Refine
Year of publication
Document Type
- Doctoral Thesis (82)
- Article (62)
- Final Thesis (1)
Has Fulltext
- yes (145)
Is part of the Bibliography
- no (145)
Keywords
- - (25)
- Biosphärenreservat (8)
- Vietnam (7)
- Ostsee (6)
- Deutschland (5)
- Geochemie (5)
- Tourismus (5)
- Fernerkundung (4)
- Germany (4)
- Nachhaltige Entwicklung (4)
- Nachhaltigkeit (4)
- Naturschutz (4)
- behavior change (4)
- bentonite (4)
- climate change (4)
- protected areas (4)
- Biosphärenreservate (3)
- Geopolymer (3)
- Großschutzgebiet (3)
- Holozän (3)
- Klimawandel (3)
- Pleistozän (3)
- Remote Sensing (3)
- Wirtschaftsgeographie (3)
- biosphere reserves (3)
- moral disengagement (3)
- smectite (3)
- Adaptation (2)
- Agri-food networks (2)
- Bach Ma Nationalpark (2)
- Bioökonomie (2)
- Circular economy (2)
- Daseinsvorsorge (2)
- Deutschland <DDR> (2)
- Eiszeit (2)
- Empirische Sozialforschung (2)
- Geografie (2)
- Geophysik (2)
- Geostatistics (2)
- Grand Societal Challenges (2)
- Habitat (2)
- Hydroakustik (2)
- Jura (2)
- Kommunalfinanzen (2)
- Landsat (2)
- Mecklenburg-Vorpommern (2)
- Meeresboden (2)
- Mikromorphologie (2)
- Mobilität (2)
- Monitoring (2)
- Nordostdeutschland (2)
- Nordsee (2)
- Partizipation (2)
- Peripherie (2)
- Politik (2)
- Reactive transport (2)
- Regionalentwicklung (2)
- Russland (2)
- Röntgendiffraktometrie (2)
- SEM–EDS (2)
- Südafrika (2)
- Tourism (2)
- Transformation (2)
- UNESCO (2)
- Vulnerability (2)
- case study (2)
- ecosystem services (2)
- emotions (2)
- high-carbon behavior (2)
- lake sediments (2)
- lake-level changes (2)
- layer charge (2)
- metal substitution (2)
- moral motivation (2)
- organic supplements (2)
- palynology (2)
- pro-environmental behavior (2)
- soil erosion (2)
- sustainable development (2)
- tourism (2)
- Ökosystemdienstleistung (2)
- (moral) emotions (1)
- ABM test (1)
- AHP (1)
- AMSWOT-Analyse (1)
- Abflussmenge (1)
- Acoustic Backscatter (1)
- Actinopterygii (1)
- Actor-based typology (1)
- Adaption (1)
- Agenda 21 (1)
- Agenda-Setting (1)
- Agri-Food Networks (1)
- Agricultural crop (1)
- Akteurzentrierter Institutionalismus (1)
- Akzeptanz (1)
- Alkali-activated binder (1)
- Alkaliaktivierung (1)
- Alluvialebene (1)
- Altindustrieregion (1)
- Alumino-silicate glass (1)
- Analyse (1)
- Anatomie (1)
- Animal husbandry (1)
- Anpassung (1)
- Anthropogene Klimaänderung (1)
- Anthropogener Einfluss (1)
- Applying GIS and Remote sensing (1)
- Aquatisches Sediment (1)
- Assemblage (1)
- Austria (1)
- Auswas (1)
- Authigenic carbonates (1)
- Bach Ma National Park (1)
- Backpacking (1)
- Balanced cross sections (1)
- Balkan (1)
- Baltic Sea (1)
- Bayerischer Wald (1)
- Beach ridge (1)
- Benachteiligte Bevölkerungsgruppen (1)
- Benchmark material (1)
- Benthic macrofauna (1)
- Benthos (1)
- Bergmann’s rule (1)
- Bevölkerung (1)
- Big Data (1)
- Biodiesel (1)
- Biophysical Parameters (1)
- Bioturbation (1)
- Bodenerosion (1)
- Business models (1)
- Bürgermeister (1)
- COVID-19 (1)
- Caledonian Deformation Front (1)
- Carbon isotopes (1)
- Carbonate microfacies (1)
- Carboniferous sequence (1)
- Caribbean region (1)
- Cayman Trog (1)
- Central Asia (1)
- Changai (1)
- Change agents (1)
- China (1)
- Choice Experiment (1)
- Chondrichthyes (1)
- Clay mineral diagenesis (1)
- Climate Change (1)
- Climate change (1)
- Cluster Analysis (1)
- Cluster analysis (1)
- Coal mining (1)
- Cochrane–Orcutt procedure (1)
- Computational fluid dynamic simulations (1)
- Coniopterygidae (1)
- Contamination (1)
- Crete (1)
- Cuba (1)
- Cyprus (1)
- Cäsium-137 (1)
- DDT (1)
- Dark Ages Cold Period (DACP) (1)
- Darss-Zingst-Hiddensee (1)
- Deep geological repository (1)
- Dehydroxylierung (1)
- Demographie (1)
- Diagenese (1)
- Diatomeen (1)
- Dietary behavior (1)
- Digitalisation (1)
- Digitalisierung (1)
- Dinosauria (1)
- Dinosaurier (1)
- Diskurs (1)
- Diskursanalyse (1)
- Diskursive Repräsentation (1)
- Distribution (1)
- Durchbruchstal (1)
- Durchführbarkeit (1)
- Düne (1)
- ERS (1)
- EU Water Framework Directive (1)
- Early Jurassic (1)
- Ecological niche modelling (1)
- Economics (1)
- Ecuador (1)
- Eem-Interglazial (1)
- Eemian (1)
- Einflussgröße (1)
- Einzelhandel (1)
- Eisenmineralien (1)
- Eisflussmodellierung (1)
- Elektromobilität (1)
- Endlagerforschung (1)
- Endmoräne (1)
- Entstehung (1)
- Entwicklung (1)
- Environmental factors (1)
- Erfolgsfaktor (1)
- Erholung (1)
- Ernährungsgewohnheiten (1)
- Ernährungsökologie (1)
- Eutrophication (1)
- Evaluierung (1)
- Evapotranspiration (1)
- Evolutionäre Wirtschaftsgeographie (1)
- Experiment (1)
- Fault-related folding (1)
- Fazies (1)
- Faziesanalyse (1)
- Fertilität (1)
- Finanzausgleich (1)
- Fische (1)
- Fischland-Darß-Zingst (1)
- Fiskalföderalismus (1)
- Flachmeer (1)
- Fleischkonsum (1)
- Fließgewässer (1)
- Focused ion beam polishing (1)
- Food labeling (1)
- Food policy (1)
- Food waste (1)
- Foraminiferen (1)
- Forest dieback (1)
- Fourier analysis (1)
- Framing (1)
- Freistaat Bayern (1)
- Friedland clay (1)
- Friedland tons (1)
- Friedlandton (1)
- Fächerecholot (1)
- Fähigkeitenansatz (1)
- Föderaler Okrug Sibirien (1)
- Förderbrunnen (1)
- GIS (1)
- Gegenwart (1)
- Gemeinde (1)
- Gemeindeentwicklung (1)
- Gemeinden (1)
- Generelle-Interessen-Skala (1)
- Genese (1)
- Geochemistry (1)
- Geochronologie (1)
- Geodynamik (1)
- Geographies of Waste (1)
- Geographies of waste (1)
- Geoinformatik (1)
- Geoinformationssystem (1)
- Geologie (1)
- Geomorphologie (1)
- Geostatistik (1)
- Germany <GDR> (1)
- Geschichte (1)
- Gesellschaft für Industrieservice AG (1)
- Gesteinskunde (1)
- Gewässer (1)
- Glacial gastropod faunas of Central Europe recent in Central Asia (1)
- Glaciation (1)
- Glacitectonics (1)
- Glazitektonik (1)
- Global South regional policy (1)
- Governance (1)
- Gravettian (1)
- Great Caribbean Arc (1)
- Grimmen (1)
- Groundwater monitoring (1)
- Grubenwasser (1)
- Grundwasser (1)
- Grönland (1)
- HCH (1)
- HLRW (1)
- HLW- Endlager (1)
- HLW- repository (1)
- Halbinsel Kola (1)
- Hanoi (1)
- Heimat (1)
- Herkunft (1)
- Hiddensee (1)
- Highly porous structure (1)
