Position of the palaeontological site Aven I des Abîmes de La Fage, at Noailles (Corrèze, France), in the European Pleistocene chronology     

CÉCILE MOURER-CHAUVIRÈ  MICHEL PHILIPPE  YVES QUINIF  JEAN CHALINE  EVELYNE DEBARD  CLAUDE GUÉRIN  MARGUERITE HUGUENEY 《Boreas: An International Journal of Quaternary Research》2003,32(3):521-531

Mourer-Chauviré, C., Philippe, M., Quinif, Y., Chaline, J., Debard, E., Guérin, C. & Hugueney, M. 2003 (September): Position of the palaeontological site Aven I des Abîmes de La Fage, at Noailles (Corrèze, France), in the European Pleistocene chronology. Boreas , Vol. 32, pp. 521–531. Oslo. ISSN 0300–9483.
The palaeontological locality of Aven I des Abîmes de La Fage, at Noailles, Corrèze, France, is a limestone swallow hole filling which includes a rich fauna of micro- and macromammals, and one of the most complete Pleistocene avifaunas in the Palearctic. According to the mammal fauna and to the sedimentological study, the filling was previously assigned to the penultimate, Saalian, glaciation. U/Th datings made on a stalagmitic floor deposited in a lateral gallery on top of the filling confirm this previous attribution. Revised lists of the mammal and bird faunas are provided. The comparison of the La Fage fauna with that of other European localities, radiochronologically or biostratigraphically dated, leads to the conclusion that most of the fossiliferous layers were deposited during the Marine Isotope Stage (MIS) 8 (242 to 301 ka).  相似文献   

A first-order analysis of the potential rôle of CO₂ fertilization to affect the global carbon budget: a comparison of four terrestrial biosphere models     

DAVID W. KICKLIGHTER  MICHELE BRUNO  SILKE DÖNGES  GERD ESSER  MARTIN HEIMANN  JOHN HELFRICH  FRANK IFT  FORTUNAT JOOS  JÖRG KADUK  GUNDOLF H. KOHLMAIER  A. DAVID McGUIRE  JERRY M. MELILLO  ROBERT MEYER  BERRIEN MOORE III  REAS NADLER  I. COLIN PRENTICE  WALTER SAUF  ANNETTE L. SCHLOSS  STEPHEN SITCH  UWE WITTENBERG  GUDRUN WÜRTH 《Tellus. Series B, Chemical and physical meteorology》1999,51(2):343-366

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Lateglacial to Holocene relative sea‐level changes in the Stykkishólmur area,northern Snæfellsnes,Iceland          下载免费PDF全文

MARTIN D. BRADER  JEREMY M. LLOYD  MICHAEL J. BENTLEY  ANTHONY J. NEWTON 《第四纪科学杂志》2015,30(5):497-507

Comparatively little research has been undertaken on relative sea‐level (RSL) change in western Iceland. This paper presents the results of diatom, tephrochronological and radiocarbon analyses on six isolation basins and two coastal lowland sediment cores from the Stykkishólmur area, northern Snæfellsnes, western Iceland. The analyses provide a reconstruction of Lateglacial to mid‐Holocene RSL changes in the region. The marine limit is measured to 65–69 m above sea level (asl), with formation being estimated at 13.5 cal ka BP. RSL fall initially occurred rapidly following marine limit formation, until ca. 12.6 cal ka BP, when the rate of RSL fall decreased. RSL fell below present in the Stykkishólmur area during the early Holocene (by ca. 10 cal ka BP). The rates of RSL change noted in the Stykkishólmur area demonstrate lesser ice thicknesses in Snæfellsnes than Vestfirðir during the Younger Dryas, when viewed in the regional context. Consequently, the data provide an insight into patterns of glacio‐isostatic adjustment surrounding Breiðafjörður, a hypothesized major ice stream at the Last Glacial Maximum.  相似文献   

Long‐term summer (AD751–2008) temperature fluctuation in the French Alps based on tree‐ring data     

CHRISTOPHE CORONA  JEAN‐LOUIS EDOUARD  FREDERIC GUIBAL  JOEL GUIOT  SYLVAIN BERNARD  ANDRE THOMAS  NICOLE DENELLE 《Boreas: An International Journal of Quaternary Research》2011,40(2):351-366

Corona, C., Edouard, J.‐L., Guibal, F., Guiot, J., Bernard, S., Thomas, A. & Denelle, N. 2010: Long‐term summer (AD751–2008) temperature fluctuation in the French Alps based on tree‐ring data. Boreas, 10.1111/j.1502‐3885.2010.00185.x. ISSN 0300‐9843. On the basis of a dense tree‐ring width network (34 unpublished multi‐centennial larch chronologies), this paper attempts to reconstruct, for the first time, the summer temperatures in the French Alps (44°–45.30°N, 6.30°–7.45°E) during the last millennium. The adaptative Regional Growth Curve standardization method is applied to preserve interannual to multi‐centennial variations in this high‐elevation proxy data set. The proxies are calibrated using the June to August mean temperatures from the last revised version of the HISTALP database spanning the period AD1760–2003 and adjusted to take into account the warm bias before 1850. About 45% of the temperature variance is reconstructed. Despite the use of the newly updated meteorological data set, the reconstruction still shows colder temperatures than early instrumental measurements between 1760 and 1840. The proxy record evidences a prolonged Medieval Warm Period persisting until 1500, with warm periods that resemble 20th century conditions but also cold phases before 1000 synchronous with Swiss glacier advances. The Little Ice Age is rather mild until 1660 if compared with other Alpine reconstructions. Thereafter, summers are 0.7 °C cooler than the 1961–1990 mean until 1920. The maximum temperature amplitude over the past 1250 years is estimated to be 3 °C between the warmest (810s, 1990s) and coldest (1810s) decades. Most of the 20th century is comparable with the Medieval Warm Period.  相似文献   

