API src

Found 425 results.

Absolute abundances of methane- and sulfate-cycling microorganisms, pore water gas concentrations and stable carbon isotopes (Table 1)

Soil cores for microbial, dissolved gas concentrations and isotopic analysis were taken using a Russian type peat corer (De Vleeschouwer et al. 2010) before and after rewetting. Each time, we took duplicates at stations 1-8 for this rather labor-intensive process and divided the core into four depth sections: surface, 5–20, 20–40 and 40–50 cm. Subsamples for dissolved gases and stable carbon isotope analyses were taken with tip-cut syringes with a distinct volume of 3 ml (Omnifix, Braun, Bad Arolsen, Germany) and immediately placed into NaCl-saturated vials (20 ml, Agilent Technologies, 5182-0837, Santa Clara, USA) leaving no headspace and closed gas-tight using rubber stoppers and metal crimpers (both: diameter 20 mm, Glasgerätebau Ochs, Bovenden, Germany).

Dissolved methane concentrations of water samples from the North Sea during ALKOR cruise AL575 (27 June 2022 - 13 July 2022)

Water sampling was conducted during AL575 cruise in the North Sea by using Niskin Bottles attached to CTD/Water sampler rosette and ROV (Haeckel and Schmidt, 2024). To detect methane anomalies in the water column derived from seafloor gas emissions the recovered water samples were processed by using headspace gas sampling and subsequent gas chromatographic analysis. Based on measured methane concentrations of headspace gas in (micro-atm) the dissolved methane concentrations in water were calculated (nmol l-1).

Hydrogeochemical dataset for characterization of the deep Aalenian Sandstone aquifer (Middle Jurassic) in Potsdam, Germany

This dataset is part of a research collaboration between Energie und Wasser Potsdam (EWP) and the GFZ Helmholtz Centre for Geosciences. The main objective of this research collaboration was to evaluate the suitability of the subsurface in the Potsdam area for deep geothermal energy. EWP is currently constructing a geothermal power plant using the aquifer of the here exploited Jurassic sandstones. From December 2022 to May 2023, two deep wells were drilled in the center of the city Potsdam, Germany, targeting the Jurassic Aalenian Sandstone at depths between 983 and 1180 m below surface. Hydraulic tests were performed immediately after completion of each well. More than 15,000 m3 of formation water was produced. Geochemical analysis were performed on the produced formation water with the objective of characterizing the fluid properties in terms of geothermal usage, e.g. corrosion and scaling potential. The results of the analysis of physicochemical on-site monitoring and performed on-site tests, inorganics, organics, gas composition, heat capacity and naturally occurring radioactive materials are presented in this data publication.

Brackish water rewetting of a temperate coastal peatland in NE Germany: Effects on Biogeochemistry, Microorganisms and Greenhouse gas emissions

