palaeogeographic signatures of linked neogene geotectonic events
- Author
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Sarah Goodier, Paul H. Skelton, Colleen O'Ryan, Fenton P.D. Cotterill, and Maarten J. de Wit
- Subjects
Time Factors ,Range (biology) ,Landform History ,Population Dynamics ,Marine and Aquatic Sciences ,lcsh:Medicine ,Hydrocynus tanzaniae ,Animal Phylogenetics ,Structural Geology ,Clade ,lcsh:Science ,Phylogeny ,Freshwater Ecology ,Multidisciplinary ,biology ,Geography ,Ecology ,Cenozoic ,Fishes ,Geographical Hydrology ,Paleogenetics ,Geology ,Cytochromes b ,Plate Tectonics ,Biogeography ,Surface Earth Movement ,Ichthyology ,Research Article ,Geological Phenomena ,Molecular Sequence Data ,DNA, Mitochondrial ,Models, Biological ,Rivers ,Species Specificity ,Biosphere ,Phylogenetics ,Vicariance ,Genetics ,Animals ,Biology ,Ecosystem ,Evolutionary Biology ,lcsh:R ,Genetic Variation ,Paleontology ,Bayes Theorem ,Geomorphology ,Geologic Time ,biology.organism_classification ,Landform Dynamics ,Phylogeography ,Lakes ,Haplotypes ,Physical Geography ,Animal Taxonomy ,Africa ,Earth Sciences ,lcsh:Q ,Hydrocynus ,Zoology - Abstract
The geobiotic history of landscapes can exhibit controls by tectonics over biotic evolution. This causal relationship positions ecologically specialized species as biotic indicators to decipher details of landscape evolution. Phylogeographic statistics that reconstruct spatio-temporal details of evolutionary histories of aquatic species, including fishes, can reveal key events of drainage evolution, notably where geochronological resolution is insufficient. Where geochronological resolution is insufficient, phylogeographic statistics that reconstruct spatio-temporal details of evolutionary histories of aquatic species, notably fishes, can reveal key events of drainage evolution. This study evaluates paleo-environmental causes of mitochondrial DNA (mtDNA) based phylogeographic records of tigerfishes, genus Hydrocynus, in order to reconstruct their evolutionary history in relation to landscape evolution across Africa. Strong geographical structuring in a cytochrome b (cyt-b) gene phylogeny confirms the established morphological diversity of Hydrocynus and reveals the existence of five previously unknown lineages, with Hydrocynus tanzaniae sister to a clade comprising three previously unknown lineages (Groups B, C and D) and H. vittatus. The dated phylogeny constrains the principal cladogenic events that have structured Hydrocynus diversity from the late Miocene to the Plio-Pleistocene (ca. 0–16 Ma). Phylogeographic tests reveal that the diversity and distribution of Hydrocynus reflects a complex history of vicariance and dispersals, whereby range expansions in particular species testify to changes to drainage basins. Principal divergence events in Hydrocynus have interfaced closely with evolving drainage systems across tropical Africa. Tigerfish evolution is attributed to dominant control by pulses of geotectonism across the African plate. Phylogenetic relationships and divergence estimates among the ten mtDNA lineages illustrates where and when local tectonic events modified Africa's Neogene drainage. Haplotypes shared amongst extant Hydrocynus populations across northern Africa testify to recent dispersals that were facilitated by late Neogene connections across the Nilo-Sahelian drainage. These events in tigerfish evolution concur broadly with available geological evidence and reveal prominent control by the African Rift System, evident in the formative events archived in phylogeographic records of tigerfish.
- Published
- 2011
18. Soil moisture: A central and unifying theme in physical geography
- Author
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Tracy L. DeLiberty, Delphis F. Levia, Frederick E. Nelson, Rezaul Mahmood, David R. Legates, Steven M. Quiring, and Chris Houser
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Geography, Planning and Development ,climatology ,hydrology ,geomorphology ,Earth system science ,Geography ,Soil functions ,Earth and Planetary Sciences (miscellaneous) ,General Earth and Planetary Sciences ,Physical geography ,soil moisture ,Water content ,biogeography ,Theme (narrative) - Abstract
Soil moisture is a critical component of the earth system and plays an integrative role among the various subfields of physical geography. This paper highlights not just how soil moisture affects atmospheric, geomorphic, hydrologic, and biologic processes but that it lies at the intersection of these areas of scientific inquiry. Soil moisture impacts earth surface processes in such a way that it creates an obvious synergistic relationship among the various subfields of physical geography. The dispersive and cohesive properties of soil moisture also make it an important variable in regional and microclimatic analyses, landscape denudation and change through weathering, runoff generation and partitioning, mass wasting, and sediment transport. Thus, this paper serves as a call to use research in soil moisture as an integrative and unifying theme in physical geography. © The Author(s) 2010.
