Filtern
Erscheinungsjahr
Dokumenttyp
- Dissertation (245) (entfernen)
Sprache
- Englisch (245) (entfernen)
Schlagworte
- Pestizid (6)
- Pflanzenschutzmittel (5)
- Landwirtschaft (4)
- Software Engineering (4)
- ecotoxicology (4)
- Biodiversität (3)
- Bodenchemie (3)
- Insektizid (3)
- Nanopartikel (3)
- Pesticides (3)
- Risikoanalyse (3)
- Systematik (3)
- Umweltpsychologie (3)
- model-based (3)
- risk assessment (3)
- soil organic matter (3)
- Abduktion <Logik> (2)
- Abwasserreinigung (2)
- Agriculture (2)
- Anpassung (2)
- Araneae (2)
- Bestäubung (2)
- Biodiversity (2)
- Diffusion (2)
- Ecotoxicology (2)
- Emissionen (2)
- Feldsaum (2)
- GIS (2)
- Genetische Variabilität (2)
- Habitat Fragmentation (2)
- Hydrodynamik (2)
- Kakamega Forest (2)
- Klimawandel (2)
- Kognitive Linguistik (2)
- Maschinelles Lernen (2)
- Modellgetriebene Entwicklung (2)
- Nanoparticles (2)
- Risikobewertung (2)
- Risikomanagement (2)
- Sediment (2)
- Semantic Web (2)
- Sozialpsychologie (2)
- Taxonomie (2)
- Umweltwissenschaften (2)
- Wastewater treatment plants (2)
- agriculture (2)
- aquatic ecotoxicology (2)
- aquatic macrophytes (2)
- decomposition (2)
- diffusion (2)
- eye tracking (2)
- freshwater organisms (2)
- micropollutants (2)
- modelling (2)
- monitoring (2)
- mosquito control (2)
- optimal control (2)
- pesticide (2)
- pesticides (2)
- sorption (2)
- streams (2)
- traits (2)
- wastewater treatment (2)
- Ökosystemdienstleistung (2)
- Ökotoxikologie (2)
- 1H-NMR Relaxometry (1)
- AUTOSAR (1)
- Abbildung <Mathematik> (1)
- Abdrift <Pflanzenbau> (1)
- Absolutismus (1)
- Abwasser (1)
- Abwasserbehandlung (1)
- Acceleration Structures (1)
- Action Recognition (1)
- Action Segmentation (1)
- Ad-hoc-Netz (1)
- Adaptation (1)
- Africa (1)
- Afrika (1)
- Agrochemikalien (1)
- Aktionsart (1)
- Aktiver Wortschatz (1)
- Akzeptanz (1)
- Algorithmische Geometrie (1)
- Amazonia (1)
- Amazonien (1)
- Amphibia (1)
- Anforderung (1)
- Annotation (1)
- Aphid predator (1)
- Aquatic Ecotoxicology (1)
- Aquatic Guidance Document (1)
- Aquatic ecology (1)
- Aquatische Makrophyten (1)
- Aquatisches Ökosystem (1)
- Architektur <Informatik> (1)
- Artificial Neural Networks (1)
- Arzneimittel (1)
- Arzneistoffe (1)
- Aspekt <Linguistik> (1)
- Auchenorrhyncha (1)
- Auditing (1)
- Augenbewegung (1)
- Ausbreitung (1)
- Auslese (1)
- Auswahl (1)
- Automotive Systems (1)
- Autoritarismus (1)
- BPMN (1)
- Basic psychological needs (1)
- Bayes-Netz (1)
- Bayesian Networks (1)
- Beaconless (1)
- Bedrohte Tiere (1)
- Bees (1)
- Befahrbarkeit (1)
- Belebtschlamm (1)
- Benetzung (1)
- Benutzerverhalten (1)
- Beruflicher Kontakt (1)
- Beschichtung (1)
- Bestäuber (1)
- Beta-Blocker (1)
- Beta-Diversität (1)
- Bewertungskriterien (1)
- Bienen <Familie> (1)
- Bildsegmentierung (1)
- Bildverarbeitung (1)
- Bilingualer Unterricht (1)
- Binnengewässer (1)
- Bioassay (1)
- Biohydrogel (1)
- Biopolymere (1)
- Biotransformation (1)
- Biozide (1)
- Bipartiter Graph (1)
- Blickbewegung (1)
- Boden (1)
- Bodenphysik (1)
- Bodenwasser (1)
- Bodenökologie (1)
- Bombina variegata (1)
- Budongo Forest (1)
- Business English (1)
- Business Rule Bases, Inconsistency Measurement (1)
- Butterflies (1)
- Bärlappe (1)
- CLIL (1)
- CSCW (1)
- Calcium (1)
- Carry-over effects (1)
- Cashew-Sektor (1)
- Cations (1)
- Cheilolejeunea ; continental tropical Africa ; rainforest (1)
- Chemische Abwasserreinigung (1)
- Chironomus riparius (1)
- Chromatographie (1)
- Climate (1)
- Climate anxiety (1)
- Climate change (1)
- Climate denial (1)
