Hannover, Germany
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Spielmeyer A.,Justus Liebig University | Hoper H.,State Authority for Mining | Hamscher G.,Justus Liebig University
Chemosphere | Year: 2017

Veterinary antibiotics such as sulfonamides are frequently applied in livestock farming worldwide. Due to poor absorption in the animal gut and/or reversible metabolization sulfonamides are excreted in considerable amounts and can subsequently be detected in liquid manure. As manure is utilized for soil fertilization, sulfonamides can enter the environment via this pathway. Water samples taken below an agriculture field in Lower Saxony revealed the permanent entrance of sulfamethazine into groundwater and concentrations up to 100 ng L−1 were determined. During a long-term lysimeter study, nine sulfonamides were applied to two different soil types by using fortified liquid manure. Divert mobilities were found with sulfamethazine und sulfamethoxazole showing the highest detection frequency in water samples taken below both bedrock and sandy soil. Four years after the last application of fortified manure, sulfonamides were still detectable in the leachate. Based on analyses of manure and fermentation residue samples, a permanent input of sulfonamides to the soil can be excluded. Thus, the positive findings must be caused by the antibiotics once applied. Soils fertilized with manure contaminated with sulfonamides can consequently be a long-time source for the transfer of antibiotics into groundwater. © 2017 Elsevier Ltd


Richoz S.,Goethe University Frankfurt | Richoz S.,Austrian Academy of Sciences | Van De Schootbrugge B.,Goethe University Frankfurt | Pross J.,Goethe University Frankfurt | And 10 more authors.
Nature Geoscience | Year: 2012

The evolution of complex life over the past 600 million years was disrupted by at least five mass extinctions, one of which occurred at the close of the Triassic period. The end-Triassic extinction corresponds to a period of high atmospheric-CO 2 concentrations caused by massive volcanism and biomass burning; most extinction scenarios invoke the resulting environmental perturbations in accounting for the loss of marine and terrestrial biodiversity. Here we reconstruct changes in Tethyan shallow marine ecosystems and ocean redox chemistry from earliest Jurassic (Hettangian)-aged black shales from Germany and Luxemburg. The shales contain increased concentrations of the biomarker isorenieratane, a fossilized pigment from green sulphur bacteria. The abundance of green sulphur bacteria suggests that the photic zone underwent prolonged periods of high concentrations of hydrogen sulphide. This interval is also marked by the proliferation of green algae, an indicator of anoxia. We conclude that the redox changes in the entire water column reflect sluggish circulation in marginal regions of the Tethys Ocean. We suggest that the resultant repeated poisoning of shallow epicontinental seasg-hotspots of Mesozoic biodiversityg-with hydrogen sulphide may have slowed the recovery of marine ecosystems during the Early Jurassic. © 2012 Macmillan Publishers Limited. All rights reserved.


Klimke J.,Leibniz University of Hanover | Klimke J.,Federal Institute for Geosciences and Natural Resources | Wiederhold H.,Leibniz Institute for Applied Geophysics | Winsemann J.,Leibniz University of Hanover | And 2 more authors.
Zeitschrift der Deutschen Gesellschaft fur Geowissenschaften | Year: 2013

The increasing demand on using the subsurface raises the call for a better understanding of the depositional architecture. In this study, we demonstrate how 3D subsurface models can be improved by airborne electromagnetic data. The study area is located in the Pleistocene Quakenbrück Basin in Northern Germany. This overdeepened basin is fronted by a push moraine ridge and fi lled with Middle Pleistocene (Saalian) to Holocene sediments known from a limited amount of borehole data. In 2009, this area was target of an aeroelectromagnetic survey with the SkyTEM system. For the interpretation of SkyTEM resistivity data, a relation between grain size and resistivity was derived using resistivity borehole logs from the larger study area. The analysis of the data showed a positive correlation as resistivity increases with increasing grain size and permeability. Each stratigraphic layer was then modelled with the commercial software GOCAD® based on the geological and geophysical information as each sediment layer is characterised by a specifi c resistivity in the SkyTEM data. Our results demonstrate that by integrating airborne electromagnetic data into geological 3D models, the distribution of stratigraphic units can be modelled with higher lateral resolution due to higher data density. The resistivity-grain size relation can be applied to other study areas with comparable geological conditions. Saline groundwater can clearly be identifi ed and distinguished from non-saline regions in the Quakenbrück Basin by low resistivities. © 2013 E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany.