- Published
- 2011
19. Evolution of the Western Amazon Lowland Relief: impact of Andean foreland dynamics
- Author
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Matti Räsänen, H. Jungnert, L. Romero Pittman, and J.S. Salo
- Subjects
0106 biological sciences ,010504 meteorology & atmospheric sciences ,Amazon rainforest ,Biogeography ,Fluvial ,Geology ,Rainforest ,15. Life on land ,010603 evolutionary biology ,01 natural sciences ,Sedimentary depositional environment ,Aggradation ,Alluvium ,Physical geography ,Foreland basin ,Geomorphology ,0105 earth and related environmental sciences - Abstract
The congruency in the depositional origin and age of the uppermost sedimentary strata forming non-flooded rainforest ground (terra firme) in the western and central Amazon lowlands is a much debated subject. Here we conclude from the study of remote sensing imagery that active Andean foreland dynamics have played a major role in the evolution of the Plio-Pleistocene fluvial landscape in the western Amazon. Foreland dynamics have resulted in a terra firme composed of late Tertiary alluvium and younger alluvial terraces and plains. In Peru, thermoluminescence and 14C dating show local aggradation of this younger alluvium between 180 and 30 ka. The documented high age heterogeneity of the terra firme has implications for considerations of the biogeography of the Amazon forest.
- Published
- 1990
20. A Hierarchical Classification of Benthic Biodiversity and Assessment of Protected Areas in the Southern Ocean
- Author
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Stefanie Kaiser, Joel Turner, Angelika Brandt, Andrew J. Constable, Rob Nicoll, Ben Raymond, Hedley S. Grantham, Alexandra L. Post, Lucinda L. Douglass, and Daniel Beaver
- Subjects
Aquatic Organisms ,Geologic Sediments ,Range (biology) ,Biodiversity ,Marine and Aquatic Sciences ,Social Sciences ,lcsh:Medicine ,Marine Conservation ,Geoinformatics ,Spatial and Landscape Ecology ,Ice Cover ,lcsh:Science ,Conservation Science ,Multidisciplinary ,Ecology ,Geography ,Marine Ecology ,Biogeography ,Community Ecology ,Habitat ,Benthic zone ,Coastal Ecology ,Environmental Monitoring ,Research Article ,Marine conservation ,Conservation of Natural Resources ,Computer and Information Sciences ,Science Policy ,Oceans and Seas ,Antarctic Regions ,Marine Biology ,Ecosystems ,Ecoregion ,Animals ,Ecology and Environmental Sciences ,lcsh:R ,Biology and Life Sciences ,Aquatic Environments ,Geomorphology ,Marine Environments ,Physical Geography ,Geographic Information Systems ,Earth Sciences ,Biological dispersal ,lcsh:Q ,Marine protected area ,Environmental Protection - Abstract
An international effort is underway to establish a representative system of marine protected areas (MPAs) in the Southern Ocean to help provide for the long-term conservation of marine biodiversity in the region. Important to this undertaking is knowledge of the distribution of benthic assemblages. Here, our aim is to identify the areas where benthic marine assemblages are likely to differ from each other in the Southern Ocean including near-shore Antarctica. We achieve this by using a hierarchical spatial classification of ecoregions, bathomes and environmental types. Ecoregions are defined according to available data on biogeographic patterns and environmental drivers on dispersal. Bathomes are identified according to depth strata defined by species distributions. Environmental types are uniquely classified according to the geomorphic features found within the bathomes in each ecoregion. We identified 23 ecoregions and nine bathomes. From a set of 28 types of geomorphic features of the seabed, 562 unique environmental types were classified for the Southern Ocean. We applied the environmental types as surrogates of different assemblages of biodiversity to assess the representativeness of existing MPAs. We found that 12 ecoregions are not represented in MPAs and that no ecoregion has their full range of environmental types represented in MPAs. Current MPA planning processes, if implemented, will substantially increase the representation of environmental types particularly within 8 ecoregions. To meet internationally agreed conservation goals, additional MPAs will be needed. To assist with this process, we identified 107 spatially restricted environmental types, which should be considered for inclusion in future MPAs. Detailed supplementary data including a spatial dataset are provided.
