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Tripelelement-Stabilisotopensignaturen zur Untersuchung des atmosphärischen Chlormethanbudgets

Die stratosphärische Ozonschicht absorbiert die UV-C und UV-B Sonnenstrahlung und schützt damit Pflanzen, Tiere und Menschen vor Strahlenschäden. Durch anthropogen emittierte Fluorchlorkohlenwasserstoffe (FCKWs) wird die Ozonschicht abgebaut. Da FCKWs seit dem Montrealer Protokoll stark zurückgegangen sind, werden halogenierte Verbindungen wie Chlormethan (CH3Cl), die aus natürlichen Quellen freigesetzt werden, für den Abbau der Ozonschicht in der Stratosphäre zunehmend relevant. CH3Cl ist das am häufigsten vorkommende chlorhaltige Spurengas in der Erdatmosphäre, das für etwa 17% der durch Chlor katalysierten Ozonzerstörung in der Stratosphäre verantwortlich ist. Daher wird CH3Cl vornehmlich die zukünftigen Gehalte an stratosphärischem Chlor bestimmen. Die aktuellen Schätzungen des globalen CH3Cl-Budgets und die Verteilung der Quellen und Senken sind sehr unsicher. Ein besseres Verständnis des atmosphärischen CH3Cl-Budgets ist daher das Hauptziel dieses Projektes.Die Analyse stabiler Isotopenverhältnisse von Wasserstoff (H), Kohlenstoff (C) und Chlor (Cl) hat sich zu einem wichtigen Werkzeug zur Untersuchung des atmosphärischen CH3Cl-Budgets entwickelt. Das zugrundeliegende Konzept besteht darin, dass das atmosphärische Isotopenverhältnis einer Verbindung wie CH3Cl gleich der Summe der Isotopenflüsse aus allen Quellen angesehen werden kann, korrigiert um den gewichteten durchschnittlichen kinetischen Isotopeneffekt aller Abbauprozesse. Dadurch ist es möglich, die Bedeutung wichtiger Quellen und Senken mit bekannten Isotopensignaturen zu entschlüsseln. Eine Grundvoraussetzung für detaillierte Hochrechnungen des globalen Budgets ist die Bestimmung der durchschnittlichen Isotopenverhältnisse von H, C und Cl des troposphärischen CH3Cl. Aufgrund der relativ geringen Konzentration von atmosphärischem CH3Cl von ~550 ppbv stellt dies eine große messtechnische Herausforderung dar. Daher liegt der Schwerpunkt dieses Antrags auf der erfolgreichen Entwicklung von Dreifachelement-Isotopenmethoden zur genauen Messung von atmosphärischem CH3Cl.Im ersten Schritt wird ein Probenahmesystem für große Luftmengen konstruiert und für die Messungen der stabilen Isotopenverhältnisse von CH3Cl optimiert. Das Probenahmegerät wird zunächst im Labor getestet und dann zum Sammeln von Luftproben an drei verschiedenen Orten eingesetzt: an der Universität Heidelberg, am Hohenpeißenberg und im Schneefernerhaus. Die Probenahmen werden über einen Zeitraum von einem Jahr durchgeführt, um möglichst auch saisonale Schwankungen zu erfassen. Die Isotopenverhältnisse der Proben werden mit modernsten massenspektrometrischen Methoden im Labor gemessen. Die Ergebnisse aller Standorte und Zeitpunkte werden in der Gesamtheit evaluiert, um die durchschnittlichen stabilen H-, C und Cl-Isotopenwerte einschließlich ihrer saisonalen Schwankungen darzustellen. Abschließend werden die Daten hinsichtlich ihrer Anwendbarkeit für komplexe numerische Modelle kritisch diskutiert.

