Effects of pollen leaching and microbial degradation on organic carbon and nutrient availability in lake water     

Stefan?R?sel  Anna?Rych?a  Christian?Wurzbacher  Hans-Peter?GrossartEmail author 《Aquatic Sciences - Research Across Boundaries》2012,74(1):87-99

Nutrient fluxes across terrestrial-aquatic boundaries and their subsequent integration into lake nutrient cycles are currently a major topic of aquatic research. Although pollen represents a good substrate for microorganisms, it has been neglected as a terrestrial source of organic matter in lakes. In laboratory experiments, we incubated pollen grains of Pinus sylvestris in water of lakes with different trophy and pH to estimate effects of pollen input and its subsequent microbial degradation on nutrient dynamics. In this ex situ experiment, we measured concentrations of organic carbon, phosphorus and nitrogen in the surrounding water as well as microbial dynamics (bacteria and fungal sporangia) at well-controlled conditions. Besides leaching, chemical and microbial decomposition of pollen was strongest within the first week of incubation. This led to a marked increase of soluble reactive phosphorus and total dissolved nitrogen (up to 0.04 and 1.5 mg L⁻¹, respectively, after 5 days of incubation) in the ambient water. In parallel, pollen grains were rapidly colonized by heterotrophic bacteria and aquatic fungi. Leaching and microbial degradation of pollen accounted for ≥80, ≥40, ≥50% for organic C, N and P, respectively, and did not significantly differ among water samples from the studied lakes. Thus, pollen introduces high amounts of bio-available terrestrial organic matter and nutrients into surface waters within a short time. A rough calculation on P input into oligotrophic Lake Stechlin indicates that pollen plays an important ecological role in nutrient cycling of temperate lakes. This requires further attention in aquatic ecology.  相似文献   

GPS for real-time earthquake source determination and tsunami warning systems   总被引：1，自引：0，他引：1  

Geoffrey Blewitt  William C. Hammond  Corné Kreemer  Hans-Peter Plag  Seth Stein  Emile Okal 《Journal of Geodesy》2009,83(3-4):335-343

We identify the key design aspects of a GPS-based system (and in the future, GNSS-based systems) that could contribute to real-time earthquake source determination and tsunami warning systems. Our approach is based on models of both transient and permanent displacement of GPS stations caused by large earthquakes, while considering the effect of GPS errors on inverted earthquake source parameters. Our main conclusions are that (1) the spatial pattern, magnitude, and timing of permanent displacement of GPS stations can be inverted for the earthquake source and so predict the 3D displacement field of the ocean bottom, thus providing the initial conditions for tsunami models, and (2) there are no inherently limiting factors arising from real-time orbit and positioning errors, provided sufficient near-field GPS stations are deployed. This signal could be readily exploited by GPS networks currently in place, and will be facilitated by the IGS Real-Time Project as it comes to fruition.  相似文献   

Das Verhältnis TiO2 : Fe in westnorwegischen Magn etit-Ilmeniterzen     

Dr. Hans-Peter Geis 《International Journal of Earth Sciences》1966,55(2):414-417

Zusammenfassung In Westnorwegen auftretende Magnetit-Ilmeniterze sind teilweise an intrusive, gabbroide Gesteine und teilweise an wahrscheinlich extrusive Amphibolite gebunden. Das TiO₂Fe-Verhältnis der Amphiboliterze beträgt 0,14–0,15 und ist innerhalb der einzelnen Vorkommen konstant. In den Gabbroerzen liegt das Verhältnis zwischen 0,21 und 0,35 und schwankt auch innerhalb der Einzelvorkommen stark.

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Magnetite-ilmenite ore in western Norway occurs partly in intrusive, gabbroic rocks, partly in amphibolites which seem to be extrusive. The relation TiO₂: Fe in the amphibolite ores is 0.14–0.15 and is constant within every deposit. In the gabbro ores the relation TiO₂Fe lies between 0.21 and 0.35 and varies also within every single deposit.

