Non-linear Langevin model of geomorphic erosion processes   总被引：1，自引：0，他引：1  

Didier Sornette  Yi-Cheng Zhang 《Geophysical Journal International》1993,113(2):382-386

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Magnetostratigraphy of the Hettangian Langmoos section (Adnet, Austria): evidence for time-delayed phases of magnetization     

Yves Gallet  Didier Vandamme  Leopold Krystyn 《Geophysical Journal International》1993,115(2):575-585

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Long-term evolution of fish communities in European mountainous rivers: past log driving effects,river management and species introduction (Salzach River,Danube)     

Gertrud Haidvogl  Didier Pont  Horst Dolak  Severin Hohensinner 《Aquatic Sciences - Research Across Boundaries》2015,77(3):395-410

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Historical ecology of riverine fish in Europe     

Gertrud Haidvogl  Richard Hoffmann  Didier Pont  Mathias Jungwirth  Verena Winiwarter 《Aquatic Sciences - Research Across Boundaries》2015,77(3):315-324

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Impact of terrestrial runoff on organic matter,trophic state,and phytoplankton in a tropical,upland reservoir     

Duc Anh Trinh  Thi Nguyet Minh Luu  Quan Hong Trinh  Hai Sy Tran  Tien Minh Tran  Thi Phuong Quynh Le  Thuy Thi Duong  Didier Orange  Jean Louis Janeau  Thomas Pommier  Emma Rochelle-Newall 《Aquatic Sciences - Research Across Boundaries》2016,78(2):367-379

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Holocene phreatomagmatic eruptions alongside the densely populated northern shoreline of Lake Kivu,East African Rift: timing and hazard implications     

Sam Poppe  Benoît Smets  Karen Fontijn  Montfort Bagalwa Rukeza  Antoine De Marie Fikiri Migabo  Albert Kyambikwa Milungu  Didier Birimwiragi Namogo  François Kervyn  Matthieu Kervyn 《Bulletin of Volcanology》2016,78(11):82

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Simulating bubble number density of rhyolitic pumices from Plinian eruptions: constraints from fast decompression experiments     

Morihisa Hamada  Didier Laporte  Nicolas Cluzel  Kenneth T. Koga  Tatsuhiko Kawamoto 《Bulletin of Volcanology》2010,72(6):735-746

Decompression experiments of a crystal-free rhyolitic liquid with ≈ 6.6 wt. % H₂O were carried out at a pressure range from 250 MPa to 30–75 MPa in order to characterize effects of magma ascent rate and temperature on bubble nucleation kinetics, especially on the bubble number density (BND, the number of bubbles produced per unit volume of liquid). A first series of experiments at 800°C and fast decompression rates (10–90 MPa/s) produced huge BNDs (≈ 2 × 10¹⁴ m⁻³ at 10 MPa/s ; ≈ 2 × 10¹⁵ m⁻³ at 90 MPa/s), comparable to those in natural silicic pumices from Plinian eruptions (10¹⁵–10¹⁶ m⁻³). A second series of experiments at 700°C and 1 MPa/s produced BNDs (≈ 9×10¹² m⁻³) close to those observed at 800°C and 1 MPa/s (≈ 6 × 10¹² m⁻³), showing that temperature has an insignificant effect on BNDs at a given decompression rate. Our study strengthens the theory that the BNDs are good markers of the decompression rate of magmas in volcanic conduits, irrespective of temperature. Huge number densities of small bubbles in natural silicic pumices from Plinian eruptions imply that a major nucleation event occurs just below the fragmentation level, at which the decompression rate of ascending magmas is a maximum (≥ 1 MPa/s).  相似文献   

Drivers of afforestation in Northern Vietnam: Assessing local variations using geographically weighted regression   总被引：2，自引：0，他引：2  

Floriane Clement  Didier Orange  Meredith Williams  Corinne Mulley  Michael Epprecht 《Applied geography (Sevenoaks, England)》2009,29(4):561-576

This article identifies drivers of forest transition in a province of Northern Vietnam between 1993 and 2000 by applying geographically weighted regression (GWR) analysis to remotely sensed and statistical data. The regression model highlighted the spatial variation of the relationship between the percentage of land afforested and its proximate causes. Factors identified as having a major impact on afforestation are: the presence or proximity of a wood-processing industry, the distance to highways, and land allocation to households. Whereas the two former variables are in most areas of the province positively correlated with afforestation, an unexpected negative correlation was observed for the latter. The analysis of these results, supported by an in-depth knowledge of the area and of the political context, leads to the conclusion that, during the time period considered, afforestation was largely driven by state organisations on protected state-owned land, and forestry was not a significant component of household economic activities.  相似文献   

Sheathed prokaryotic filaments,major components of Mid-Cretaceous French amber microcoenoses     

Vincent Girard  Gérard Breton  Luc Brient  Didier Néraudeau 《Journal of Paleolimnology》2009,42(3):437-447

Prokaryotes were the first organisms to colonize Earth, but little evidence of their existence has been found in the fossil record. Recent studies of amber, a fossil resin from gymnosperms or angiosperms, have revealed a number of rarely fossilized microorganisms. Several amber-bearing localities of Mid-Cretaceous age in southwestern France (Charentes and Aude regions) led to the discovery of a rich and diverse biota of resin-preserved microorganisms. These amber microcoenoses are dominated by sheathed prokaryotic filaments similar to those of the cyanobacterium Palaeocolteronema cenomanensis Breton and Tostain (2005) and to those of the bacterium Leptotrichites resinatus Schmidt 2005. These sheathed filaments appear as peripheral cortexes around some pieces of amber from the Charentes outcrops and as peripheral dark areas on amber from the Aude locality. Macroscopic and microscopic features, as well as measurements of phycocyanin concentrations from the filaments, made it possible to identify two different taxa. The sheathed filaments from Charentes correspond to P. cenomanensis. They were growing in freshwater ponds when amber trapped them. Those of the Aude outcrop represent L. resinatus. The latter were probably trapped in less humid environments than were P. cenomanensis filaments.  相似文献   

Identification of stoichiometric iron-phosphorus colloids produced in a eutrophic lake     

Charles-Philippe Lienemann  Marc Monnerat  Janusz Dominik  Didier Perret 《Aquatic Sciences - Research Across Boundaries》1999,61(2):133-149

: Iron-rich colloids formed at the oxic-anoxic interface of a eutrophic lake (Lake Lugano; CH) were characterized by bulk chemical methods and analytical electron microscopy. Fractionation of raw waters showed that non-dissolved iron is particulate above the oxicline and mainly colloidal in the anoxic part of the hypolimnion, while non-dissolved ortho-phosphate is mostly colloidal through the water column. Because of these differences, filtration did not prove helpful for the determination of the role of iron-rich species in the scavenging of ortho-phosphate. On the other hand, analytical electron microscopy revealed that iron-rich nano-granules (ca. 50nm) are associated to the surface of bacterially produced fibrillar polysaccharides. Iron colloids in these complex entities contain important and constant amounts of phosphorus ([PO4]part:[Fe]part = 0.48 - 0.11, n = 1096 Fe-rich entities analyzed by electron microscopy), which suggests that phosphates are stoichiometrically incorporated into the hydrous iron oxide phase, with a tentative composition Fe2[OOH]1-x[(OH)3]x[PO4], during its genesis.  相似文献