Ceilometer observations of aerosol layer structure above the Petit Lubéron during ESCOMPTE's IOP 2     

Marcel Zphoris  Hubert Holin  Franck Lavie  Nadine Cenac  Michel Cluzeau  Olivier Delas  Franoise Eideliman  Jacqueline Gagneux  Alain Gander  Corinne Thibord 《Atmospheric Research》2005,74(1-4):581-595

A modified ceilometer has been used during the second Intensive Observation Period (IOP) of the “Expérience sur Site pour COntraindre les Modèles de Pollution atmosphériques et de Transport d'Émission” (ESCOMPTE) to perform continuous remote observations of aerosol accumulations in the first 3 km of the atmosphere. These observations encompassed an episode of intense particulate and photochemical pollution. The submicronic particles density, measured at an altitude of 600 m, went from a very low point of a few tens of particles per cubic centimeter (at the end of a Mistral episode in the free atmosphere) to a high point of more than 4500 particles per cubic centimeter (when pollutants were trapped by thermal inversions).The main result is that this instrument enables a fine documentation of the mixing layer height and of aerosol particles stratifications and circulation. Airborne aerosol measurements have been made above the mountainous region of Mérindol in order to validate in situ the remote sensing measurements. Ozone measurements near the summit of the mountains as well as in the valley were performed in order to correlate aerosol accumulation and ozone concentration. As a notable example, the two-layer aerosol stratification seen in the first 2 days of IOP 2b in that part of the ESCOMPTE domain confirms the results of another team which used backtrajectories. The low-altitude pollution for this timeframe had a local origin (the Fos industrial area), whereas above 500 m, the air masses had undergone regional-scale transport (from north-eastern Spain).The second major result is the highlighting of a pattern, in sea breeze conditions and in this part of the ESCOMPTE experiment zone, of nocturnal aerosol accumulation at an altitude of between 500 and 2000 m, followed by high ozone concentration the next day.  相似文献   

Lithospheric evolution of the Andean fold–thrust belt, Bolivia, and the origin of the central Andean plateau   总被引：1，自引：1，他引：1  

Nadine McQuarrie  Brian K. Horton  George Zandt  Susan Beck  Peter G. DeCelles 《Tectonophysics》2005,399(1-4):15

We combine geological and geophysical data to develop a generalized model for the lithospheric evolution of the central Andean plateau between 18° and 20° S from Late Cretaceous to present. By integrating geophysical results of upper mantle structure, crustal thickness, and composition with recently published structural, stratigraphic, and thermochronologic data, we emphasize the importance of both the crust and upper mantle in the evolution of the central Andean plateau. Four key steps in the evolution of the Andean plateau are as follows. 1) Initiation of mountain building by 70 Ma suggested by the associated foreland basin depositional history. 2) Eastward jump of a narrow, early fold–thrust belt at 40 Ma through the eastward propagation of a 200–400-km-long basement thrust sheet. 3) Continued shortening within the Eastern Cordillera from 40 to 15 Ma, which thickened the crust and mantle and established the eastern boundary of the modern central Andean plateau. Removal of excess mantle through lithospheric delamination at the Eastern Cordillera–Altiplano boundary during the early Miocene appears necessary to accommodate underthrusting of the Brazilian shield. Replacement of mantle lithosphere by hot asthenosphere may have provided the heat source for a pulse of mafic volcanism in the Eastern Cordillera and Altiplano at 24–23 Ma, and further volcanism recorded by 12–7 Ma crustal ignimbrites. 4) After 20 Ma, deformation waned in the Eastern Cordillera and Interandean zone and began to be transferred into the Subandean zone. Long-term rates of shortening in the fold–thrust belt indicate that the average shortening rate has remained fairly constant (8–10 mm/year) through time with possible slowing (5–7 mm/year) in the last 15–20 myr. We suggest that Cenozoic deformation within the mantle lithosphere has been focused at the Eastern Cordillera–Altiplano boundary where the mantle most likely continues to be removed through piecemeal delamination.  相似文献   

The Val Gabbro Plutonic Suite: A Sub-volcanic Intrusion Emplaced at the End of Flood Basalt Volcanism on the Kerguelen Archipelago     

Scoates  James S.; Weis  Dominique; Franssens  Matthias; Mattielli  Nadine; Annell  Heidi; Frey  Frederick A.; Nicolaysen  Kirsten; Giret  Andre 《Journal of Petrology》2008,49(1):79-105