The rewetting of drained peatlands is a promising measure to mitigate carbon dioxide (CO2) emissions by preventing the further mineralization of the peat soil through aeration. While freshwater rewetted peatlands can be significant methane (CH4) sources in the short-term, in coastal ecosystems the input of sulfate-rich seawater could potentially mitigate these emissions. The purpose of the data collection was to examine whether the presence of sulfate, known as an alternative electron acceptor, can cause lower CH4 production and thus, emissions by favoring the growth of sulfate-reducers, which outcompete methanogens for substrate. We therefore investigated underlying variables such as the methane-cycling microbial community along with CH4 fluxes and set them in context with CO2 fluxes along a transect in a coastal peatland before and directly after rewetting. In this way, a conclusion about the short-term greenhouse gas mitigation potential of brackish water rewetting of coastal peatlands could be drawn. This data collection consists of six data sets, with direct comparisons before and after rewetting of CO2 and CH4 fluxes (Tab. 2) and associated microbial communities (Tab. 1) being the main data. Pore water geochemistry (Tab. 1 and 3) and surface water parameters (Tab. 4) were collected simultaneously to provide potential explanatory variables. The sampling of continuous water level (Tab. 5) within wells and atmospheric weather data (air and soil temperature, relative humidity, photosynthetic photon flux density; Tab. 6) from a weather station was done in addition. Measurements started in June/July/August 2019 after field installation was finalized and were conducted on the drained coastal fen "Polder Drammendorf" on the island of Rügen in North-East Germany. On 26th November 2019, the dike was opened and channeled in order to rewet the peatland with brackish water. Before, the dike separated the peatland from the adjacent bay "Kubitzer Bodden", which is part of a brackish lagoon system connected to the Baltic Sea. Therefore, the peatland was nearly completely flooded and now resembles a shallow lagoon with high fluctuating water levels. We measured along a humidity (pre-rewetting)/water level (post-rewetting) gradient (stations 0-8) towards and across the main North-South oriented drainage ditch, including four stations on the Eastern side of the ditch (1–4), two ditch stations (0, 5) and two stations (6, 7) on the Western side of the ditch. Station 8 was chosen as an additional station farther towards the adjacent bay on the Western side, but was only accessible before rewetting. CH4 and CO2 fluxes (stations 0-7) were calculated from online gas concentrations measurements using laser-based analyzers and manual closed chambers (Livingston, G. P., & Hutchinson, G. (1995). Enclosure-based measurement of trace gas exchange: Applications and sources of error. In P.A. Matson, & R.C. Harriss (Eds.). Biogenic trace gases: Measuring emissions from soil and water (pp. 14–51). Blackwell Science Ltd., Oxford, UK). Soil cores for microbial, dissolved gas concentrations and isotopic analysis were taken using a Russian type peat corer (De Vleeschouwer, F., Chambers, F. M., & Swindles, G. T. (2010). Coring and sub-sampling of peatlands for palaeoenvironmental research. Mires and Peat, 7, 1–10) before and after rewetting. Each time, we took duplicates at stations 1-8 for this rather labor-intensive process and divided the core into four depth sections: surface, 5–20, 20–40 and 40–50 cm. Subsamples for dissolved gases and stable carbon isotope analyses were taken with tip-cut syringes with a distinct volume of 3 ml (Omnifix, Braun, Bad Arolsen, Germany) and immediately placed into NaCl-saturated vials (20 ml, Agilent Technologies, 5182-0837, Santa Clara, USA) leaving no headspace and closed gas-tight using rubber stoppers and metal crimpers (both: diameter 20 mm, Glasgerätebau Ochs, Bovenden, Germany). Absolute abundances of specific functional target genes, including methane- and sulfate-cycling microorganisms, were measured with quantitative PCR (qPCR) after DNA was extracted (GeneMATRIX Soil DNA Purification Kit, Roboklon, Berlin, Germany) and quantified (Qubit 2.0 Fluorometer, ThermoFisher Scientific, Darmstadt, Germany). Surface and pore water parameters were measured in parallel to the gas measurements and soil coring for microbial analyses. Most surface water variables (pH, specific conductivity, salinity, nutrients, oxygen, sulfate and chloride concentrations, DOC/DIC) were measured in-situ using a multiparameter digital water quality meter or taken to the laboratory as water samples for further analysis. Likewise, pore water/soil variables (pH, specific conductivity, nutrients, metals, sulfate and chloride concentrations, CNS) were either measured in-situ or taken to the laboratory as soil samples. While surface water analysis was only conducted in the drainage ditch before rewetting, it was done along the entire transect after rewetting. In contrast, pore water/soil analysis was mostly conducted before rewetting and only repeated occasionally after rewetting where possible.

Die oberflaechliche Kontamination von Koernerfruechten bei direkter Trocknung mit Propangas und Heizoel EL (Fe, Mn, Cu, Zn, Mo, Cr, Ni, Se, Cd, Pb, As, Hg, S, F, NO2, NO3)

Nachweis aller im Rauchgas/Luftgemisch von Fluessiggas- und Leichtoelbrennern auftretenden Stoffe (Pb, F, CrIII, CrVI, Zn, Se, Ni, As, Hg, Cd, Mo, Sn, Cu, SO2, Hf, NOx, polycyklische Aromate) bei Variation von Luftmenge, Gas- bzw. Oelmenge und Brennereinstellung. Ermittlung der Ablagerungen aus diesem Rauchgas/Luftgemisch auf Koernerschuettungen in Satz- und Durchlauftrocknern.