CO2 degassing from karstic springs in Southern Germany

This study examines characteristics of dissolved inorganic carbon (DIC) and partial pressures of CO2 characteristics (pCO2) in the source springs and headwaters of four karstic watersheds, via dissolved inorganic carbon concentration and stable carbon isotope measurements. All four spring sources are located in Southern Germany and were measured for water chemistry and stable isotopes with nearby headwater stream points, which were located up to 100 m downstream of the discharge points. Seasonal sampling covered winter, spring, summer, and autumn in 2018.

Alkane abundance and stable isotope measurements from ELSA stack lake sediments, Eifel Volcanic Field, Germany

n-alkane peak areas from GC-FID measurements. Compound specific hydrogen and carbon isotope measurements made using GC-IRMS. Samples taken from Auel Maar, Holzmaar, and Schalkenmehrener maar lake sediment cores spanning 60,000 years. Age model information and additional proxy data from the ELSA-20 stack are found in Sirocko et al., 2021 (Nature Geoscience) and Sirocko et al., 2022 (Scientific Reports). Full methodological details are found in Zander et al., 2025 (Rapid Communications in Mass Spectrometry).

Pore-water DIC and δ13C-DIC data, as well as solid-phase porosity and TOC data from a MUC core from RV HEINCKE cruise HE595 at Tonne E3 in the Helgoland Mud Area, SE German Bight

This dataset includes downcore measurements of dissolved inorganic carbon (DIC) and its stable carbon isotopic composition (δ13C-DIC), as well as solid-phase porosities and total organic carbon (TOC) contents from a sediment core retrieved using multi-corer sampling during RV Heincke expedition HE595 in 2022. The samples were collected in the framework of the Project APOC (Anthropogenic impacts on particulate organic carbon cycling in the North Sea). DIC contents were determined in the laboratories of the Alfred Wegener Institute (AWI) in Bremerhaven, Germany. The δ13C-DIC data were produced at MARUM—Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany. Solid-phase porosity data were produced in the laboratories of the Alfred Wegener Institute (AWI) in Bremerhaven, Germany. Total organic carbon contents were determined at the Faculty of Geosciences at the University of Bremen, Bremen, Germany.

Datenarchiv Sondermessungen in Mecklenburg-Vorpommern

Zur Erfassung der Luftqualität in Mecklenburg-Vorpommern werden an ausgewählten Standorten Sondermessprogramme durchgeführt. U.a. handelt es sich um Sondermessprogramme zur Ermittlung der Immissionsbelastung im Rostocker Stadtgebiet, zur Beurteilung der Verkehrsimmissionen an verschiedenen Standorten in M-V, zur Ermittlung von Ammoniakimmissionen und Nährstoffeinträgen in der Nähe von Tierhaltungsanlagen und zur Ermittlung der Feinstaubimmissionen (zeitliche Entwicklung und Ursachen) in M-V. Der Datenbestand setzt sich aus kontinuierlichen und diskontinuierlich gewonnenen Messdaten der Hauptluftschadstoffe - Schwebstaub, Feinstaub (PM10), Schwefeldioxid, Kohlenmonoxid, Stickstoffmonoxid, Stickstoffdioxid, Ozon, Benzol, Toluol, Ruß und Ammoniak zusammen. Dabei handelt es sich um Messdaten, die aus zusätzlich durchgeführten Messprogrammen gewonnen wurden. U.a. wurden Messdaten mit einem Messwagen an verschiedenen Standorten in M-V ermittelt. An verschiedenen ländlichen Standorten wird die NH3-Konzentration bestimmt. Es werden Messprogramme zur Ermittlung der Verkehrsimmissionen an verschiedenen Standorten in M-V durchgeführt (u.a. zur Ermittlung sogenannter "hot spots").

