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Luc Denys 《Journal of Paleolimnology》2006,35(4):763-787
Relationships between littoral surface-sediment diatom assemblages and ambient limnological conditions were examined in 186
lentic fresh waters throughout lower Belgium (Flanders). Most of these waters were small, unstratified, alkaline and rich
in nutrients. Using weighted-averaging techniques, robust and accurate transfer functions were developed for median pH-values
ranging from 3.4 to 9.3 and dissolved inorganic carbon concentrations from <1.6 to 63 mg l−1 (jackknifed r
2≈ 0.87, RMSEP <10% of the observed range), while a less precise model was obtained for sodium (2–571 mg l−1; jackknifed r
2 0.69, RMSEP 9.9% of the range). Restricting the data set to circumneutral and alkaline sites (pH≥6.5) revealed the importance
of additional variables, including calcium, silica, chemical oxygen demand and potential gross oxygen production (a proxy
for metabolic activity and phytoplankton abundance). Calibration models for these variables were strong enough to be useful
(jackknifed r
2 0.57–0.59, RMSEP 13.1–16.4% of the observed range), although estimations should not always be considered entirely independent.
Except for the predominant pH gradient, removal of all taxa with a distribution unrelated to the variable of interest improved
model performance. In general, such taxa were proportionally represented among taxa classified according to their principal
habitat. Application of the present models to diatom assemblages of shallow-water sediments obtained from historical samples
and, most importantly, herbarium-macrophyte specimens, will improve hindsight into regional freshwater conditions and add
to base-line setting of ecological quality standards in a highly impacted region.
Electronic supplementary material Electronic supplementary material is available for this article at
and accessible for authorised users. 相似文献
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V. E. Pavlov A. M. Pasenko A. V. Shatsillo V. I. Powerman V. V. Shcherbakova S. V. Malyshev 《Izvestiya Physics of the Solid Earth》2018,54(5):782-805
Representative paleomagnetic collections of Lower Cambrian rocks from the northern and eastern regions of the Siberian platform are studied. New evidence demonstrating the anomalous character of the paleomagnetic record in these rocks is obtained. These data confidently support the hypothesis (Pavlov et al., 2004) that in the substantial part of the Lower Cambrian section of the Siberian platform there are two stable high-temperature magnetization components having significantly different directions, each of which is eligible for being a primary component that was formed, at the latest, in the Early Cambrian. The analysis of the world’s paleomagnetic data for this interval of the geological history shows that the peculiarities observed in Siberia in the paleomagnetic record for the Precambrian–Phanerozoic boundary are global, inconsistent with the traditional notion of a paleomagnetic record as reflecting the predominant axial dipole component of the geomagnetic field, and necessitates the assumption that the geomagnetic field at the Proterozoic–Phanerozoic boundary (Ediacaran–Lower Cambrian) substantially differed from the field of most of the other geological epochs. In order to explain the observed paleomagnetic record, we propose a hypothesis suggesting that the geomagnetic field at the Precambrian–Cambrian boundary had an anomalous character. This field was characterized by the presence of two alternating quasi-stable generation regimes. According to our hypothesis, the magnetic field at the Precambrian–Cambrian boundary can be described by the alternation of long periods dominated by an axial, mainly monopolar dipole field and relatively short epochs, lasting a few hundred kA, with the prevalence of the near-equatorial or midlatitude dipole. The proposed hypothesis agrees with the data obtained from studies of the transitional fields of Paleozoic reversals (Khramov and Iosifidi, 2012) and with the results of geodynamo numerical simulations (Aubert and Wicht, 2004; Glatzmayer and Olson, 2005; Gissinger et al., 2012). 相似文献
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Kostyleva V. V. Moiseev A. V. Shchepetova E. V. Basilyan A. E. Golionko B. G. Nikolsky P. A. Khissamutdinova A. I. Malyshev N. A. Verzhbitskiy V. E. Obmetko V. V. Borodulin A. A. 《Lithology and Mineral Resources》2022,57(3):218-233
Lithology and Mineral Resources - The U–Pb (LA-ICP-MS) dating of detrital zircons from the Upper Cretaceous Derevyannye Gory Formation in the Novaya Sibir Island revealed that tuffites and... 相似文献
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Robert Barouki Manolis Kogevinas Karine Audouze Kristine Belesova Ake Bergman Linda Birnbaum Sandra Boekhold Sebastien Denys Celine Desseille Elina Drakvik Howard Frumkin Jeanne Garric Delphine Destoumieux-Garzon Andrew Haines Anke Huss Genon Jensen Spyros Karakitsios Jana Klanova Iida-Maria Koskela Francine Laden Paolo Vineis 《Chemie der Erde / Geochemistry》2011