Untersuchungen und Bewertung der Porenluft der Deponie Aach hinsichtlich moeglicher Gefaehrdungen bei Sanierungsarbeiten

Konzeptionen der Schadstoffmessung, einschliesslich Laerm und Strahlen

Sonderforschungsbereich (SFB) 990: Ökologische und sozioökonomische Funktionen tropischer Tieflandregenwald-Transformationssysteme (Sumatra, Indonesien), Teilprojekt A05: Fachliche Zuordnung Bodenwissenschaften Förderung Förderung seit 2012

Unser Projekt hat folgende Ziele: 1. Die Bewertung von Managementsystemen von Palmöl-Plantagen im Hinblick auf die N2-Fixierung und die Effizienz mit der Nährstoffe genutzt und im System gespeichert werden. 2. Ableitung einer Treibhausgasbilanz auf Ökosystemebene durch die Kombination von Gasflussmessungen im Boden mit Messungen der Eddy-Kovarianz. 3. Die Bestimmung des Anteils von Nitrifikation und Denitrifikation an den N2O-Flüssen und die Quantifizierung der räumlichen und zeitlichen Variabilität von Treibhausgasflüssen im Boden. 4. Die Bewertung des Beitrags von Flussufer- und -Auenbereichen sowie Baumstammemissionen zur Treibhausgasbilanz auf Landschaftsebene.

Durchfuehrung und Bewertung von Gasanalysen an der Zentraldeponie Mertesdorf

Konzeptionen der Schadstoffmessung, einschliesslich Laerm und Strahlen

Messsysteme für Großerzeugungs-Anlage, Teilvorhaben: Aufbau und Überprüfung einer Stresstest-Methodik zur Analyse und Absicherung von Sicherheits- und Robustheitseigenschaften

Zur Erreichung der gesteckten Klimaziele werden bis 2030 erneuerbare Erzeugungsmengen von mehr als 300 TWh benötigt. Über intelligente Messsysteme können entsprechende Erzeugungsanlagen sicher informationstechnisch angebunden und für die Netzintegration und Vermarktung gesteuert werden - was bislang jedoch nur für kleine Anlagen möglich ist. Im Rahmen des Projekts MeGA wird unter Nutzung des Sicherheitskonzepts des Smart Meter Gateways (SMGW) ein entsprechendes Konzept für die Anbindung von Großerzeugungsanlagen (GA) entwickelt und bis zum Feldtest gebracht, woraus sich ein neuer Anwendungsbereich der SMGW-Technologie erschließt. Ein Schwerpunkt der Arbeiten der Hochschule Albstadt-Sigmaringen bildet der Aufbau von Konzepten zur Analyse und Absicherung einer sicheren Steuerung von GAs auf Grundlage der SMGW-Infrastruktur, berücksichtigend verschiedene Aspekte der IT-Sicherheit und der Robustheit von IT-Systemen, wie etwa Angriffsszenarien, Fehlertoleranzverhalten, Ausfallsicherheit. Dies beinhaltet die Erarbeitung und Konsolidierung von Sicherheitsanforderungen bei der Steuerung von GAs, daraus abgeleitet die Erstellung eines Konzepts zur Analyse relevanter Sicherheits- und Robustheitseigenschaften, sowie dessen Umsetzung innerhalb einer entsprechenden Analyseumgebung. Darauf aufsetzend erfolgt der Aufbau einer Stresstest-Methodik zur systematischen Analyse und Absicherung von Sicherheits- und Robustheitseigenschaften, deren Anwendung die Labor- und Feldtestphase des Projekts aktiv begleitet. Weitere Arbeiten der Hochschule Albstadt-Sigmaringen adressieren im Rahmen der Anforderungsanalyse die Identifikation und Klassifikation energiewirtschaftlicher Marktrollen und relevanter Anwendungsfälle, sowie deren Abbildung in ein Rollen- und Kommunikationsmodell, welches die Grundlage für eine systematische Analyse der spezifischen Leistungsanforderungen an die WAN-Kommunikation von GAs liefert.

Analyse der innermotorischen Emissionsentstehung und Wirkmechanismen potentieller Abgasnachbehandlungskonzepte, Teilvorhaben: Analyse der innermotorischen Emissionsentstehung und potentieller Abgasnachbehandlungskonzepte

1 2 3 4 5 … 41 42 43