- Hindernis (1)
- Hispaniola (1)
- Hochschulschrift (1)
- Holocene (1)
- Holocene climate change (1)
- Horizon 2020 (1)
- Hue (1)
- Hybodontiformes (1)
- Hydrochemistry (1)
- Hydrogeologie (1)
- Hydrogeology (1)
- Ibbenbüren (1)
- Ibbenbüren anthracite coal mine (1)
- Illit (1)
- Illit/Smektit (1)
- Illite morphology (1)
- In-situ Measurements (1)
- In-situ-Messungen (1)
- Indicator Kriging (1)
- Indikator-Kriging (1)
- Individualtourismus (1)
- Indonesia (1)
- Indonesien (1)
- Information (1)
- Infrastruktur (1)
- Inklusive Politik (1)
- Innovation (1)
- Innovationpolitik (1)
- Innovationspolitik (1)
- Institutional Analysis (1)
- Institutionalisierung (1)
- Interstadial (1)
- Isotop (1)
- Ispra / Space Applications I (1)
- Ispra / Space Applications Institute (1)
- Jakosbweg (1)
- Jamaika (1)
- Jasmund (1)
- Jurassic (1)
- Kaledoniden (1)
- Kaltzeitliche Gastropoden-Faunen Mitteleuropas rezent in Zenrtralasien (1)
- Kaolinite melting (1)
- Karbonat (1)
- Karbonatsystem (1)
- Karibik (1)
- Karibik <Nordwest> (1)
- Karibische Flutbasaltprovinz (1)
- Karte (1)
- Kartografie (1)
- Kartographiegeschichte (1)
- Kemerovo Oblast (1)
- Kemerowo (1)
- Kimmeridgian (1)
- Klima (1)
- Klimaanpassung (1)
- Klimaänderung (1)
- Kluster-Kriging (1)
- Kohle (1)
- Kohlenbergwerk (1)
- Komponentenanalyse (1)
- Kosten (1)
- Kreislaufwirtschaft (1)
- Kriging (1)
- Krise (1)
- Kristallstruktur (1)
- Kuba (1)
- Kulturtourismus (1)
- Küstenentwicklung (1)
- Lackporlinge (1)
- Lake-level variation (1)
- Lakes (1)
- Lakustrisches Sediment (1)
- Land cover change (1)
- Land mapping unit (1)
- Land potential productivity assessment (1)
- Land suitability evaluation (1)
- Landbedeckungsänderung (1)
- Landeignungsbewertung (1)
- Lander Experiment (1)
- Landformanalyse (1)
- Landkartierungseinheit (1)
- Landnutzung (1)
- Landpotenzialproduktivität (1)
- Landsat Time series analysis (1)
- Landscape Metrics (1)
- Landscape Monitoring (1)
- Landscape development (1)
- Landschaftsentwicklung (1)
- Landschaftsmonitoring (1)
- Landschaftsstruktur (1)
- Landschaftsstrukturanalyse (1)
- Landschaftsästhetik (1)
- Landslide hazard assessment (1)
- Landwirtschaft (1)
- Laser Line Scanning (1)
- Late Jurassic (1)
- Late Pleistocene (1)
- Late-Holocene (1)
- Lausitzer Braunkohlerevier (1)
- Lebensmittel (1)
- Lexikometrie (1)
- LiDAR (1)
- Life Cycle Assessment (1)
- Lithofazies (1)
- Lithologie (1)
- Logistische Regression (1)
- Lower Saxony (1)
- Lower Toarcian (1)
- Lumineszenz-Datierung (1)
- Luxustourismus (1)
- Ländlicher Raum (1)
- Lösungskinetik (1)
- MAB (1)
- MX80-bentonit (1)
- MX80-bentonite (1)
- Madagascar (1)
- Madagaskar (1)
- Malaria (1)
- Management (1)
- Mangan (1)
- Map (1)
- Marine Habitat Mapping (1)
- Marine Habitatkartierung (1)
- Marokko (1)
- Mecklenburg (1)
- Medieval Climate Anomaly (MCA) (1)
- Mediterranean (1)
- Meeresspiegelschwankung (1)
- Mergers and Acquisitions (1)
- Metakaolin (1)
- Mexico (1)
- Mexiko (1)
- Micromorphology (1)
- Migration (1)
- Mikrostruktur (1)
- Mikrostrukturelle Analyse (1)
- Milos (1)
- Mine drainage (1)
- Mitteldevon (1)
- Mitteleuropa (1)
- Mittlere Elbe (1)
- Modellbildung (1)
- Modellierung (1)
- Modernisierung (1)
- Modernization (1)
- Molybdän (1)
- Mongolei (1)
- Mongolia (1)
- Mongolischer Altai (1)
- Morocco (1)
- Mortalität (1)
- Multi-channel shop (1)
- Multi-level perspective (1)
- Multibeam Echosounder (1)
- Multimodel inference (1)
- Multinationales Unternehmen (1)
- Murmansk (1)
- Muschelkrebse (1)
- NGO (1)
- NUTS2-Regionen (1)
- Nachhaltige Ernährung (1)
- Nachhaltige Ressourcennutzung (1)
- Nachrichtenanalyse (1)
- Nam Dinh Gebiet (1)
- Nam Dinh area (1)
- Nationalpark (1)
- Nationalpark Gesäuse (1)
- Nationalpark Hohe Tauern (1)
- Naturschutzbegründung (1)
- Naturschutzgebiete (1)
- Nehrung (1)
- Neotropics (1)
- Netzwerk (1)
- New Zealand coals (1)
- New social commerce (1)
- Nichtregierungsorganisation (1)
- Niedersachsen (1)
- Nitrate (1)
- Nord Jasmund Fault (1)
- Nordatlantik-Oszillation (1)
- Nordsee <Süd> (1)
- North Atlantic Oscillation (1)
- Northeast German Plain (1)
- Numerical modelling (1)
- Nutzwälder (1)
- OSL (1)
- Oberflächendatierung (1)
- Oblast Murmansk (1)
- Oblast’ Kemerovo (1)
- Old Red (1)
- Old industrial region (1)
- Online marketplace (1)
- Online-Marktplatz (1)
- Optische Fernerkundung (1)
- Oriente (1)
- Ostracodes (1)
- Ostseeküste (Südwest) (1)
- Ostseeraum (1)
- Oxygen isotopes (1)
- Ozeanversauerung (1)
- POSL (1)
- PRISMA (1)
- Paleoclimate (1)
- Paläoklima (1)
- Paläontologie (1)
- Paläoozeanographie (1)
- Participation (1)
- Peatland species mapping (1)
- Perception (1)
- Petrobaltic (1)
- Phragmites (1)
- Pilgern (1)
- Pilgrimage (1)
- Plasma spraying (1)
- Plattentektonik (1)
- Pleistocene (1)
- Pleistocene Europe (1)
- Pleistozän-Holozän-Grenze (1)
- Poland (1)
- Polen (1)
- Pollution (1)
- Pommersche Haupteisrandlage (1)
- Population dynamics (1)
- Pore-size distributions (1)
- Portable OSL (1)
- Potato industry (1)
- Principle Component Analysis (1)
- Process (1)
- Profilbilanzierung (1)
- Protected Area Management (1)
- Protokaribik (1)
- Präferenz (1)
- Präferenzanalyse (1)
- Public parks (1)
- Pufferzone (1)
- Pumpe (1)
- Pumptests (1)
- Pupilla loessica (1)
- Pyrite (1)
- Qualitative Empirsiche Sozialforschung (1)
- Qualitative research (1)
- Quantitative emprische Sozialforschung (1)
- Quecksilber (1)
- Radiographie (1)
- RapidEye (1)
- Rapsanbau (1)
- Rauigkeit <Akustik> (1)
- Raumordnung (1)
- Reactive thin films (1)
- Regional Disparitäten (1)
- Regionale Geographie (1)
- Regionale Identität (1)
- Regionale Pfadentwicklung (1)
- Reisekostenmodell (1)
- Rektorit (1)
- Remote sensing (1)
- Repository research (1)
- Reptilien (1)
- Reservoir modelling (1)
- Residualbevölkerung (1)
- Residues (1)
- Ressourcenmanagement (1)
- Resuspension (1)
- Retail trade (1)
- Risk assessment (1)
- Roman Climate Anomaly (RCA) (1)
- Ruhrgebiet (1)
- Ruland / Vooružënnye Siss (1)
- Russia (1)
- SAR‐OSL dating (1)
- SEM-EDX (1)
- SW Baltic Sea (1)
- Satellitenbildauswertung (1)
- Scandinavian Ice Sheet (1)