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Résumé Dans l'Ouest de la Norvège des gisements de magnétite-ilménite se trouvent en partie dans des roches gabbroïques et intrusives, en partie dans des amphibolites qui sont probablement extrusives. Le rapport TiO₂Fe dans les minerais amphibolitiques est de 0,14–0,15 et se montre très constant d'un gisement à l'autre. Dans les minerais gabbroïques, le rapport TiO₂Fe varie entre 0,21 et 0,35 et diffère selon le gisement.

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. TiO₂: Fe .

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Die Stellung der nordnorwegischen Eisenerzlagerstätte Andörja in der kaledonischen Geosynklinale     

Dr. Hans-Peter Geis 《International Journal of Earth Sciences》1967,56(1):561-567

Zusammenfassung Die Magnetiterzlager der Insel Andörja/Nordnorwegen liegen in einer Serie mesozonal metamorphisierter Sedimente des Kambro-Silurs der Kaledoniden: Granatglimmerschiefer Hangender Kalkmarmor (max. 5 Horizonte, die bis 9 m mächtig sind) Amphibolitschiefer (83–175 m mächtig, mit marin-sedimentären Magnetiterzen) Liegender Kalkmarmor (0–4 m mächtig) Granatglimmerschiefer, z. T. Quarzit.Diese Gesteinsfolge hat typisch miogeosynklinalen Charakter. Da sie westlich des Verbreitungsgebiets der eugeosynklinalen kaledonischen Sedimente und nahe dem Westrand des Verbreitungsgebiets kambro-silurischer Gesteine überhaupt auftritt, könnte es sich hier um den Westrand der Kaledoniden handeln. Westlich davon auftretende präkaledonische Gesteine könnten dann zur irischen Plattform gehören.

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The magnetite layers on the island of Andörja lie in a series of metamorphosed cambro-silurian sediments with the following sequence: garnet mica schist upper marble (max. 5 layers with up to 5 m thickness) amphibolite schist (83–175 m thickness, with marine sedimentary magnetite ore) lower marble (0–4 m thickness) garnet mica schist, partly quartzite.This rock sequence is of typically miogeosynclinal character. As it is situated to the west of the extension of the eugeosynclinal Caledonian rocks and near the western border of the cambro-silurian rocks on the whole, we might have here the western boundary of the caledonian geosyncline. Precaledonian rocks to the west of Andörja might then belong to the Irish platform.

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Résumé Les couches de magnétite du gisement d'Andörja se trouvent dans une série de sediments cambro-siluriens métamorphiques avec la séquence suivante: marbre supérieur (max. 5 horizons qui ont une épaisseur jusqu'à 9 m) amphibolite (83–175 m d'épaisseur, avec gisements de magnétite) marbre inférieur (0–4 m d'épaisseur) schistes de grenat et mica, en partie quartzites.La séquence est d'un caractère typiquement miogeosynclinal. Parce qu'elle apparaît à l'ouest de l'extension des roches eugéosynclinales calédoniennes et à la bordure des roches cambro-siluriennes en général, on y a probablement la frontière occidentale de la géosynclinale calédonienne. Les roches précalédoniennes plus à l'ouest pourraient alors appartenir à la plateforme d'Irlande.

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Andörja ( ), - : (9 ), (83–175 , ), (0–4 ), - , . . , .

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Chemical Mechanism Development: Laboratory Studies and Model Applications     

Harald Geiger  Ian Barnes  Karl H. Becker  Birger Bohn  Theo Brauers  Birgit Donner  Hans-Peter Dorn  Manfred Elend  Carlos M. Freitas Dinis  Dirk Grossmann  Heinz Hass  Holger Hein  Axel Hoffmann  Lars Hoppe  Frank Hülsemann  Dieter Kley  Björn Klotz  Hans G. Libuda  Tobias Maurer  Djuro Mihelcic  Geert K. Moortgat  Romeo Olariu  Peter Neeb  Dirk Poppe  Lars Ruppert  Claudia G. Sauer  Oleg Shestakov  Holger Somnitz  William R. Stockwell  Lars P. Thüner  Andreas Wahner  Peter Wiesen  Friedhelm Zabel  Reinhard Zellner  Cornelius Zetzsch 《Journal of Atmospheric Chemistry》2002,42(1):323-357

