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David J. Tonjes James H. Heil John A. Black 《Ground Water Monitoring & Remediation》1995,15(2):134-139
Stiff diagrams arc a multivariate method of analysis used to describe the chemical state of ground water. The use of Stiff diagrams to describe multiconstituent contamination sites, such as landfills, has distinct advantages over single constituent analyses. Problems associated with traditional Stiff diagram analyses, such as diagram attentuation, can be addressed by allowing the scale of the diagram to vary with the ionic strength of the analyzed sample. The use of these sliding scale Stiff diagrams reveals the chemical slate of the ground water over wide ranges of constituent concentrations and thus allows for sensitive and sophisticated depictions of complicated contamination sites in a fashion that is extremely difficult to replicate with single constituent analyses. This approach has possible applications for understanding and tracing the mixing and chemical changes in uncontaminated settings. 相似文献
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The long-term ice record (from 1964 to 2008) of an Arctic lake in northern Europe (Lake Kilpisj?rvi) reveals the response of lake ice to climate change at local and regional scales. Average freeze-up and ice breakup occurred on 9 November and 19 June, respectively. The freeze-up has been significantly delayed at a rate of 2.3 d per decade from 1964 onward (P?<?0.05). No significant change has taken place in ice breakup. Annual average ice thickness has become smaller since the mid-1980s (P?<?0.05). Air temperature during the early ice season significantly affected the ice thickness. The freeze-up date exhibits the highest correlation with the 2-month average daily minimum air temperature centered at the end of October, while the ice breakup date exhibits the highest correlation with the 2-month average daily maximal air temperature centered in mid May. A 1°C increase in the surface air temperature corresponds to a freeze-up later by 3.4?days and an ice breakup earlier by 3.6?days. Snow cover is a critical factor in lake-ice climatology. For cumulative November to March precipitation of less than 0.13?m, the insulating effect of the snow dominated, while higher rates of precipitation favored thicker ice due to the formation of snow ice. Variations in ice records of Lake Kilpisj?rvi can serve as an indicator of climate variations across the northern Europe. The North Atlantic Oscillation (NAO) does not significantly affect the ice season there, although both the local air temperatures and winter precipitation contain a strong NAO signal. 相似文献
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L. M. Heil S. Vaughan T. P. Roberts 《Monthly notices of the Royal Astronomical Society》2009,397(2):1061-1072
We present results from a study of short-term variability in 19 archival observations by XMM–Newton of 16 ultraluminous X-ray sources (ULXs). Eight observations (six sources) showed intrinsic variability with power spectra in the form of either a power-law or broken power-law-like continuum and in some cases quasi-periodic oscillations (QPOs). The remaining observations were used to place upper limits on the strength of possible variability hidden within. Seven observations (seven sources) yielded upper limits comparable to, or higher than, the values measured from those observations with detectable variations. These represented the seven faintest sources, all with fx < 3 × 10−12 erg cm−2 s−1 . In contrast, there are four observations (three sources) that gave upper limits significantly lower than both the values measured from the ULX observations with detectable variations, and the values expected by comparison with luminous Galactic black hole X-ray binaries (BHBs) and active galactic nuclei (AGN) in the observed frequency bandpass (10−3 –1 Hz). This is the case irrespective of whether one assumes characteristic frequencies appropriate for a stellar mass (10 M⊙ ) or an intermediate mass (1000 M⊙ ) black hole, and means that in some ULXs the variability is significantly suppressed compared to bright BHBs and AGN. We discuss ways to account for this unusual suppression in terms of both observational and intrinsic effects and whether these solutions are supported by our results. 相似文献
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Claire Granier Bertrand Bessagnet Tami Bond Ariela D��Angiola Hugo Denier van der Gon Gregory J. Frost Angelika Heil Johannes W. Kaiser Stefan Kinne Zbigniew Klimont Silvia Kloster Jean-Fran?ois Lamarque Catherine Liousse Toshihiko Masui Frederik Meleux Aude Mieville Toshimasa Ohara Jean-Christophe Raut Keywan Riahi Martin G. Schultz Steven J. Smith Allison Thompson John van Aardenne Guido R. van der Werf Detlef P. van Vuuren 《Climatic change》2011,109(1-2):163-190