Bank erosion in an Andean páramo river system: Implications for hydro-development and carbon dynamics in the neotropical Andes     

Derek J.MARTIN  Christopher ELY  Beverley C.WEMPLE 《山地科学学报》2019,(2)

The páramo of the Northern Andes provide critically important ecosystem services to the Northern Andean region in the form of water provisioning and carbon sequestration, both of which are a result of the páramo?s organic-rich soils. Little is known, however, about the hydro-geomorphic characteristics of the rivers that drain these ecosystems. With impending plans for widespread hydro-development and increasing implementation of carbon-sequestering compensation for ecosystem services programs in the region it is imperative that we develop a thorough understanding of the hydrogeomorphic role that rivers play in this unique ecosystem. The objective of this study was to quantify bank erosion along an Amazonian headwater stream draining a small, relatively undisturbed páramo catchment to gain a better understanding of the natural erosion regime and the resulting sediment contributions from this unique ecosystem. This study implemented a combination of field, laboratory, and Geographic Information Systems techniques to quantify bank erosion rates and determine a bank erosion sediment yield from the Ningar River, a small páramo catchment(22.7 km~2) located in the eastern Andean cordillera of Ecuador. Results show that bank erosion rates range from 3.0 to ≥ 390.0 mm/yr, are highly episodic, and yield at least 487 tons of sediment annually to the Ningar River. These results imply that 1) páramo ecosystems substantially contribute to the sediment load of the Amazon River basin; 2) bank erosion is a potentially significant flux component of basin-scale carbon cycles in páramo ecosystems; and 3) hydrologic alteration campaigns(dam building) will likely critically alter these contributions and concomitantly disconnect a critical source of sediment and nutrients to downstream ecosystems.  相似文献   

Holocene deglaciation and recent ice-marginal processes in west Greenland,F. G. M. VAN TATENHOVE,PhD Thesis,Universiteit van Amsterdam 1995; (202 pp) ISBN 90-6787-039-0     

MARTIN KIRKBRIDE 《第四纪科学杂志》1997,12(1):81-82

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AN INTEGRATED APPROACH TO MODELLING HYDROLOGY AND WATER QUALITY IN GLACIERIZED CATCHMENTS     

KEITH RICHARDS  MARTIN SHARP  NEIL ARNOLD  ANGELA GURNELL  MICHAEL CLARK  MARTIN TRANTER  PETER NIENOW  GILES BROWN  IAN WILLIS  WENDY LAWSON 《水文研究》1996,10(4):479-508

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Mountain-wave-induced record low stratospheric temperatures above northern Scandinavia   总被引：1，自引：0，他引：1  

ANDREAS DÖRNBRACK  MARTIN LEUTBECHER  RIGEL KIVI  ESKO. KYRÖ 《地球，A辑:动力气象学与海洋学》1999,51(5):951-963

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A MARITIME RESPONSE TO THE CRISIS IN AREA STUDIES     

MARTIN W. LEWIS  KREN WIGEN 《Geographical review》1999,89(2):161-168

ABSTRACT. The area-studies model of global scholarship, based on dividing the world into a set number of large, quasi-continental regions, is under assault from a variety of intellectual and institutional forces. New, less rigid models of global scholarship are increasingly being called for by both scholars and funding agencies. One useful alternative, currently being explored at Duke University, reframes area studies around ocean and sea basins. Putting maritime interactions at the center of vision brings to light a set of historical regions that have largely remained invisible on the conventional map of the world.  相似文献   

Solar irradiance during the last 1200 years based on cosmogenic nuclides   总被引：12，自引：0，他引：12  

EDOUARD BARD  GRANT RAISBECK  FRANÇOISE YIOU  JEAN JOUZEL 《Tellus. Series B, Chemical and physical meteorology》2000,52(3):985-992

Based on a quantitative study of the common fluctuations of ¹⁴C and ¹⁰Be production rates, we have derived a time series of the solar magnetic variability over the last 1200 years. This record is converted into irradiance variations by linear scaling based on previous studies of sun‐like stars and of the sun's behavior over the last few centuries. The new solar irradiance record exhibits low values during the well‐known solar minima centered at about 1900, 1810 (Dalton) and 1690 ad (Maunder). Further back in time, a rather long period between 1450 and 1750 ad is characterized by low irradiance values. A shorter period is centered at about 1200 ad , with irradiance slightly higher or similar to present day values. It is tempting to correlate these periods with the so‐called "little ice age" and "medieval warm period", respectively. An accurate quantification of the climatic impact of this new irradiance record requires the use of coupled atmosphere–ocean general circulation models (GCMs). Nevertheless, our record is already compatible with a global cooling of about 0.5‐1°C during the "little ice age", and with a general cooling trend during the past millenium followed by global warming during the 20th century (Mann et al., 1999).  相似文献