The age, petrology, major and trace element geochemistry, andSr–Nd–Hf–Pb isotopic geochemistry of basicand felsic rocks from the Val gabbro plutonic suite on the KerguelenArchipelago, Southern Indian Ocean, are used to constrain thetemporal and compositional relationships between sub-volcanicintrusions and flood basalt volcanism during the formation ofa major oceanic island. The 4 km² Val gabbro plutonic suitewas emplaced at 24·25 ± 0·15 Ma (U–Pbzircon) into 25 Ma volcanic rocks of the Southeast Province,locally producing a large zone of overlying basaltic breccia.Cumulate basic–ultrabasic rocks are the dominant lithologyin the intrusion, with horizontally layered peridotites at thebase of the exposed part of the intrusion, overlain by verticallylayered, coarse-grained plagioclase-bearing peridotites, melagabbrosand equigranular gabbros. The intrusion was formed by repeatedinjections of relatively crystal-rich and crystal-poor magmasinto an open-system magma reservoir. Strong geochemical andisotopic similarities between the fine-grained marginal microgabbrosand cross-cutting felsic rocks and the hosting mildly alkalicbasalts and trachytes of the Southeast Province indicate thatthey were derived from similar alkalic basaltic parental magmas,which were dominated by the enriched component of the Kerguelenmantle plume source. At 25 Ma, the change from tholeiitic–transitionalto mildly alkalic basalts marks the terminal stage of floodbasalt volcanism on the Kerguelen Archipelago. This compositionalchange was associated with deeper melting within the Kerguelenplume source, lower extents of melting, a decrease in magmasupply, and the emplacement of high-level intrusions such asthe Val gabbro plutonic suite. KEY WORDS: Kerguelen Archipelago; Val gabbro plutonic suite; oceanic island; gabbros; sub-volcanic intrusion; alkalinity; Sr–Nd–Hf–Pb isotopes  相似文献   

Environmental geochemistry of a Kuroko-type massive sulfide deposit at the abandoned Valzinco mine,Virginia, USA     

Robert R. Seal II  Jane M. HammarstromAdam N. Johnson  Nadine M. PiatakGregory A. Wandless 《Applied Geochemistry》2008

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Drivers of Change and Sustainability in Linked Social–Ecological Systems: An Analysis in the Volta River Basin of Ghana,West Africa     

Julius H. Kotir  Greg Brown  Nadine Marshall  Ron Johnstone 《社会与自然资源》2017,30(10):1229-1245

Understanding the nature and relative importance of various drivers of change is crucial for sustainable management of natural resources and in prioritizing management efforts, allocating limited resources, and understanding cumulative effects. For this article, we employed structured an expert judgments approach to identify, characterize, and assess the relative importance of the key biophysical and socioeconomic drivers of change within the Volta River Basin, West Africa. Precipitation variability, water availability, land use change, drought events, and population growth were perceived as most important, while biodiversity loss, social conflicts, pest and disease occurrence, urbanization, and pollution were viewed as less critical. A majority of these drivers were characterized as “slow” acting processes as compared to rapidly changing drivers. Intra- and interexpert groups agreement were found to be significant and convergent, indicating the reliability of the results. The implications of these results for sustainable water resources management and agricultural production are discussed.  相似文献   

Cluster Analysis of Atmospheric Dynamics and Pollution Transport in a Coastal Area     

Anton Sokolov  Egor Dmitriev  Elena Maksimovich  Hervé Delbarre  Patrick Augustin  Cyril Gengembre  Marc Fourmentin  Nadine Locoge 《Boundary-Layer Meteorology》2016,161(2):237-264

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Assessment of putative endocrine disrupters in an in vivo crustacean assay and an in vitro insect assay     

Pounds NA  Hutchinson TH  Williams TD  Whiting P  Dinan L 《Marine environmental research》2002,54(3-5):709-713