Several different inventories of global and regional anthropogenic and biomass burning emissions are assessed for the 1980?C2010 period. The species considered in this study are carbon monoxide, nitrogen oxides, sulfur dioxide and black carbon. The inventories considered include the ACCMIP historical emissions developed in support of the simulations for the IPCC AR5 assessment. Emissions for 2005 and 2010 from the Representative Concentration Pathways (RCPs) are also included. Large discrepancies between the global and regional emissions are identified, which shows that there is still no consensus on the best estimates for surface emissions of atmospheric compounds. At the global scale, anthropogenic emissions of CO, NOx and SO2 show the best agreement for most years, although agreement does not necessarily mean that uncertainty is low. The agreement is low for BC emissions, particularly in the period prior to 2000. The best consensus is for NOx emissions for all periods and all regions, except for China, where emissions in 1980 and 1990 need to be better defined. Emissions of CO need better quantification in the USA and India for all periods; in Central Europe, the evolution of emissions during the past two decades needs to be better determined. The agreement between the different SO2 emissions datasets is rather good for the USA, but better quantification is needed elsewhere, particularly for Central Europe, India and China. The comparisons performed in this study show that the use of RCP8.5 for the extension of the ACCMIP inventory beyond 2000 is reasonable, until more global or regional estimates become available. Concerning biomass burning emissions, most inventories agree within 50?C80%, depending on the year and season. The large differences between biomass burning inventories are due to differences in the estimates of burned areas from the different available products, as well as in the amount of biomass burned. 相似文献
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Zusammenfassung Der NW-Flügel der Nahe-Mulde wird durch die Hunsrücksüdrandstörungszone geprägt. Dieses Lineament erstreckt sich vom SE-Rand des Taunus über die Nahe- und Prims-Mulde und das Saargebiet bis nach Frankreich, wo es in die Metzer Störung übergeht. Im Arbeitsgebiet reicht die Verwerfung in große Tiefen hinab und verwirft noch die Moho.Zwischen Münster-Sarmsheim und Argenschwang ist das Devon auf das Rotliegende aufgeschoben. Von Allenfeld an nach SW ändert sich der Charakter der Störungszone. Sie spaltet in zwei bzw. drei streichende Verwerfungen auf, wodurch die beschriebene Schollengliederung des Arbeitsgebietes entsteht.Die NW-Scholle lagert diskordant auf dem varistischen Gebirge mit einem Einfallen von max. 20° SE. Sie wird vom NW-Ast der Hunsrücksüdrandstörungszone nach SE begrenzt. Im Abschnitt Argenschwang/Hochstetten schlieBt sich eine Grabenscholle an. In ihr lagern sowohl Gesteine des Unter- wie des Oberrotliegenden. Im Abschnitt Hochstetten/Kirn trennt der NW-Ast der Hunsrücksüdrandstörungszone die NW-Scholle von der Zentralscholle, die relativ gehoben erscheint. SE der SE-Grabenrandverwerfung bzw. der Störung SE der Zentralscholle des Abschnittes Hochstetten/Kirn, folgt eine gefaltete Zone.Durch eine Störung getrennt, schlieBt sich nach SE eine Scholle an, auf der die Schichten zunächst mit 60° SE einfallen. In Richtung auf die Muldenachse der Nahe-Mulde biegen sie zu flacher Lagerung um. Der Bereich um Kirn ist durch die zahlreichen Magmatite geprägt, die in enger Verbindung zur Tektonik stehen.Eine tektonische Aktivität ist nach Ablagerung der Lebacher- bzw. der Tholeyer Gruppe möglich. Die Hauptbewegungsphase fällt in das Oberrotliegende. Es entfällt die Saalische Phase mit ihrer Diskordanz zwischen Unter- und Oberrotliegendem. Lokale Diskordanzen sind auf die Intrusionstektonik zurückzuführen. Die endgültige Ausgestaltung der Nahe-Mulde dürfte wahrend der Pfälzischen Phase der varistischen Gebirgsbildung erfolgt sein.Die Querstörungen sind jünger als alle streichenden Elemente. Teilweise haben sie tertiäres Alter. Zu dieser Zeit ist vermutlich die Aufschiebung des Devons auf das Rotliegende im Abschnitt Argenschwang/Hochstetten erfolgt. Rezente Bewegungen lassen sich bis in die heutige Zeit an Hand von Erdbeben nachweisen. Die Antwort nach der Ursache der tektonischen Bewegungen bleibt spekulativ. Bei der Größe dieses Lineaments muß man jedoch an eine Plattengrenze denken.