Strack O.D.L.,University of Minnesota | Stoeckl L.,Federal Institute for Geosciences and Natural Resources | Damm K.,State Authority for Mining | Houben G.,Federal Institute for Geosciences and Natural Resources | And 2 more authors.
Water Resources Research | Year: 2016

We present an approach for reducing saltwater intrusion in coastal aquifers by artificially reducing the hydraulic conductivity in the upper part of selected areas by using a precipitate. We apply a previously presented analytical approach to develop formulas useful for the design of artificial barriers. Equations for the location of the tip of the saltwater wedge are presented and verified through a sand-tank experiment. The analysis is capable of computing discharges exactly, but requires the Dupuit-Forchheimer approximation to compute points of the interface between flowing fresh and stationary saltwater. We consider a vertical coastline and boundaries in the freshwater zone of either given discharge or given head. We demonstrate in the paper that reduction of the hydraulic conductivity in the upper part of a coastal aquifer will result in a decrease of saltwater intrusion, and present analytic expressions that can be used for design purposes. The previously presented analytical approach can be applied to design systems to reduce saltwater intrusion caused by pumping inland from the zone that contains saline groundwater. © 2016. American Geophysical Union.


Acksel A.,University of Rostock | Amelung W.,University of Bonn | Kuhn P.,University of Tübingen | Gehrt E.,State Authority for Mining | And 2 more authors.
Geoderma Regional | Year: 2016

The genesis of Chernozems in the Baltic Sea region is still insufficiently understood and the composition of its organic matter may be a key for a better pedogenetic interpretation of the mollic, biogenically mixed (Axh) horizons. Therefore, we investigated the composition of soil organic matter in the Ap/Ah- and Axh-horizons from seven soil profiles at the islands of Poel, Fehmarn (Germany), and Sjalland (Denmark). In a multi-methods approach we carried out synchrotron-based X-ray absorption near edge structure (XANES) spectroscopy at the carbon (C) and nitrogen (N) K-edges, pyrolysis-field ionisation-mass spectrometry (Py-FIMS) and soil color measurements as non-specific, bulk SOM characterization methods, and quantified the benzene polycarboxylic acids (BPCAs) as specific markers for black carbon (BC). The XANES- and Py-FIMS-spectra in good agreement revealed relative enrichments of aromatic C and heterocyclic N compounds in the lower Axh- in comparison to the corresponding upper Ap/Ah-horizons. In almost all horizon pairs, the BC portions in the Axh- (7.6 to 18% of Corg) exceeded those in the Ap/Ah-horizons (6.7 to 12% of Corg) and were similar to the BC portions in typical Phaeozems and Chernozems from European loess areas. The ratios of penta- to hexacarboxylic benzoic acids (B5CA/B6CA) of 0.9 to 2.2, mean 1.2, indicated contributions of combustion residues from domestic and grassland fires. This pyrogenic organic matter and its transformation products governed the soil color, which was closely correlated to the BC portions (L∗-value = - 0.880 x + 52.13; r2 = 0.539∗∗). In summary, the enrichments of stabilized aromatic and heterocyclic compounds in the Axh-horizons derived from C- and N-XANES, Py-FIMS and the BC-determination are interpreted by an input of pyrogenic matter into the Baltic Chernozems, indicating an anthropo-pedogenesis in the period between Bronze age and the Early Middle Ages. © 2016 Elsevier B.V. All rights reserved.


Beyer C.,State Authority for Mining | Liebersbach H.,Energy and Geology | Hoper H.,State Authority for Mining
Journal of Plant Nutrition and Soil Science | Year: 2015