Concern over endocrine disrupters in coastal ecosystems has stimulated global efforts to understand their potential impacts on fish and invertebrate communities. Given that marine crustaceans are sensitive to the effects of alkylphenols and other xenobiotics, we are currently investigating whether these responses may be caused via an endocrine mechanism. Tisbe battagliai (Copepoda: Harpacticoida) is representative of an ecologically important group of meiofauna, is sensitive to toxicants and is used as an international test species in marine ecotoxicology. A 21-day life-cycle test that incorporates assessment of survival, development, reproduction and sex ratios, has shown that populations of T. battagliai are not significantly affected by environmentally relevant levels of steroidal oestrogen agonists, or by related synthetic receptor agonists. The absence of in vivo effects due to these steroid agonists and antagonists prompted in vitro studies of ecdysteroid receptor activity of a range of reference compounds and environmental contaminants with an ecdysteroid receptor (EcR/USP)-based screening assay derived from the BII haemocyte line of Drosophila melanogaster. The implications for environmental monitoring of endocrine disrupters are discussed.  相似文献   

Petrographic investigations in cemeteries in Dresden: a scientific view on the tombstone inventory including historic and cultural aspects     

Jan-Michael Lange  Martin Kaden  Nadine Janetschke 《Environmental Earth Sciences》2018,77(17):620

Cemeteries give evidence for a continuous change in sepulchral culture and provide insights into the application of characteristical rock materials used for tombstones during different times. Four selected cemeteries in Dresden (the Eliasfriedhof/Elias Cemetery, the Trinitatisfriedhof/Trinity Cemetery, the Johannisfriedhof/Johannis Cemetery, and the Städtischer Urnenhain/Municipal Urn Grove), which are of considerable cultural and historical importance, have been investigated within an ongoing mapping project. First results of this project focussing on the tombstone inventory of the mentioned graveyards and thus the use of building and decoration stones therein between 1680 and 1945 are presented in this paper. It can be demonstrated that the choice, variety, and application of rock material depends on the infrastructure and transport possibilities, but is also strongly influenced by sepulchral cultural trends and the prevailing zeitgeist. Until the middle of the 19th century, nearly solely Elbe sandstone (from the area of the Elbsandsteingebirge/Elbe sandstone mountains), that was transported on the Elbe river by ship, is found as rock material for tombstones in Dresden cemeteries. Rapid construction and development of the railway network starting around 1840 improved the availability, at first, of regional rock material (e.g., from the Lausitz/Lusatia) and, later on, from about 1880, of national and international—especially European—rock material (e.g., from Franken/Franconia, France, Scandinavia). Furthermore, the Friedhofsreformbewegung/cemetery reform movement at the beginning of the 20th century, with its significant effect on the selection of rock types used for tombstones, marks another historical breakthrough.  相似文献   

Hydrogeological controls of variable microbial water quality in a complex subtropical karst system in Northern Vietnam     

Anna Ender  Nadine Goeppert  Nico Goldscheider 《Hydrogeology Journal》2018,26(7):2297-2314

Karst aquifers are particularly vulnerable to bacterial contamination. Especially in developing countries, poor microbial water quality poses a threat to human health. In order to develop effective groundwater protection strategies, a profound understanding of the hydrogeological setting is crucial. The goal of this study was to elucidate the relationships between high spatio-temporal variability in microbial contamination and the hydrogeological conditions. Based on extensive field studies, including mapping, tracer tests and hydrochemical analyses, a conceptual hydrogeological model was developed for a remote and geologically complex karst area in Northern Vietnam called Dong Van. Four different physicochemical water types were identified; the most important ones correspond to the karstified Bac Son and the fractured Na Quan aquifer. Alongside comprehensive investigation of the local hydrogeology, water quality was evaluated by analysis for three types of fecal indicator bacteria (FIB): Escherichia coli, enterococci and thermotolerant coliforms. The major findings are: (1) Springs from the Bac Son formation displayed the highest microbial contamination, while (2) springs that are involved in a polje series with connections to sinking streams were distinctly more contaminated than springs with a catchment area characterized by a more diffuse infiltration. (3) FIB concentrations are dependent on the season, with higher values under wet season conditions. Furthermore, (4) the type of spring capture also affects the water quality. Nevertheless, all studied springs were faecally impacted, along with several shallow wells within the confined karst aquifer. Based on these findings, effective protection strategies can be developed to improve groundwater quality.  相似文献   

Erratum: Impact of managed aquifer recharge on the chemical and isotopic composition of a karst aquifer,Wala reservoir,Jordan     

Julian Xanke  Nadine Goeppert  Ali Sawarieh  Tanja Liesch  Jochen Klinger  Wasim Ali  Heinz Hötzl  Khair Hadidi  Nico Goldscheider 《Hydrogeology Journal》2015,23(5):1041-1041

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