The NW-side of the Nahe-Mulde (tray) is characterized by a fault zone at the southern rim of the Hunsrück-mountains (= Hunsrücksüdrandstörungszone = HRS). This lineament extends from the SE-periphery of the Taunus-mountains over the Nahe-Mulde and the Prims-Mulde and the Saar-district up to France, where it passes into the Metz-disturbance. In this range the faulting reaches great depths and also faults the Moho.The treated part of the HRS between Münster-Sarmsheim and Kirn an der Nahe shows a division into three parts from NE to SW. Between Münster-Sarmsheim and Argenschwang the Devonian is faulted up onto the Rotliegendes (Lower Permian). Between Argenschwang and Allenfeld the character of the faulting zone changes. It is divided into two resp. three fault strikes by what the described block division of this range results.In the area Argenschwang/Hochstetten and Hochstetten/Kirn the NW-block is deposited discordantly on the variscan formation with a maximum dip of 20° SE. It is limited to the SE by the NW-branch of the HRS. Adjacent to this lies a grabenblock in the area Argenschwang/Hochstetten. There we find rocks of the Lower as of the Upper-Rotliegenden. In the area Hochstetten-Kirn, the NW-branch of the HRS divides the NW-block from the central block, which seems to be relatively emerged. A folded zone follows in the SE of the SE-marginal graben rim fault resp. of the disturbance in the SE of the central block of the area Hochstetten/Kirn. This zone is closely locked to the SE-branch of the HRS and does not reach beyond it in the NW. Another block is adjecant to this in the SE and divided from it by a disturbance. Next to it the layers dip 60° SE and bend to a flat bedding near the axis of the Nahe-Mulde. The area around Kirn is characterized by numerous magmatic rocks, closely connected to the tectonic structures.Already structured in the Carboniferous, the HRS first represents the dividing element between the sedimentation area of the Saar-Nahe-depression and the variscan mountains. In the Lower-Rotliegendes the sedimentation then reaches beyond the fault and the Permian material is deposited discordantly on the folded Devonian.A tectonic activity is possible after the deposition of the Lebacher-resp. the Tholeyergroup. The main movements however happened within the Oberrotliegendes. Here the today identifiable longitudinal disturbances with all their phenomenas as grahen genesis, folding and intrusions are formed. The Saalische Phase with its discordance between Unter- and Oberrotliegendem is inapplicable, because the last one is concordantly following. Local discordances are explained by intrusion tectonics.The final shopping of the Nahe-Mulde might be a result of the Pfälzische Phase of the variscian orogenesis.The crossfaults were later than all the longitudinal elements.In some cases they have tertiary age. At this time also the upfaulting of the Devonian on the Rotliegendes in the part Argenschwang/Hochstetten took place. Up to our time recent movements are provable on the basis of earthquakes. Considering the dimension of this lineament one however has to be thougth of a plate boundary. However, it remains to further investigations to show this with security.