Within the German Tropospheric Research Programme (TFS) numerous kinetic and mechanistic studies on the tropospheric reaction/degradation of the following reactants were carried out: oxygenated VOC, aromatic VOC, biogenic VOC, short-lived intermediates, such as alkoxy and alkylperoxy radicals.At the conception of the projects these selected groups were classes of VOC or intermediates for which the atmospheric oxidation mechanisms were either poorly characterised or totally unknown. The motivation for these studies was the attainment of significant improvements in our understanding of the atmospheric chemical oxidation processes of these compounds, particularly with respect to their involvement in photooxidant formation in the troposphere. In the present paper the types of experimental investigations performed and the results obtained within the various projects are briefly summarised. The major achievements are highlighted and discussed in terms of their contribution to improving our understanding of the chemical processes controlling photosmog formation in the troposphere.  相似文献   

The GGOS as the backbone for global observing and local monitoring: A user driven perspective   总被引：1，自引：0，他引：1  

H.-P. Plag   《Journal of Geodynamics》2005,40(4-5):479

A key geodetic contribution to both the three Global Observing Systems and initiatives like the European Global Monitoring for Environment and Security is an accurate, long-term stable, and easily accessible reference frame as the backbone. Many emerging scientific as well as non-scientific high-accuracy applications require access to an unique, technique-independent reference frame decontaminated for short-term fluctuations due to global Earth system processes. Such a reference frame can only be maintained and made available through an observing system such as the Global Geodetic Observing System (GGOS), which is currently implemented and expected to provide sufficient information on changes in the Earth figure, its rotation and its gravity field. Based on a number of examples from monitoring of infrastructure, point positioning, maintenance of national references frames to global changes studies, likely future accuracy requirements for a global terrestrial reference frame are set up as function of time scales. Expected accuracy requirements for a large range of high-accuracy applications are less than 5 mm for diurnal and sub-diurnal time scales, 2–3 mm on monthly to seasonal time scales, better than 1 mm/year on decadal to 50 years time scales. Based on these requirements, specifications for a geodetic observing system meeting the accuracy requirements can be derived.  相似文献   

Mantle circulation models with variational data assimilation: inferring past mantle flow and structure from plate motion histories and seismic tomography   总被引：3，自引：0，他引：3  

Hans-Peter Bunge  C. R. Hagelberg  B. J. Travis 《Geophysical Journal International》2003,152(2):280-301

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From drought to flood: A water balance analysis of the Tuolumne River basin during extreme conditions (2015–2017)     

Andrew R. Hedrick  Danny Marks  Hans-Peter Marshall  James McNamara  Scott Havens  Ernesto Trujillo  Micah Sandusky  Mark Robertson  Micah Johnson  Kat J. Bormann  Thomas H. Painter 《水文研究》2020,34(11):2560-2574

The degree to which the hydrologic water balance in a snow-dominated headwater catchment is affected by annual climate variations is difficult to quantify, primarily due to uncertainties in measuring precipitation inputs and evapotranspiration (ET) losses. Over a recent three-year period, the snowpack in California's Sierra Nevada fluctuated from the lightest in recorded history (2015) to historically heaviest (2017), with a relatively average year in between (2016). This large dynamic range in climatic conditions presents a unique opportunity to investigate correlations between annual water availability and runoff in a snow-dominated catchment. Here, we estimate ET using a water balance approach where the water inputs to the system are spatially constrained using a combination of remote sensing, physically based modelling, and in-situ observations. For all 3 years of this study, the NASA Airborne Snow Observatory (ASO) combined periodic high-resolution snow depths from airborne Lidar with snow density estimates from an energy and mass balance model to produce spatial estimates of snow water equivalent over the Tuolumne headwater catchment at 50-m resolution. Using observed reservoir inflow at the basin outlet and the well-quantified snowmelt model results that benefit from periodic ASO snow depth updates, we estimate annual ET, runoff efficiency (RE), and the associated uncertainty across these three dissimilar water years. Throughout the study period, estimated annual ET magnitudes remained steady (222 mm in 2015, 151 mm in 2016, and 299 mm in 2017) relative to the large differences in basin input precipitation (547 mm in 2015, 1,060 mm in 2016, and 2,211 mm in 2017). These values compare well with independent satellite-derived ET estimates and previously published studies in this basin. Results reveal that ET in the Tuolumne does not scale linearly with the amount of available water to the basin, and that RE primarily depends on total annual snowfall proportion of precipitation.  相似文献   