- Schaalsee (1)
- Schutzgebiete (1)
- Schutzgebietseffektivität (1)
- Schutzgebietsmanagement (1)
- Seafloor Roguhness (1)
- Sedimentologie (1)
- Sedimenttransport (1)
- Seespiegelschwankungen (1)
- Seismik (1)
- Sentinel 2 (1)
- Sewage (1)
- Siberia (1)
- Sibirien (1)
- Site selection process (1)
- Social Research (1)
- Soziale Vulnerabilität (1)
- Sozialökologie (1)
- Sozio-ökonomische Entwicklung (1)
- Special-Use Forests (1)
- Spectral unmixing (1)
- Stadial (1)
- Standortauswahlgesetz (1)
- Statistical modelling (1)
- Stickstoffdüngung (1)
- Stockholm Convention (1)
- Structural analysis (1)
- Strukturgeologie (1)
- Sustainability Development Goals (SDG) (1)
- Sustainable Agriculture (1)
- Sustainable Development (1)
- Sustainable food systems (1)
- Sustainable production and consumption (1)
- Sustainable use of resources (1)
- Synthetic sandstone (1)
- Südafrika , Schwermetall , Mikroplastik , Pestizid , Sediment , Bioindikation , Umwelttoxizität , Seismik , Hexachlorcyclohexan , DDT (1)
- TESZ (1)
- TTZ (1)
- Tektonik (1)
- Teleostei (1)
- Thermische Analyse (1)
- Thin-skinned thrust tectonics (1)
- Thyreophora (1)
- Tiefenlager (1)
- Tierische Lebensmittel (1)
- Toarcian (1)
- Toarciconiopteryginae (1)
- Ton-Eisen interaktion (1)
- Tonmineral (1)
- Tonmineralogie , Diagenese , Sandstein , Porosität , Permeabilität (1)
- Topographie (1)
- Topography (1)
- Totholz (1)
- Touristische Karten der DDR (1)
- Transformationsländer (1)
- Transienten-Elektromagnetik (1)
- Transportprozesse (1)
- Treibhausgasemissionen (1)
- Trophie (1)
- True Cost Accounting (1)
- True Cost Accounting (TCA) (1)
- Typha (1)
- UNESCO-Biosphere reserve (1)
- UNESCO-Biosphärenreservat (1)
- USO-Project (1)
- Umwelt (1)
- Umweltbildung (1)
- Umweltökonomie (1)
- Urban green areas (1)
- V. parcedentata (1)
- Vallonia tenuilabris (1)
- Variogram (1)
- Variogramm (1)
- Vereisung (1)
- Vergletscherung (1)
- Verkehr (1)
- Verkehrsgeographie (1)
- Verlag (1)
- Verlagsgeschichte (1)
- Vertigo genesii (1)
- Volumenbilanz (1)
- Voronoi tessellation (1)
- Vulnerabilität (1)
- Wahrnehmung (1)
- Wahrnehmung von Waldwerten (1)
- Wald (1)
- Waldschaden (1)
- Waldschäden (1)
- Wasserknappheit (1)
- Wassernachfrage (1)
- Wasseroberfläche (1)
- Wasserspiegelschwankungen (1)
- Wassertiefe (1)
- Water scarcity (1)
- Water-rock interaction (1)
- Waterberg Distrikt (1)
- Watt (1)
- Wattenmeer (1)
- Way of St. James (1)
- Wechsellagerung (1)
- Weichseleiszeit (1)
- Weichselian (1)
- Weichselvereisung (1)
- Weichtiere (1)
- Wiek Fault System (1)
- Wirbeltiere (1)
- Wirtschaft (1)
- Wirtschaftsgeografie (1)
- Wissen (1)
- Wälder (1)
- XRF scanning (1)
- Zement (1)
- Zentralasien (1)
- Zentrale Orte (1)
- Zentrum (1)
- Zoobenthos (1)
- acceptance (1)
- acoustic backscatter (1)
- agency (1)
- agri-food (1)
- akustische Rückstreustärke (1)
- alkali-activation (1)
- alternative Reiseformen (1)
- analysis (1)
- angiosperms (1)
- autoregressive conditional heteroskedasticity (1)
- baselevel-Zyklizität (1)
- beach ridge (1)
- beach ridge stratigraphy (1)
- biogeography (1)
- biologische Vielfalt (1)
- biomarkers (1)
- biophysikalischer Parameter (1)
- biosphere reserve (1)
- bitumen (1)
- body size (1)
- buffer zone (1)
- business travel (1)
- calcium-rich hardwater lakes (1)
- capability approach (1)
- catalogue of criteria (1)
- charcoal (1)
- clay mineral (1)
- clay-iron interaction (1)
- climate awareness (1)
- climate behavior (1)
- climate conditions (1)
- climate elasticity (1)
- climate fluctuations (1)
- climate protection (1)
- climate variability (1)
- coalification (1)
- coastal evolution (1)
- coastal geomorphology (1)
- collective action (1)
- commuting (1)
- composite ridges (1)
- conservation (1)
- conservation planning (1)
- continental slope (1)
- contourites (1)
- corridor development strategies (1)
- crop production (1)
- deep biosphere (1)
- deep‐marine deposits (1)
- dehydroxylation (1)
- demographic change (1)
- denial (1)
- depositional environment (1)
- destination image (1)
- destination loyalty (1)
- developing countries (1)
- diagenesis (1)
- diatom (1)
- diatoms (1)
- dietary behavior (1)
- digital elevation models (1)
- diversity (1)
- ectogenic meromixis (1)
- electromobility (1)
- environmental psychology (1)
- eolian activity (1)
- evaluation (1)
- evaluation of ecological restoration measures (1)
- feasibility (1)
- food geographies (1)
- food markets (1)
- foredune progradation (1)
- forest value perception (1)
- funding data (1)
- geochemistry (1)
- geochronology (1)
- geographical variability (1)
- geology (1)
- geopolymer (1)
- glacier skiing (1)
- glaciers (1)
- glacitectonics (1)
- global production networks (1)
- globalization (1)
- greenfield FDI (1)
- greenhouse gas emissions (1)
- gymnosperms (1)
- high temperatures (1)
- higher education (1)
- home office (1)
- hydration (1)
- ice flow model (1)
- illite/smectite (1)
- information (1)
- interdisziplinär (1)
- interlayers (1)
- interregional migration (1)
- interstratification (1)
- intervention (1)
- keine Angaben (1)
- kerogen (1)
- kulturelle Ökosystemleistungen (1)
- lake-level fluctuations (1)
- lake‐level variations (1)
- land degradation (1)
- land-use (1)
- landscape aesthetics (1)
- landwirtschaftlichen Kulturen (1)
- leaf-wax (1)
- leisure activities (1)
- literature review (1)
- long-term (1)
- low-carbon behavior (1)
- luminescence dating (1)
- luminescence profiling (1)
- luminescence-dating (1)
- ländlich (1)
- maar lake (1)
- marine habitat mapping (1)
- mayor (1)
- media representation (1)
- microbial diversity (1)
- microbial diversity; (1)
- microstructural analyses (1)
- mine drainage (1)
- mobility (1)
- model-based (1)
- monitoring (1)
- morphometrics (1)
- multibeam echosounder (1)
- multilevel perspective (1)
- n/a (1)
- nachhaltige Entwicklung (1)
- natural analougs (1)
- nature conservation (1)
- natürliche Waldentwicklung (1)
- natürliches Analogon (1)
- nearshore bar formation (1)
- network analysis (1)
- northeastern Germany (1)
- nutrients (1)
- ocean history (1)
- ocean sustainability (1)