Résumé Le côte NW de la dépression de la Nahe est marquée par la »Hunsrücksüdrandstörungszone«. Ce linéament s'étend du bord SE du Taunus, par la dépression de la Nahe et du Prims et le Saargebiet jusqu'en France, où il passe à la faille de Metz. Dans la région de ce travail, le rejet s'étend jusqu'aux grandes profondeurs et déplace encore la Moho.Pour le segment traité de la »Hunsrücksüdrandstörungszone« entre Münster-Sarmsheim et Kirn an der Nahe il en résulte une structure en trois sections du NE au SW. Entre Münster-Sarmsheim et Argenschwang le Dévonien est refoulé sur le Permien. A partir de Allenfeld et dans la direction SW, le caractère de la zone dérangée change. Elle se scinde en deux ou bien trois failles longitudinales, par lesquelles se forme la structure décrite du bloc de la région.Dans les segments Argenschwang/Hochstetten et Hochstetten/Kirn, le bloc NW étudiée repose d'une façon discordante sur le terrain varistique avec un pendage de 20° SE maximum. Il est limité dans la direction du SE par la branche NW de la »Hunsrücksüdrandstörungszone«. Dans le segment Argenschwang/Hochstetten se joint le massif affaissé. A l'intérieur de celui-ci, il y a, aussi bien des roches du »Unter«-que du »Oberrotliegendem«. Dans le segment Hochstetten/Kirn, la branche NW de la »Hunsrücksüdrandstörungszone« sépare le bloc-NW du bloc central qui se montre relativement élevé. Au SE la faille marginale SE du graben ou bien de la faille SE du bloc central du segment Hochstetten/Kirn, suit une zone plissée. Cette zone est liée très étroitement à la branche-SE de la »Hunsrücksüdrandstörungszone« et ne la sillit pas dans le NW. A la zone plissée et séparée par une faille, se joint un blov vers le SE, sur lequel les strates inclinent d'abord de 60°. Dans la direction de l'axe synclinal du Nahe-mulde, elles s'incurvent et prennent une faibel inclinaison. Le segment de Kirn est marqué de nombreuses magmatites qui sont en relation étroite avec la tectonique.Déjà structurée au carbonifêre, la »Hunsrücksüdrandstörungszone« représente 1'élément séparant l'aire sedimentaire de la Saar-Nahe-Senke et le terrain varistique. Dans le »Unterrotliegendem« la sédimentation s'entend au delá de la faille et la Permien repose en discordance.Une véritable activité tectonique est possible après la sédimentation du groupe Lebacher ou du groupe Tholeyer. La phase principale est cependant dans le »Oberrotliegende«. Ici se forment les failles longitudinales, aujoud'hui reconniassables, avec tous leurs phénomènes, comme formation de fosses tectoniques, plis et instrusions. La »Saalische« phase avec sa discordance entre »Unter«- et »Oberrotliegendem« échappe, parce que ce dernier est déposé de façon concordante sur les roches de base. On peut ramener les discordances locales à la tectonique de l'intrusion. La formation définitive pourrait avoir lieu pendant la »Pfälzische Phase« de l'orogénèse varistique.Les failles transversales sont plus jeunes que tous les éléments longitudinaux. Elles sont en partie d'âge sou-tertiare. Le lévement du Dévonien sur le Permien dans le segment Argenschwang/Hochstetten s'est vraissemblablement produit à cette époque. Des mouvements récents se laissent démontrer jusqu'à nos jours au moyen des tremblements de terre. La réponse a la cause des mouvements reste spéculative. Cependant, en voyant la grandeur de ce linéament, on doit penser à une limite de plaque. Cette réalité nécessiterait toute fois d'autres recherches.