To date there is still a lack of reliable data on greenhouse gas emissions from drained fens needed to determine the climatic relevance of land use and land use change on peatlands and to supply the National Inventory Report for the German Greenhouse Gas Inventory. In this study we present the results of monthly-based multiyear measurements of CO2, N2O and CH4 flux rates in two drained agriculturally used fen ecosystems in NW Germany (cropland and grassland) over a period of 4.5 y using transparent and opaque closed chambers. CO2 exchange was modelled at high resolution with temperature and photosynthetic active radiation. The measured and modelled values fit very well (R2 ≥ 0.93). Annual GHG and Global Warming Potential (GWP) balances were determined. Net CO2 emissions at the cropland and grassland sites were similarly high, taking into account changes in management; net ecosystem C balance amounted to about 4.0 to 5.0 Mg C ha-1 y-1. Emissions of N2O and CH4 were low at both sites. The mean GWP balance for a time frame of 100 y (GWP100) amounted to about 17.0 to 19.0 Mg CO2-eq. ha-1 y-1. The unexpectedly low greenhouse gas emissions from the cropland site are attributed to the high water table and a change in crop management. The change from corn for silage to corn-cob mix lead transiently to rather small greenhouse gas emissions. The study confirms the need for multiyear measurements taking climatic and management variation into account. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Blumenberg M.,Federal Institute for Geosciences and Natural Resources | Heunisch C.,State Authority for Mining | Luckge A.,Federal Institute for Geosciences and Natural Resources | Scheeder G.,Federal Institute for Geosciences and Natural Resources | And 2 more authors.
Palaeogeography, Palaeoclimatology, Palaeoecology | Year: 2016

Shortly after the deposition of black shales in the Rhaetian Sea (Central European Basin, CEB), the Triassic/Jurassic (Tr/J) boundary witnessed one of the Big Five mass extinction events in Earth's history. Aiming at a better understanding of paleoenvironmental changes in the (geochemically) less well-known middle to late Rhaetian (German subdivision), we studied samples from a cored borehole from the central Rhaetian Sea in NW Germany (Hebelermeer 2). Biomarkers, palynomorphs and bulk geochemistry all support a marine/brackish setting with inputs from terrestrial plants. Dinosteranes were found throughout the core, most likely suggesting the spread of dinoflagellates. It is widely accepted that volcanic exhalations during the development of the Central Atlantic Magmatic Province (CAMP) had a major impact on marine and terrestrial environments in the earliest Jurassic e.g., the development of photic zone euxinia and H2S poisoning of benthic life. There is evidence from the studied core, however, that comparable conditions already thrived in the central Rhaetian Sea during the middle Rhaetian. A first indication of euxinia/anoxia is evident from low to very low total organic carbon versus total sulfur (TOC/TS) ratios (~<1) with a minimum preceding the Tr/J boundary (0.03). The latter very low value hints at a decoupling of S and C cycles and eventually abiogenic pyrite formation. Water-column anoxia during the middle Rhaetian is indicated by the occurrence of the biomarker gammacerane, which records ciliates living at the O2-H2S chemocline. The strongest support for a stratified water column even with photic zone euxinia comes from high abundances of isorenieratane. This biomarker is a pigment of anoxygenic phototrophic green sulfur bacteria, which use H2S for photosynthesis. Our data point to perturbations in the biogeochemical cycles of sulfur and carbon already in the middle Rhaetian, which are possibly linked to early volcanic activities and SO2, H2S, and CO2 eruptions. © 2016 Elsevier B.V.


Beyer C.,State Authority for Mining | Hoper H.,State Authority for Mining
Biogeosciences | Year: 2015