- organic farming (1)
- organofacies (1)
- ostracodes (1)
- paleoenvironment (1)
- paleoenvironmental changes (1)
- paleomagnetic secular variations (1)
- paludiculture (1)
- participation (1)
- pelagites (1)
- peripher (1)
- petroleum potential (1)
- phenology (1)
- phytoplankton (1)
- place and space (1)
- plate tectonics (1)
- proteced area management effectiveness (1)
- public parks (1)
- pyrolysis (1)
- qualitative Sozialforschung (1)
- qualitative social studies (1)
- radiocarbon dating (1)
- redox-sensitive trace metals (1)
- regional approach (1)
- regional identity (1)
- regional polarization (1)
- regional policy (1)
- regional sustainable development (1)
- replicability (1)
- repository (1)
- reproducibility (1)
- responsibility (1)
- rewetting (1)
- rural area (1)
- salinity changes (1)
- sea-level change (1)
- sediment (1)
- sediment volume (1)
- sedimentology (1)
- selective migration (1)
- self-efficacy (1)
- semi-arid (1)
- semi-arid Mongolia (1)
- smectite alteration (1)
- social-ecologic systems (1)
- social-ecological system (1)
- socio-economic development (1)
- sozial-ökologische Systeme (1)
- spatial analysis (1)
- spatial prioritization (1)
- specific dissolution potential (1)
- specific surface area (1)
- spezifische Oberfläche (1)
- spezifisches Auflösungspotential (1)
- structural analysis (1)
- structural evolution (1)
- summer skiing (1)
- surface exposure dating (1)
- sustainability (1)
- sustainability transitions (1)
- sustainable consumption (1)
- sustainable developmental role (1)
- sustainable transformation (1)
- swelling (1)
- tectonic reconstruction (1)
- tephra layers (1)
- text mining (1)
- time series (1)
- tourist satisfaction (1)
- turbidites (1)
- universities (1)
- urban geography (1)
- validation (1)
- value chains (1)
- vegetation decomposition (1)
- volatility (1)
- vulnerability (1)
- waste repositories (1)
- water column (1)
- water content (1)
- water–rock interaction (1)
- wells (1)
- Änderung (1)
- Ökobilanz (1)
- Ökologie (1)
- Ökosystemdienstleistungen (1)
- Ökotourismus (1)
- ‘Little Ice Age’ (LIA) (1)
Institute
- Institut für Geographie und Geologie (145) (remove)
Publisher
- MDPI (20)
- Springer Nature (14)
- Copernicus (12)
- Frontiers Media S.A. (5)
- Wiley (5)
- SAGE Publications (2)
- De Gruyter (1)
- Elsevier (1)
- Nature Publishing Group (1)
Global change is one of the major challenges our society faces in recent times and is becoming increasingly noticeable in all aspects of our lives. In the last ten years, reports about droughts in Europe increased, contrary to expected natural climate variations and are attributed as indicators of climate change. Droughts resulted in a severe decrease in water levels of lakes, rivers and reservoirs, posing socio-economic and environmental challenges. Climate scenarios by the Intergovernmental Panel on Climate Change (IPCC) project increasing temperatures, more frequent, longer and/or more intense heat waves and warm spells, and an increase in aridity with short-term droughts in the upcoming decades for Western and Central Europe. Some areas – such as Northeast Germany – are already affected by negative water balances and the lowering of lake and groundwater levels. Additionally to possible challenges in water availability, excess nutrients and heavy metals from industrial emissions, agricultural fertilisers and land use changes lead to declining water quality. In the past century, extensive eutrophication and environmental pollution have become major water quality issues in many freshwater bodies.
Nonetheless, water and its availability in a sufficient quantity and quality are prerequisites for life and must be prioritised in future development. The European Union aims for a good status in all surface and groundwater bodies by 2027 regarding their ecological, chemical and quantitative status. However, a profound understanding of eutrophication, pollution sources, and water bodies' reference conditions – referring to pre-anthropogenic conditions – should be available for each system to apply integrated restoration strategies. Moreover, an in-depth understanding of long-term climate variability and its dynamics is indispensable to approach these climate change challenges and reliably predict water availability.
During the past decades, numerous paleoenvironmental studies have been carried out on Northern German sediment archives, using mainly lacustrine sediments to reconstruct hydroclimatic variability, often inferring lake-level variations as key indicators. However, most studies were carried out in areas affected by more maritime or continental climate. Studies from the transition zone are rare. Only few existing studies offer high-resolution records and/or robust chronologies, which limits the understanding of past environmental changes significantly. Besides, the Northern German lowlands have been anthropogenically affected since at least the Neolithic (~5.6 ka cal BP) and, in particular, forest composition and density have recently been shown to have at least partially an impact on lake-level variations. However, a reliable distinction between climatic impacts and anthropogenic interferences is widely missing, which is a problem because many studies were conducted on rather small lacustrine systems in which expected anthropogenic signals are higher, and single events may overprint the climatic signals. These biases lead to an incoherent picture of the past hydroclimatic variability in Northern Germany during the Holocene. To overcome this situation, it is inevitable to identify a suitable sedimentary archive from the transition zone – preferably a large lacustrine system in which natural (supra-)regional paleoenvironmental signals are expected to be not overprinted by single events. Moreover, it is necessary to establish robust chronologies and apply high-resolution methods to infer past environmental changes in a high temporal resolution. Taken together, this could contribute to an enhanced understanding of past environmental and climatic changes in Northern Germany.