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K. Mannschreck K. Bächmann K. H. Becker Th. Heil R. Kurtenbach M. Memmesheimer V. Mohnen A. Obermeier D. Poppe R. Steinbrecher Th. Schmitz A. Volz-Thomas F. Zabel 《Journal of Atmospheric Chemistry》2002,42(1):281-286
The database for volatile organic compounds (VOC data base) was created with the aim of providing an overview of tropospheric hydrocarbon measurements. The data base contains 202 substances, for which atmospheric and useful kinetic data such as rate coefficients, photolysis frequencies, mixing ratios, emission data and ozone formation potentials are compiled from available literature. The database file can be downloaded without charge from http://www.physchem.uni-wuppertal.de/voc-database. Registered users will be informed about the appearance of updates. 相似文献
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Patricia M. Glibert Cynthia A. Heil Judith M. O'Neil William C. Dennison Mark J. H. O'Donohue 《Estuaries and Coasts》2006,29(2):209-221
Subtropical estuaries have received comparatively little attention in the study of nutrient loading and subsequent nutrient
processing relative to temperate estuaries. Australian estuaries are particularly susceptible to increased nutrient loading
and eutrophication, as 75% of the population resides within 200 km of the coastline. We assessed the factors potentially limiting
both biomass and production in one Australian estuary, Moreton Bay, through stoichiometric comparisons of nitrogen (N), phosphorus
(P), silicon (Si), and carbon (C) concentrations, particulate compositions, and rates of uptake. Samples were collected over
3 seasons in 1997–1998 at stations located throughout the bay system, including one riverine endmember site. Concentrations
of all dissolved nutrients, as well as particulate nutrients and chlorophyll, declined 10-fold to 100-fold from the impacted
western embayments to the eastern, more oceanic-influenced regions of the bay during all seasons. For all seasons and all
regions, both the dissolved nutrients and particulate biomass yielded N:P ratios <6 and N:Si ratios <1. Both relationships
suggest strong limitation of biomass by N throughout the bay. Limitation of rates of nutrient uptake and productivity were
more complex. Low C:N and C:P uptake ratios at the riverine site suggested light limitation at all seasons, low N:P ratios
suggested some degree of N limitation and high N:Si uptake ratios in austral winter suggested Si limitation of uptake during
that season only. No evidence of P limitation of biomass or productivity was evident. 相似文献
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J.J. Walsh C.R. TomasK.A. Steidinger J.M. LenesF.R. Chen R.H. WeisbergL. Zheng J.H. LandsbergG.A. Vargo C.A. Heil 《Continental Shelf Research》2011,31(9):891-911
Within the context of ubiquitous overfishing of piscivores, recent consequent increments of jellyfish and clupeids have occurred at the zooplanktivore trophic level in the eastern Gulf of Mexico (GOM), after overfishing of one of their predators, i.e. red snapper. Initiation of a local trophic cascade thence led to declines of herbivore stocks, documented here on the West Florida shelf. These exacerbating world-wide trophic cascades have resulted in larger harmful algal blooms (HABs), already present at the base of most coastal food webs. Impacts on human health have thus far been minimal within nutrient-rich coastal regions. To provide a setting for past morbidities, consideration is given to chronologies of other trophic cascades within eutrophic, cold water marine ecosystems of the Scotian Sea, in the Gulf of Alaska, off Southwest Africa, within the Barents, White, and Black Seas, in the Gulf of Maine, and finally in the North Sea. Next, comparison is now made here of recent ten-fold increments within Florida waters of both relatively benign and saxitoxic HABs, some of which are fatal to humans. These events are placed in a perspective of other warm shelf systems of the South China and Caribbean Seas to assess prior and possible future poison toxicities of oligotrophic coastal habitats. Past wide-spread kills of fishes and sea urchins over the Caribbean Sea and the downstream GOM are examined in relation to the potential transmission of dinoflagellate saxitoxin and other epizootic poison vectors by western boundary currents over larger “commons” than local embayments. Furthermore, since some HABs produce more potent saxitoxins upon nutrient depletion, recent decisions to ban seasonal fertilizer applications to Florida lawns may have unintended consequences. In the future, human-killing phytoplankton, rather than relatively benign fish-killing HABs of the past, may be dispersed along the southeastern United States seaboard. 相似文献