During the last decades an increasing area of drained peatlands has been rewetted. Especially in Germany, rewetting is the principal treatment on cutover sites when peat extraction is finished. The objectives are bog restoration and the reduction of greenhouse gas (GHG) emissions. The first sites were rewetted in the 1980s. Thus, there is a good opportunity to study long-term effects of rewetting on greenhouse gas exchange, which has not been done so far on temperate cutover peatlands. Moreover, Sphagnum cultivating may become a new way to use cutover peatlands and agriculturally used peatlands as it permits the economical use of bogs under wet conditions. The climate impact of such measures has not been studied yet. We conducted a field study on the exchange of carbon dioxide, methane and nitrous oxide at three rewetted sites with a gradient from dry to wet conditions and at a Sphagnum cultivation site in NW Germany over the course of more than 2 years. Gas fluxes were measured using transparent and opaque closed chambers. The ecosystem respiration (CO2) and the net ecosystem exchange (CO2) were modelled at a high temporal resolution. Measured and modelled values fit very well together. Annually cumulated gas flux rates, net ecosystem carbon balances (NECB) and global warming potential (GWP) balances were determined. The annual net ecosystem exchange (CO2) varied strongly at the rewetted sites (from g'201.7 ± 126.8 to 29.7± 112.7g CO2-C mg'2 ag'1) due to differing weather conditions, water levels and vegetation. The Sphagnum cultivation site was a sink of CO2 (g'118.8 ± 48.1 and g'78.6 ± 39.8 g CO2-C mg'2 ag'1). The annual CH4 balances ranged between 16.2 ± 2.2 and 24.2 ± 5.0g CH4-C mg'2 ag'1 at two inundated sites, while one rewetted site with a comparatively low water level and the Sphagnum farming site show CH4 fluxes close to 0. The net N2O fluxes were low and not significantly different between the four sites. The annual NECB was between g'185.5 ± 126.9 and 49.9 ± 112.8 g CO2-C mg'2 ag'1 at the rewetted sites and g'115.8 ± 48.1 and g'77 ± 39.8 g CO2-C mg'2 ag'1 at the Sphagnum cultivating site. The annual GWP100 balances ranged from g'280.5 ± 465.2 to 644.5 ± 413.6 g CO2-eq. mg'2 ag'1 at the rewetted sites. In contrast, the Sphagnum farming site had a cooling impact on the climate in both years (g'356.8 ± 176.5 and g'234.9 ± 145.9 g CO2-C mg'2 ag'1). If the carbon exported through the harvest of the Sphagnum biomass and the additional CO2 emission from the decay of the organic material is considered, the NECB and GWP100 balances are near neutral. Peat mining sites are likely to become net carbon sinks and a peat accumulating ("growing") peatland within 30 years of rewetting, but the GWP100 balance may still be positive. A recommended measure for rewetting is to achieve a water level of a few centimetres below ground. Sphagnum farming is a climate-friendly alternative to conventional commercial use of bogs. A year-round constant water level of a few centimetres below ground level should be maintained. © 2015 Author(s).


Houben G.J.,Federal Institute for Geosciences and Natural Resources | Hauschild S.,State Authority for Mining
Ground Water | Year: 2011

Numerical flow models can be a useful tool for dimensioning water wells and to investigate the hydraulics in their near-field. Fully laminar flow can be assumed for all models calculated up to the screen. Therefore models can be used to predict-at least qualitatively, neglecting turbulent losses inside the well-the spatial distribution of inflow into the well and the overall hydraulic performance of different combinations of aquifer parameters and technical installations. Models for both horizontal (plan view) and vertical flow (cross section) to wells were calculated for a variety of setups. For the latter, this included variations of hydraulic conductivity of the screen, pump position, and aquifer heterogeneity. Models of suction flow control devices showed that they indeed can homogenize inflow, albeit at the cost of elevated entrance losses. © 2010 The Author(s). Journal compilation © 2010 National Ground Water Association.


Pusch M.,Federal Institute for Geosciences and Natural Resources | Hammer J.,Federal Institute for Geosciences and Natural Resources | Kus J.,Federal Institute for Geosciences and Natural Resources | Klosa D.,State Authority for Mining | And 2 more authors.
Zeitschrift der Deutschen Gesellschaft fur Geowissenschaften | Year: 2014

In context of further exploration of the Gorleben salt dome (March 2011 to November 2012) mineralogical and geochemical investigations have been conducted on hydrocarbon-bearing samples of the "Knäuelsalz" (z2HS1), particularly the oldest part of the "Hauptsalz" (Staßfurt Series z2). Investigations focus on genesis, composition and macro-/microstructural distribution of hydrocarbons. These exploration works continue investigations of Gerling & Faber (2001) and Gerling et al. (2002). For this purpose 45 entire cored sampling boreholes supplemented with 20 packer boreholes in Crosscuts 1 West (Q1W) and 1 East (Q1E) have been drilled between March 2011 and March 2012 at the 840 m level of the Gorleben exploration mine in order to get new faultless and unaltered samples beyond the excavation damaged zone. Drill cores of hydrocarbon sampling and packer boreholes have been investigated under ultraviolet light (λ = 254 nm) for indications of the existence of fluorescent (aromatic) hydrocarbons. The results were documented and visualised in the geological 3D model of the Gorleben salt dome. Microscopical studies of thin and thick sections show that hydrocarbons were located at the grain boundaries of halite and/or anhydrite crystals, in newly formed microcracks due to drilling respectively preparational works, in microcapillary tubes of anhydrite crystals and rarely in micro-porous parts of the Hauptsalz.

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