This thesis consolidates the evidence for Schweriner See to act as a suitable sedimentary archive in Northern Germany for (supra-)regional climate reconstructions. Schweriner See is a large lowland lake in Northern Germany located within the transition zone from maritime to continental climate. In the first step, (paleo)lacustrine landforms, i.e. beach ridges, subaerial nearshore bar, and a silting-up sequence, are investigated along the north-eastern shoreline using a combined approach of sedimentology (e.g. grain size variations) and the relatively novel method of luminescence profiling offering relative age determinations to understand depositional processes and their chronological framework. Absolute age information is mainly inferred by OSL dating. Secondly, an important prerequisite to interpreting information obtained from lacustrine sediment archives is a thorough understanding of processes controlling sedimentation. Schweriner See is characterized by a complex morphometry, which influences in-lake processes, i.e. i) in-lake productivity, ii) carbonate precipitation and iii) wind- and wave-induced processes, resulting in a distinct spatial heterogeneity. This thesis shows that it is crucial first to understand sedimentary depositional processes and controlling mechanisms to i) select suitable coring location(s) and ii) reconstruct paleoenvironmental and hydroclimatic variations reliably.
Based on bathymetric considerations and inferred in-lake processes, two main coring locations were identified to infer i) the anthropogenic impacts and ii) hydroclimatic variations. Short sediment records from the shallow water areas (< 15 m water depth) cover the most recent environmental history of Schweriner See. A well-dated sedimentary record (210Pb/137Cs and 14C dating) links distinct sedimentary and geochemical changes with historical events. Schweriner See was extensively affected by lake-wide eutrophication and contamination, closely related to sewage and population dynamics within the catchment. The water quality only improved after the German Reunification in 1990 CE when sewage was precluded from Schweriner See. Contamination trends at Schweriner See showed similar trends to different archives along the southern Baltic Sea, implying a common regional driving mechanism, e.g. environmental legalisation.
A well-dated sediment record from the profundal zone (52 m water depth) allowed the reconstruction of large-scale atmospheric conditions during the past 3 ka cal BP by inferring winter temperature variability, the moisture source region and/or evaporative lake water enrichment, which resemble variations in the North Atlantic Oscillation (NAO). The NAO greatly influences the Central European climate, affecting, for example, surface air temperature, precipitation or storm tracks. During 3-2.8 ka and 2.1-0.8 ka cal BP, predominantly positive NAO conditions are reconstructed, which are characterized by warmer winter temperatures, moisture conditions bringing isotopically enriched precipitation from the southern/central North Atlantic to Northern Central Europe and/or warmer temperatures that may result in a higher evaporative isotopic lake water enrichment as a result of northwards displaced westerlies. Conversely, during 2.8-2.1 ka and 0.8-0.1 ka cal BP, results correspond to predominantly negative NAO phases influenced by southwards displaced westerlies. Frequent atmospheric blocking allows for the intrusion of northerly or easterly winds, resulting in colder winter temperatures, isotopically depleted precipitation from the Northern Atlantic and Arctic region and/or a lower evaporative lake water enrichment. In addition to these long-term changes in atmospheric conditions, short-term hydroclimatic variations have been reconstructed, mainly reflecting lake-level variations in conjunction with precipitation variability, with the proxy signal being additionally amplified by wind speed and wave motion. Comparisons with other archives support these results.
So far, the paleoenvironmental reconstruction is limited to the Late Holocene, but initial dating results imply possible interferences until the Late Pleistocene. Therefore, future studies should focus on extending the profundal record from Schweriner See further back in time, providing a high-resolution record covering both the Holocene and possibly the Late Pleistocene.
The dissertation looks at bioeconomy innovation at different levels through the lens of economic geography. By progressing from the meta to the micro-scale, it tries to find answers to how the interrelated concepts of bioeconomy and innovation are embedded in these respective contexts while consecutively concretising bioeconomy and de-fuzzing it. To do that, it adopts a mixed-methods approach that starts general and ends specific, going from the meta-scale of literature over the macro-scale of three distinct areas in which bioeconomy is discussed to the meso-level of central actors of a European funding network before, lastly, considering case studies at the micro-scale. Throughout, the thesis aims to spatialise the bioeconomy by shedding light on the term and its drivers across multiple geographic layers. It thereby not only offers new insights into dimensions of innovation in the bioeconomy but also contributes to the discipline of economic geography by applying some of its essential theoretical ideas to an emerging political framework.
Seas and oceans are essential for the global ecosystem. Entire societies, economies and countless livelihoods rely on their good environmental status. Yet, pressures on marine environments are increasing. An extensive assessment and monitoring of marine habitats is a vital precondition for understanding these systems and their sustainable conservation. Remote sensing methods can temporally accelerate the mapping, improve the spatial resolution and support the interpretation of large areas. Hydroacoustic becomes the method of choice for areas deeper than the coastal zone as optical signals are limited by strong attenuation in the water column. Apart from depth measurements for the creation of bathymetric charts, the recording of backscatter strength is useful for the characterization of the seafloor surface. The direct influence of the inhabiting benthic community on the backscattered signal is rarely considered, although it can be utilized for the detection of benthic life. Information about habitat-specific backscatter responses or a hydroacoustic remote sensing catalog for benthic habitats is missing so far.
The multibeam echosounder (MBES) has the advantage of recording both, bathymetry and backscatter strength simultaneously with related incidence angle. Further, recent technological developments allow to change between frequencies. Angular range curves supported the quantification of backscatter strength of different frequencies. Acoustic data sets were complemented by ground truthing in form of sedimentological and biological samples as well as video profiles. Study areas were located offshore the island of Sylt in the North Sea as well as in vicinity to Oder Bank and close to the coast offshore Hohe Düne/Rostock, both in the Baltic Sea. Investigated habitats included sand areas inhabited by tubeworms, loose mussel clusters on top of sand areas, seagrass meadows, coarse sand and gravel areas, and a reef covered by mussels.
Multifrequency backscatter maps, combining frequencies between 200 kHz and 700 kHz, illustrate small-scale features at the seafloor not visible in monofrequent maps. Key habitats showed a specific backscatter response, which can partly be related to macrobenthic flora and fauna. Data sets recorded with a (partly calibrated) MBES in three different month (May, August, October) revealed that backscatter strength can further detect spatial as well as temporal habitat dynamics. Alterations in the sediment composition at the seafloor surface of the ecologically valuable coarse sand and gravel areas were caused by seasonal changes in local hydrodynamics.
A newly developed 3D seismic lander has the ability to support hydroacoustic remote sensing as an additional, non-destructive ground truthing method utilizing a high frequency of 130 kHz to image the shallow subsurface. Buried objects, e.g., stones, shells, fruit gummy worms, as well as sediment disturbances could be detected and visualized in a laboratory experiment. The 3D seismic lander is likely to improve the investigation of volume scatter contribution to backscatter strength and is potentially applicable for the imaging of bioturbation.