- Published
- 2014
21. Multi-Scale Approach for Predicting Fish Species Distributions across Coral Reef Seascapes
- Author
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Kerry A. Brown and Simon J. Pittman
- Subjects
Ecological Metrics ,Oceans and Seas ,Marine and Aquatic Sciences ,lcsh:Medicine ,Marine Biology ,Spatial distribution ,Models, Biological ,Essential fish habitat ,Species Specificity ,Geoinformatics ,Relative Abundance Distribution ,Animals ,Spatial and Landscape Ecology ,Marine ecosystem ,Macroecology ,lcsh:Science ,Biology ,geography ,Remote Sensing Imagery ,Multidisciplinary ,geography.geographical_feature_category ,Geography ,Ecology ,Coral Reefs ,Puerto Rico ,lcsh:R ,Fishes ,Marine Ecology ,Geomorphology ,Marine spatial planning ,Biodiversity ,Marine Technology ,Coral reef ,Environmental niche modelling ,Caribbean Region ,Biogeography ,Area Under Curve ,Earth Sciences ,Regression Analysis ,lcsh:Q ,Marine protected area ,Physical geography ,Landscape ecology ,Zoology ,Algorithms ,Coastal Ecology ,Ichthyology ,Research Article - Abstract
Two of the major limitations to effective management of coral reef ecosystems are a lack of information on the spatial distribution of marine species and a paucity of data on the interacting environmental variables that drive distributional patterns. Advances in marine remote sensing, together with the novel integration of landscape ecology and advanced niche modelling techniques provide an unprecedented opportunity to reliably model and map marine species distributions across many kilometres of coral reef ecosystems. We developed a multi-scale approach using three-dimensional seafloor morphology and across-shelf location to predict spatial distributions for five common Caribbean fish species. Seascape topography was quantified from high resolution bathymetry at five spatial scales (5–300 m radii) surrounding fish survey sites. Model performance and map accuracy was assessed for two high performing machine-learning algorithms: Boosted Regression Trees (BRT) and Maximum Entropy Species Distribution Modelling (MaxEnt). The three most important predictors were geographical location across the shelf, followed by a measure of topographic complexity. Predictor contribution differed among species, yet rarely changed across spatial scales. BRT provided ‘outstanding’ model predictions (AUC = >0.9) for three of five fish species. MaxEnt provided ‘outstanding’ model predictions for two of five species, with the remaining three models considered ‘excellent’ (AUC = 0.8–0.9). In contrast, MaxEnt spatial predictions were markedly more accurate (92% map accuracy) than BRT (68% map accuracy). We demonstrate that reliable spatial predictions for a range of key fish species can be achieved by modelling the interaction between the geographical location across the shelf and the topographic heterogeneity of seafloor structure. This multi-scale, analytic approach is an important new cost-effective tool to accurately delineate essential fish habitat and support conservation prioritization in marine protected area design, zoning in marine spatial planning, and ecosystem-based fisheries management.
- Published
- 2011
22. Whither Physical Geography?
- Author
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Rhoads, Bruce L.
- Published
- 2004
23. Restructuring Physical Geography
- Author
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Gregory, K. J., Gurnell, A. M., and Petts, G. E.
- Published
- 2002
24. A Century of Physical Geography Research in the "Annals"
- Author
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Aspinall, Richard
- Published
- 2010
25. Why Not in My Back Yard? : Field-Based Physical Geography Research in the Southeast
- Author
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PEASE, PATRICK P. and GENTRY, GLENN W.
- Published
- 2004
26. Geography in the United Kingdom, 1976-80: Report to the 24th International Geographical Congress in Tokyo, Japan, in August 1980
- Author
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Doornkamp, J. C. and Warren, K.
- Published
- 1980
- Full Text
- View/download PDF
27. The Institute, Study Groups, and a Discipline without a Core?
- Author
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Johnston, R. J.
- Published
- 1989
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