Exploring high-end scenarios for local sea level rise to develop flood protection strategies for a low-lying delta—the Netherlands as an example   总被引：4，自引：1，他引：3  

Caroline A. Katsman  A. Sterl  J. J. Beersma  H. W. van den Brink  J. A. Church  W. Hazeleger  R. E. Kopp  D. Kroon  J. Kwadijk  R. Lammersen  J. Lowe  M. Oppenheimer  H. -P. Plag  J. Ridley  H. von Storch  D. G. Vaughan  P. Vellinga  L. L. A. Vermeersen  R. S. W. van de Wal  R. Weisse 《Climatic change》2011,109(3-4):617-645

Sea level rise, especially combined with possible changes in storm surges and increased river discharge resulting from climate change, poses a major threat in low-lying river deltas. In this study we focus on a specific example of such a delta: the Netherlands. To evaluate whether the country’s flood protection strategy is capable of coping with future climate conditions, an assessment of low-probability/high-impact scenarios is conducted, focusing mainly on sea level rise. We develop a plausible high-end scenario of 0.55 to 1.15 m global mean sea level rise, and 0.40 to 1.05 m rise on the coast of the Netherlands by 2100 (excluding land subsidence), and more than three times these local values by 2200. Together with projections for changes in storm surge height and peak river discharge, these scenarios depict a complex, enhanced flood risk for the Dutch delta.  相似文献   

Pink manganian phengite in a high P/T meta-conglomerate from northern Syros (Cyclades, Greece)     

Rainer Altherr  Christian Soder  Sandra Panienka  Daniel Peters  Hans-Peter Meyer 《Contributions to Mineralogy and Petrology》2013,166(5):1323-1334

A new occurrence of Mn-rich rocks was discovered within the high-pressure/low-temperature metamorphic rocks on the Palos peninsula of Syros (Greece). Near the summit of Mount Príonas, a meta-conglomerate consists of calcite (~63 wt%), pink manganian phengite, blue–purple manganian aegirine–jadeite, microcline, albite and quartz. In addition, it contains abundant braunite-rich aggregates (up to ~1.5 cm in diameter) that include hollandite [(Ba_0.98–1.02K_<0.01Na_<0.02Ca_<0.03) (Mn _1.02–1.52 ³⁺ Fe _0.38–0.88 ³⁺ Ti_0.29–0.92Mn _5.11–5.76 ⁴⁺ )O₁₆], barite and manganian hematite. Due to metamorphic recrystallization and deformation, the contacts between clasts and matrix are blurred and most clasts have lost their identity. In back-scattered electron images, many aegirine–jadeite grains appear patchy and show variable jadeite contents (Jd_10–67). These pyroxenes occur in contact with either quartz or albite. Manganian phengite (3.41–3.49 Si per 11 oxygen anions) is of the 3T type and contains 1.4–2.2 wt% of Mn₂O₃. At the known P–T conditions of high-pressure metamorphism on Syros (~1.4 GPa/ 470 °C), the mineral sub-assemblage braunite + quartz + calcite (former aragonite) suggests high oxygen fugacities relative to the HM buffer (+7 ≤ ?f_O2 ≤ + 17) and relatively high CO₂ fugacities. The exact origin of the conglomerate is not known, but it is assumed that the Fe–Mn-rich and the calcite-rich particles originated from different sources. Braunite has rather low contents of Cu (~0.19 wt%) and the concentrations of Co, Ni and Zn are less than 0.09 wt%. Hollandite shows even lower concentrations of these elements. Furthermore, the bulk-rock compositions of two samples are characterized by low contents of Cu, Co and Ni, suggesting a hydrothermal origin of the manganese ore. Most likely, these Fe–Mn–Si oxyhydroxide deposits consisted of ferrihydrite, todorokite, birnessite, amorphous silica (opal-A) and nontronite. Al/(Al + Fe + Mn) ratios of 0.355 and 0.600 suggest the presence of an aluminosilicate detrital component.  相似文献