Impact of long-term exposure to elevated pCO2 on activity and populations of free living N2 fixing organisms in a temperate grassland system

The project aims at achieving a better understanding of the processes that drive or limit the response of grassland systems in a world of increasing atmospheric pCO2. We will test the hypothesis that the previously shown increase in below-ground allocation of C under elevated pCO2 provides the necessary energy excess and will stimulate free-living N2 fixers in a low N grassland environment. The project thus aims at assessing the occurrence and importance of free-living N2 fixers under elevated pCO2 and identify the associated microbial communities involved in order to better understand ecosystems response and sustainability of grassland systems. This project had the last opportunity to obtain soil samples from a grassland ecosystem adapted to long-term (10 year) elevated atmospheric pCO2 as the Swiss FACE experiment. The project aims to identify the relevant components of free-living diazotrophs of the microbial community using 15N stable isotope - DNA probing.

Linking internal pattern dynamics and integral responses - Identification of dominant controls with a strategic sampling design

In hydrology, the relationship between water storage and flow is still fundamental in characterizing and modeling hydrological systems. However, this simplification neglects important aspects of the variability of the hydrological system, such as stable or instable states, tipping points, connectivity, etc. and influences the predictability of hydrological systems, both for extreme events as well as long-term changes. We still lack appropriate data to develop theory linking internal pattern dynamics and integral responses and therefore to identify functionally similar hydrological areas and link this to structural features. We plan to investigate the similarities and differences of the dynamic patterns of state variables and the integral response in replicas of distinct landscape units. A strategic and systematic monitoring network is planned in this project, which contributes the essential dynamic datasets to the research group to characterize EFUs and DFUs and thus significantly improving the usual approach of subdividing the landscape into static entities such as the traditional HRUs. The planned monitoring network is unique and highly innovative in its linkage of surface and subsurface observations and its spatial and temporal resolution and the centerpiece of CAOS.

Barley compatibility factors pivotal for root colonisation and manipulation of basal defence by Piriformospora indica

This project is aimed at the characterization of the systemic reprogramming in barley, which modulates the compatible interaction with the biotrophic leaf pathogen Blumeria graminis f.sp. hordei upon root infestation with the mutualistic endophyte Piriformospora indica. We have recently shown that the basidiomycete P. indica - upon successful establishment in the roots - reprograms barley to salt stress tolerance, resistance to root diseases and higher yield (Waller et al., 2005). Successful powdery mildew infections in barley leaves are also disturbed by the mutualistic fungus. These processes are associated with a strong change in plant metabolism, especially with a drastic alteration of leaf and root antioxidants. On the basis of these findings we will perform an in-depth analysis of the barley metabolome (B6) and transcriptome (B7) with two specific foci: First, to elucidate the process of establishment of the mutualistic fungus within the barley roots; second, to characterize elements of the systemic response in leaves leading to an interruption or failure of compatibility processes required for successful establishment of biotrophic leaf pathogens like Blumeria. New gene candidates will be pre-selected systematically for their regulatory role in compatibility by means of transiently transformed barley leaves upon Blumeria inoculation. Stable transgenic barley and maize lines (B3) generated with verified gene candidates and genes identified by other projects (A1, A2, B5, B6) will be tested with Blumeria and P. indica. By comparing candidate genes in the different plant - microbe systems, we will identify common regulatory processes, metabolites and metabolic networks implicated in compatibility including those required for successful interactions with mutualistic fungi.

RUBIN - PhoTech - VP3 biogene & industrielle Luft, TP3.2: Photonischer Abbau biogener und industrieller Schadstoffe mittels Photokatalyse

NECPR: Additional Reporting Obligations in the area of Energy Efficiency (Annex XVII) dataset

Additional reporting obligations in the area of energy efficiency' is a dataset reported by EU Member States and Contracting Parties of the Energy Community under the Governance Regulation. The dataset includes information on reasons why energy consumption is stable or growing per sector, floor area of government buildings not meeting energy performance requirements, number of energy audits carried out in large companies, applied national primary energy factor for electricity, number and floor area of new and renovated nearly zero-energy buildings (NZEB), and internet links to lists/interfaces of energy services.

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