The outbreak of COVID-19 raised numerous questions on the interactions between the occurrence of new infections, the environment, climate and health. The European Union requested the H2020 HERA project which aims at setting priorities in research on environment, climate and health, to identify relevant research needs regarding Covid-19. The emergence and spread of SARS-CoV-2 appears to be related to urbanization, habitat destruction, live animal trade, intensive livestock farming and global travel. The contribution of climate and air pollution requires additional studies. Importantly, the severity of COVID-19 depends on the interactions between the viral infection, ageing and chronic diseases such as metabolic, respiratory and cardiovascular diseases and obesity which are themselves influenced by environmental stressors. The mechanisms of these interactions deserve additional scrutiny. Both the pandemic and the social response to the disease have elicited an array of behavioural and societal changes that may remain long after the pandemic and that may have long term health effects including on mental health. Recovery plans are currently being discussed or implemented and the environmental and health impacts of those plans are not clearly foreseen. Clearly, COVID-19 will have a long-lasting impact on the environmental health field and will open new research perspectives and policy needs. 相似文献
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A. P. Sorokin V. B. Kaplun Yu. F. Malyshev A. T. Sorokina 《Doklady Earth Sciences》2011,439(2):1084-1087
The Zeya-Bureya Basin is a part of the East Asian intracontinental riftogenic belt, which includes oil-and-gas bearing and
Mesozoic-Cenozoic sedimentary basins perspective for oil and gas (Upper Zeya, Songliao, Liaohe, North Chinese). The basins
are characterized by certain geophysical features: reduced thickness of the Earth’s crust and lithosphere, a higher thermal
flow and a raised roof of the asthenosphere. The Zeya-Bureya Basin is composed of Mesozoic-Cenozoic sedimentary-volcanic units,
with respect to which the deep structure data are absent. In 2010, geoelectric studies were carried out in this territory
using the method of magnetotelluric sounding along the profile Blagoveshchensk-Birokan. These works yielded geoelectric sections
down to 2 and 200 km depth. The sedimentary cover is characterized by electric resistivity of 20–50 Ohm m and by thickness
of 1700 m. In the section, the Khingan-Olonoi volcanogenic trough is distinct for resistivity of 200–300 Ohm m at a background
of 500–1000 Ohm m of the basement rocks. The Zeya-Bureya Basin, in terms of its geophysical characteristics, differs from
oil-and-gas bearing basins of the riftogenic belt (thickness of the lithosphere is increased up to 120 km, thermal flow is
low, 40–47 mW/m2). The structure of mantle underplating is explicitly seen in the section. The geophysical characteristics close to those
of the Zeya-Bureya Depression are typical for gold-bearing structures of the Lower Amur ore district. Nevertheless, manifestations
of oil-and-gas bearing potential in particular grabens are possible. 相似文献
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Robert Barouki Manolis Kogevinas Karine Audouze Kristine Belesova Ake Bergman Linda Birnbaum Sandra Boekhold Sebastien Denys Celine Desseille Elina Drakvik Howard Frumkin Jeanne Garric Delphine Destoumieux-Garzon Andrew Haines Anke Huss Genon Jensen Spyros Karakitsios Jana Klanova Paolo Vineis 《Chemie der Erde / Geochemistry》2013
The outbreak of COVID-19 raised numerous questions on the interactions between the occurrence of new infections, the environment, climate and health. The European Union requested the H2020 HERA project which aims at setting priorities in research on environment, climate and health, to identify relevant research needs regarding Covid-19. The emergence and spread of SARS-CoV-2 appears to be related to urbanization, habitat destruction, live animal trade, intensive livestock farming and global travel. The contribution of climate and air pollution requires additional studies. Importantly, the severity of COVID-19 depends on the interactions between the viral infection, ageing and chronic diseases such as metabolic, respiratory and cardiovascular diseases and obesity which are themselves influenced by environmental stressors. The mechanisms of these interactions deserve additional scrutiny. Both the pandemic and the social response to the disease have elicited an array of behavioural and societal changes that may remain long after the pandemic and that may have long term health effects including on mental health. Recovery plans are currently being discussed or implemented and the environmental and health impacts of those plans are not clearly foreseen. Clearly, COVID-19 will have a long-lasting impact on the environmental health field and will open new research perspectives and policy needs. 相似文献
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