The deep geological underground represents an important georesource for the short-
term storage of renewable energy and the long-term reduction of greenhouse gas emissions. To ensure the economic viability and safety of any subsurface storage project, detailed characterisation of the quality and integrity of the reservoir and its cap rock is required. This characterisation includes the accurate determination of the petrophysical properties, such as porosity and permeability, as well as the potential mineral reactions, such as the dissolution of reactive phases, which may occur during the lifespan of such a project. Clay minerals are common components of many reservoir systems and, depending on their type and structure, can have a significant impact on storage and transport properties. These processes are, however, currently not well understood. In order to address these issues, the main focus of this thesis is on mineralogical analyses using X-ray diffraction (XRD) and microstructural studies using focused ion beam scanning electron microscopy (FIB-SEM) together with micro X-ray computed tomography (µXCT) to gain a better understanding of the influence of clay minerals on reservoir and cap rock properties.
A central part of this thesis focuses on the analysis of clay minerals and pore structures of the Bebertal Sandstone of the Parchim Formation (Early Permian, Upper Rotliegend), which is considered a natural analogue for the tight reservoir sandstones of the North German Basin. Two illite polytypes with a variety of characteristic structures have been identified in the Bebertal sandstone. Disordered 1Md illite forms the majority of the observed structures, which include omnipresent grain coatings, altered permeable feldspar grains and pore-filling meshwork structures. Trans-vacant 1M illite represents the second and youngest generation of authigenic illite and occurs as fibrous to lath-shaped particles that grew into open pore spaces and led to a significant reduction in porosity and permeability during late diagenesis. Based on these results, a model for the formation of illite polytypes in the aeolian layers of the Bebertal sandstone was developed that describes the temporal and spatial evolution of porosity and permeability during diagenesis. Information from this model was then used to improve the prediction of permeability of the Bebertal sandstone based on µXCT pore space models and direct numerical simulations. To achieve this, a micro-scale pore space model was created that allowed the simulation of permeability reduction by clay minerals by including nanoporous illite domains based on a novel morphological algorithm. By performing Navier-Stokes-Brinkman simulations, more accurate predictions of permeabilities with respect to experimentally determined values were obtained compared to conventional Navier-Stokes simulations.
The detailed characterisation of the Bebertal sandstone has shown that natural reservoir rocks are usually complex heterogeneous systems with small-scale variations in texture,
composition, porosity and permeability. Flow-through experiments on the Bebertal sandstone revealed that the coupled geochemical and hydrodynamic processes that occur during the dissolution of calcite could not be predicted by reactive transport models. Therefore, as part of this thesis, a novel approach for developing synthetic sandstones at low temperatures based on geopolymer binder was developed. It is shown that simpler and more homogeneous porous materials can be produced with porosity and permeability values in the range of natural sandstones. These can be used to better understand the dynamic and coupled processes relevant to the storage of renewable energy in reservoir rocks through improved experimental constraints.
The final part of this thesis reports on a detailed clay mineral and pore space study of
three shale formations and one mudstone that were identified as potential seals for the Mt. Simon sandstone reservoir in the Illinois Basin. During the Illinois Basin - Decatur Project, this reservoir was used for the sequestration of one megaton of supercritical carbon dioxide. In order to better assess the quality of the sealing units and to better understand the role of the intergranular clay mineral matrix as potential pathway for fluid migration, a multi-scale evaluation was conducted that included thin section analysis, quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN), mercury intrusion capillary pressure (MICP) measurements, quantitative XRD and high-resolution FIB-SEM. The results allow for the classification of the studied formations into primary and secondary seals and emphasise the importance of three-dimensional clay-mineral-related pore structure characterisations in cap rock studies. XRD proved the most reliable method for the identification and quantification of clay minerals in the studied cap rocks and mudstones. In contrast, FIB-SEM and QEMSCAN provided the spacial constraints for reconstructing fluid flow pathways within the clay mineral matrix.
Overall, this thesis highlights the importance of the precise identification of clay minerals in geological reservoirs and their cap rocks. It also illustrates the need for three-dimensional characterisation and modelling of the associated small pore structures for an improved understanding of the rocks diagenetic history as well as the prediction of the transport and storage properties of these crustal reservoir systems.
The skull is an extremely informative part of the vertebrate body. Skulls are
involved to hunt, feed and drink, to nurse, fight, dig, and to many other activities.
Also, main sensory organs are situated on the head in order to enable a given
animal to see, smell, taste, feel, listen, equilibrate and think; hence, the head is the
main connection to the external world. It follows that a skull, with and without soft
tissue, can tell a lot about its owner. Each skull consists of many individual bones
constituting regions (e.g., snout and braincase) that represent different aspects of an
anatomical mosaic, which in turn allows deeper (palaeo)biological insights.
In the past three centuries, palaeontologists dug out countless fossils from all
over the world and from many preserved periods and groups, including dinosaurs.
Hence, public and private collections house numerous fossil skull specimens. To
further enlighten our understanding of palaeoecological, physiological and
phylogenetic affinities of dinosaurian representatives belonging to different groups,
and in order to reveal new aspects on their (neuro)anatomy, behaviour, ontogeny
and evolution, a thoroughly examination with modern techniques is the aim of this
thesis.
In order to get a phylogenetically broad understanding, fossil remains from at
least four extinct species, including Irritator challengeri (a theropod: mostly bipedal
carnivores) from the Early Cretaceous of northeastern Brazil, Europasaurus holgeri
(a sauropod: long-necked, quadrupedal herbivores) from the Late Jurassic of Lower
Saxony, Emausaurus ernsti together with an unnamed taxon from the Early Jurassic
of Mecklenburg-Western Pomerania, and Struthiosaurus austriacus, Late
Cretaceous of eastern Austria (the latter three are thyreophorans: armoured, mostly
quadrupedal herbivores), were in closer focus. To document and digitally reconstruct
cranial bones and cavities therein, the material was examined with micro computed
tomography (microCT). On this basis, the full morphology of the preserved anatomy
was revealed, described and contextualized, for example, in conjunction with
comparative anatomy and biomechanical considerations. During this process, further
methods were used to investigate and depict individual fossils: macro- and microphotography,
photogrammetry and phylogenetic analyses, each encompassing
multiple sub-tasks and being supported by 3D prints.
As part of the result, it was possible to formulate reasoned assumptions about
the lifestyle of the taxa in focus. For instance, the neuroanatomy and the osteological
characteristics of the spinosaurid Irritator challengeri implicate that this taxon was an
agile hunter with a habitually inclined snout that was specialized in catching relatively
small prey with a robust dentition and a comparably weak - but fast - bite, with a
remarkable jaw mechanism which enabled the animal to kinetically widen the
pharynx during lower jaw depression. The (neuro)anatomy of I. challengeri, S.
austriacus, E. ernsti and E. holgeri presented here, enrich our knowledge about a
plethora of (lifestyle-related) aspects of these animals, their closer relatives and the
prehistoric world they lived in.
This work first sets out to find if economic, ecological, or social incentives drive consumers towards or against dietary decisions (Contribution A). It then develops a framework of TCA for food to describe economically conveyed incentives that are tied to ecological and social indicators within the food market (Contribution B). The framework is subsequently enhanced and broadened to include a deeper understanding and broader field of indicators for more holistic TCA calculations (Contributions C and D). Lastly, based on these calculations, TCA of food is implemented in a factual use case as the framework and calculations are deployed for commodities of a German supermarket chain; then consumer, as well as expert feedback is used for the discussion on socially responsible campaigning and policy change (Contribution E).
Der Begriff Nachhaltigkeit hat längst Eingang in den deutschen Sprachgebrauch gehalten. Doch
wie verhält es sich mit dem Verständnis zum Paradigma Nachhaltigkeit, welches sich im
soziologischen, ökonomischen und ökologischen Wirkungsgefüge bewegt? Aufgrund ihrer
sozialen Relevanz, ihrer distributiven Verflechtungen und ihrer Bedeutung für den
Wohlfahrtsstaat kommt Unternehmen eine große Bedeutung zu. Hilfreich für die Erforschung
des komplexen und dynamischen Nachhaltigkeitsprozesses sind individualisierte Sichtweisen in
räumlichen Abgrenzungen. Biosphärenreservate, die weltweit von der UNSECO als
Modellregionen für nachhaltige Entwicklung als solche anerkannt wurden, bieten sich hierfür
an. Die übergeordnete Forschungsfrage dieser Arbeit lautet daher: Wie wird in den UNESCOBiosph
ärenreservaten die nachhaltige Entwicklung, speziell verantwortungsvolles Wirtschaften,
exemplarisch verwirklicht?
Eine Einordnung in den Nachhaltigkeitsdiskurs zeigt aktuelle Perspektiven auf und stellt die
Nachhaltigkeitsforschung im Kontext der Biosphärenreservate sowie die Bedingungen für
verantwortungsvolles Wirtschaften vor. Als forschungsrelevante Zielgruppen wurden die
Verwaltungen der UNSECO-Biosphärenreservate (BR), Multiplikatoren der Wirtschaft (z.B.
kommunale Wirtschaftsförderungen, IHK, Handwerkskammern, Bauern- und
Wirtschaftsverbände) sowie Unternehmen in bzw. an BR identifiziert. Mithilfe von
leitfadengestützten Experteninterviews und hybriden Fragebögen erfolgte die Datenerhebung,
die mit der Grounded Theory bzw. grafisch ausgewertet wurden.
Die Datenerhebung hat gezeigt, dass BR-Verwaltungen bislang überwiegend für
Umweltschutzbelange mandatiert und für die Einflussnahme hinsichtlich verantwortungsvollen
Wirtschaftens auf Kooperationspartner angewiesen sind. Wirtschaftsbezogene Aktivitäten sind
innerhalb ihrer Netzwerke der Partnerbetriebe etabliert, sie fokussieren überwiegend die
Direktvermarktung regionaler Produkte und die Inwertsetzung der naturverträglichen
Tourismusangebote. Innerbetriebliche Prozesse werden von einigen BR-Verwaltungen mit
Beratungsangeboten zu Umweltmanagementsystemen (z.B. EMAS) begleitet. Etliche BR weisen
wenn überhaupt nur einen geringen Besatz an Industrie- oder Dienstleistungsunternehmen, ihre
Verwaltungen haben daher auch kaum Berührungspunkte zu den Betrieben des sekundären und
tertiären Sektors außerhalb der Tourismusbranche. Die auf repräsentative Kulturräume
ausgerichteten Zonierungskonzepte der BR können diesbezüglich überdacht werden. Deutlich
wird, dass Handlungskompetenzen in wirtschaftsorientierten Themenkomplexen (Beratung zu
Fördermöglichkeiten, Innovationen, Technologieanwendung, Unternehmensgründung, mobiles
Arbeiten, Aus- und Weiterbildung, Vereinbarkeit von Beruf und Familie, Fachkräftesicherung,
Zertifizierungen, Produktentwicklung, Prozessoptimierung, Digitalisierung) nach Institutionen
durch die Wirtschaftsvertreter überwiegend den IHK, den Handwerkskammern und
Wirtschaftsförderungen und weniger den BR-Verwaltungen zugeschrieben werden.
Mehrheitlich beurteilen die befragten Unternehmen die Handlungsfähigkeit von BRVerwaltungen
hinsichtlich des Naturschutzes, der Vermarktung regionaler Produkte und
Dienstleistungen sowie von Agrarumweltmaßnahmen positiv. Dagegen ist den Unternehmen
die Handlungsfähigkeit der BR-Verwaltungen auf den Gebieten der Verkürzung von
Planungsverfahren, der Prozessinnovation, des Energiemanagements und der
Fachkräftesicherung weitestgehend unbekannt. Eine große Mehrheit der Unternehmer meint
zudem, dass sich die Ziele und Aktivitäten der BR-Verwaltungen vorrangig auf
Naturschutzmaßnahmen beziehen. Weiterhin meinen sie, richtet die sich die Unterstützung von
Unternehmen überwiegend auf die Vermarktung regionaler Produkte und traditionelles
Handwerk. Die 17 Nachhaltigkeitsziele der Vereinten Nationen haben bislang keinen
breitenwirksamen Bekanntheitsgrad in der befragten Unternehmerschaft gefunden.
In einem integrierten Verständnis fließen ökologische und soziale Aspekte der Nachhaltigkeit in
die konzeptionellen Grundlagen der BR ein, die ökonomische Dimension dagegen reduziert sich
oft auf die Bereiche Landwirtschaft und Tourismus. Weiterführende Aktivitäten hinsichtlich
nachhaltigen Wirtschaftens überlassen BR-Verwaltungen derzeit überwiegend der Expertise
wirtschaftsfördernder Institutionen, die sich aus ihrer Sicht originär mit innerbetrieblichen
Prozessen befassen.
Der Austausch von Grundlagendaten oder Ergebnissen bisheriger Datenerhebungen zwischen
den BR-Verwaltungsstellen – einem potenziellen Wesensmerkmal von Modellregionen – wird
durch das Fehlen entsprechender Infrastruktur deutlich erschwert, bzw. ist nicht möglich.
Technische und personelle Ressourcen für die digitale Datenaufbereitung und -pflege in den BRVerwaltungen
sind überwiegend nicht vorhanden.
Mit der Anerkennung eines BR durch die UNESCO muss auch seine Anerkennung als
Modellregion für nachhaltige Entwicklung durch alle beteiligten Interessengruppen
einschließlich seiner Bewohner einhergehen.
Underground hard coal mining operations irreversibly disrupt the pre-existing mechanical equilibrium of the geological media. The employment of high-recovery methods modifies the stress field of the sedimentary sequence, generating movement and faulting of the rock layers above and below mined seams. These new fracture zones do affect the original conditions of the hydrogeological system by modifying flow pathways and increasing the permeability of the rock sequence. Moreover, the surface area of rock exposed to air and water is increased, conditioning the water-rock interaction. Despite this rather clear conceptualization, flow and reactive transport processes in fractured overburdens are rarely modeled simultaneously. Discrete setups that consider fractures and porous matrix require extensive characterization of both media, which is impractical for regional case studies. As a result, most post-mining models explicitly ignore fracture structures by employing the equivalent porous approach or even both media with lumped parameter models. However, omitting either medium represents a delicate simplification, considering that mining-related fractures control the rate and direction of water flow within moderately permeable but relatively highly porous rock sequences.
In this dissertation, the specific contribution of fractured and matrix continua to the transient discharge and water quality of a post-mining coal zone is quantified and evaluated. For this purpose, dual and multiple interacting continua models are employed to simulate fluid flow and reactive mass transport in fractured and variable water-saturated rock sequences. The effectiveness of the models is evaluated by simulating the origin, generation and transport of acid mine drainage (i.e., water with elevated concentrations of hydrogen, iron, sulfate and chloride) within the shallow overburden of the Ibbenbüren Westfield. Compared to other coal districts in Germany, this area is strongly delimited by the local geology and topography, resulting in a well-defined hydrogeological system to test the models. Petrographic and chemical analyses performed on core samples from the area show the strong influence of mining-derived fractures on the water-rock interaction within the Carboniferous sequence. The presence of oxidized pyrite along with amorphous iron hydroxide phases in weathering fronts on both sides of the fractures demonstrates the exchange of solutes and gases between the fractured and the porous matrix media.
Based on the previous evidence, the TOUGHREACT software is employed to characterize flow and reactive transport processes in the Westfield. However, each of the two processes is simulated at separate stages to have more control in the adjustment of sensitive parameters for which little information is available. For the flow component, a dual continuum model, with Richard’s equations is used to characterize the unsaturated water flow in both fractured and matrix media. Under this approach, the model adequately reproduces the bimodal flow behavior of the discharges measured in the mine drainage for the years 2008 and 2017. Simulation results show how the fractured continuum generates intense discharge events during the winter months while the rock matrix controls smooth discharge limbs in summer, when water is slowly released back to the fractures. With the flow component calibrated, the second part of the study incorporates the geochemical processes into the model based on actual data from the rock samples. Their simulation requires extending the two-continuum setup to a multiple continua model with five nested block strings: one for the fractures and four for the rock matrix. This further subdivision prevents under-representations of kinetic reactions with short equilibrium length scales and numerical instabilities due to lack of chemical and flow gradients. As a result, the new multiple continua model provides good agreement with respect to long- and short-term concentrations and discharge trends measured in the mine drainage. The flow of oxygen and meteoric water through the fractured continuum leads to a high and steady release of hydrogen, iron and sulfate ions derived from pyrite oxidation in the matrix continua closest to the fractures. Moreover, high chloride concentrations result from the mixing and gradual release of relatively immobile solutes in the matrix as they interact with percolating water in the fracture. Both findings are equally congruent with the reactive pyrite oxidation and iron hydroxide precipitation fronts identified in the fractured core samples.
In the end, the multiple continua models, the simulation procedure and the results of the benchmark and sensitivity analysis scenarios developed for the Westfield pave the way for the application of the approach in other mining zones. The first candidate emerges in the Ibbenbüren Eastfield, where a coupled elemental-isotopic approach included in this thesis has confirmed that water-conducting fracture zones are primary elements for solute generation and transport in the first 300 meters of the overburden. In the latter case, calibration and verification of the models can be complemented with measurements of δ34S in sulfates and δ18O, δ2H, and Tritium in water.
Autoclaved aerated concrete (AAC) is a building material that combines heat insulation
properties with sufficient mechanical strength for masonry construction. Compared to
ordinary concrete, the matrix is highly porous (>50%) and hardened by a hydrothermal curing
process at 150°C - 200°C. During this process, quartz sand and portlandite react to form first
calcium silicate hydrates (C-(A)-S-H) with Ca/Si ratios <1.3 and then tobermorite. Especially
tobermorite, which has a much larger crystallite size than C-(A)-S-H, provides improved
mechanical strength. This reaction sequence is influenced by many parameters and
additives of which calcium sulfate is probably the most important. Despite several attempts to
investigate these hydrothermal reactions, the actual reaction mechanism involved when
adding sulfate ions is not fully understood. It has been suggested that the addition of ca.
1.5 wt% significantly improves the mechanical properties due to the enhanced formation and
arrangement of tobermorite in the porous matrix. Since the sulfate content in AAC waste is
exceeding regulatory threshold for low-quality reuse in some countries, the aim of this study
was to investigate in detail the reaction mechanisms involving sulfate addition. Such
knowledge may open up the possibility to improve AAC production and to avoid the need for
sulfate addition. To achieve this goal, this research work focused on investigating the
hydrothermal curing process to determine the sequence of hydrothermal reactions and the
spatial distribution of the phases formed. For this purpose, a new setup for in situ X-ray
diffraction was specifically designed to study hydrothermal reactions and to conduct time
intensive experiments on a normal laboratory diffractometer. In order to quantitatively
evaluate the in situ measurements by Rietveld analysis using TOPAS, it was also necessary
to develop atomistic structure models for C-(A)-S-H phases. This was made possible by
adopting a supercell approach that was previously used to describe turbostratically stacked
clay minerals. The structure models, derived from tobermorite, are placed in an otherwise
empty supercell to simulate the C-(A)-S-H nanostructure. Adopting these methodological
advances, it was possible to obtain absolute phase quantities from in situ data and to track
the reaction kinetics of the hydrothermal curing process. These results were then combined
with ex situ X-ray diffraction and scanning electron microscopy. Confirming previous studies,
the major effect of sulfate ions was the formation and decomposition of hydroxylellestadite. It
was further revealed that C-(A)-S-H formation was delayed during hydroxylellestadite
formation, which is supposed to support the silicate ion diffusion and hence the tobermorite
formation at a stage critical for improved hardening of AAC. This can be linked to the
formation of lower amounts of capillary pores in the range of 1-5 µm, as observed by
scanning electron microscopy, and therefore a lower concentration of inherent defects that
resulted in the improved mechanical properties. This research work highlights how important the spatial distribution of crystallites is for the properties of a building material and how this
distribution can be influenced by small alterations in reaction chemistry.
Die Herausforderungen des globalen Klimawandels stehen seit mehreren Jahrzehnten auf der gesellschaftlichen und politischen Tagesordnung. Die Folgen der Erderwärmung haben das Potential, die heute bestehenden ökologischen, sozialen und wirtschaftlichen Systeme in unbekanntem Ausmaß zu stören. Ungeachtet dieser Tatsache bleibt die mediale Aufmerksamkeit auf das Thema größtenteils überschaubar. Das Ziel der Arbeit ist es, ein Bild der Tagesschau Medienagenda im Jahr 2022 zu zeichnen. Im Fokus steht hierbei die Berichterstattung über die Klimakrise im Verhältnis zu anderen sozio-ökonomischen Krisen, wie der COVID19-Krise, der Wirtschaftskrise, der Energiekrise und dem Angriffskrieg gegen die Ukraine. Zur inhaltlichen Auswertung der Tagesschau-Hauptsendung wurde eine qualitative Inhaltsanalyse durchgeführt. Über theoretische Annäherungen, wie den Agenda-Setting-Ansatz und den Framing-Ansatz, konnten Rückschlüsse über die Medienwirkung und das Verhältnis der Krisen zueinander getroffen werden. In der computerbasierten Auswertung mit MAXQDA wurde herausgestellt, dass die Klimakrise mit anderen gesellschaftsrelevanten Themen um Sendeplätze konkurriert. Vor allem der Kriegsausbruch in der Ukraine dominierte die Berichterstattung im Jahr 2022. Darüber hinaus wurde die Klimakrise in der Tagesschau vor allem als Thema politischer Konflikte geframed. Im Jahr 2022 war außerdem der Frame der Klimakrise als Teil multipler Krisen präsent. Dieser suggerierte eine Gleichwertigkeit aller aufkommenden Konflikte, welche der Klimakrise und ihren tiefgreifenden Folgen nicht gerecht wird. Um diese Rolle angemessen zu berücksichtigen, muss der Journalismus innovative Wege finden, um eine ressortübergreifende Berichterstattung des Themas zu erreichen. Nur so können die komplexen wissenschaftlichen Erkenntnisse über die Erderwärmung als Basis für die dringliche Abmilderung der Klimakrise vermittelt werden. Verschiedene Ansätze einer solchen Berichterstattung werden diskutiert.