- Cloud Point Extraction (1)
- Clustering coefficient (1)
- Cognitive functions (1)
- Coleoptera (1)
- Collaboration (1)
- Communication Networks (1)
- Computational Toxicology (1)
- Computer Graphics (1)
- Computer Security (1)
- Computer Vision (1)
- Computer assisted communication (1)
- Computersicherheit (1)
- Conceptual Metaphor Theory (1)
- Connected Vehicles (1)
- Conservation (1)
- Consumer behaviour (1)
- Consumption renunciation (1)
- Content and Language Integrated Learning (1)
- Content and Language Integrated Learning (CLIL) (1)
- Crayfish (1)
- Crayfish plague (1)
- Curriculum (1)
- DRIFTS (1)
- Daphnia (1)
- Daphnia longispina (1)
- Daphnia longispina complex (1)
- Daphnia longispina-Komplex (1)
- Data Mining (1)
- Data compression (1)
- Data protection (1)
- Datenkompression (1)
- Datenschutz (1)
- Decision-support (1)
- Decodierung (1)
- Deduktion (1)
- Deep Metric Learning (1)
- Demographie (1)
- Demography (1)
- Densimetric Measurement (1)
- Depth Profile (1)
- Design Science Research (1)
- Destiny (1)
- Diagnose (1)
- Diagnosekriterien (1)
- Diagnoseunterstützung (1)
- Diagnosis (1)
- Diagnosis assistance (1)
- Dichtemessung (1)
- Differentia Scanning Calorimetry (1)
- Differential scanning calorimetry (1)
- Diffuse Quellen (1)
- Digitalisation (1)
- Digitalisierung (1)
- Dimension 3 (1)
- Distributed Algorithm (1)
- Distributed Environments (1)
- Documents (1)
- Dracaena (1)
- Drahtloses Sensorsystem (1)
- Drahtloses vermachtes Netz (1)
- Drainagegräben (1)
- Dredging (1)
- Driver Assistance Systems (1)
- Düngemittel (1)
- E-Participation (1)
- East Africa (1)
- Ebener Graph (1)
- Ebullition (1)
- Economic potential (1)
- Ecosystem service (1)
- Ecotoxicity (1)
- Eddy-covariance (1)
- Edelkrebs (1)
- Einstellung (1)
- Einstellungen gegenüber bestimmten Filmeigenschaften (1)
- Ekel (1)
- Elastic net (1)
- Elektronenmikroskopie (1)
- Elevation gradient (1)
- Emission (1)
- Empirical Research (1)
- Empirical Studies (1)
- Employee Behavior (1)
- Endangerment (1)
- Endokrine Regulation (1)
- Energiefluss (1)
- Energy fluxes (1)
- Englisch (1)
- Enhanced Representation (1)
- Enterprise Architecture Framework (1)
- Entrepreneurship Education (1)
- Entrepreneurship Experience and Extra-curricular Activity (1)
- Entscheidungsunterstützung (1)
- Environmental Risk Assessment (1)
- Environmental factors (1)
- Environmental organic chemistry (1)
- Environmental psychology (1)
- Environmental samples (1)
- Epiphyten (1)
- Erzieher (1)
- Erzieherin (1)
- Evacuation modeling (1)
- Evidence-based Psychotherapy (1)
- Eye Tracking (1)
- Eyetracking (1)
- FTIR (1)
- Fahrzeug (1)
- Farnpflanzen (1)
- Fast-slow continuum (1)
- Fault Trees (1)
- Fehlerbaum (1)
- Felis catus (1)
- Felis silvestris domestica (1)
- Ferns (1)
- Feuchtgebiet (1)
- Filmbewertung (1)
- Fischgewebe (1)
- Fledermäuse (1)
- Flesch-Reading-Ease Index (1)
- Fließgewässer (1)
- Flow decomposition (1)
- Foliicolous lichens (1)
- Food (1)
- Formal Methods (1)
- Formale Methoden (1)
- Formale Ontologie (1)
- Fotoauswahl (1)
- Fractionation (1)
- Fragebeantwortung (1)
- Freeze Coring (1)
- Fremdsprachendidaktik (1)
- Fremdsprachenunterricht (1)
- Fungicides (1)
- Fungizid (1)
- Fuzzy-Logik (1)
- Fächerkanon (1)
- GDPR (1)
- GRAF1 (1)
- Galerucinae (1)
- Gamification (1)
- Gammarus fossarum (1)
- Gangart (1)
- Ganzzahlige Optimierung (1)
- Gas storage capacity (1)
- Gasblasen (1)
- GazeTheWeb (1)
- Gefrierkernverfahren (1)
- Gefrierpunktserniedrigung (1)
- Gefährdung (1)
- Gefäßanalyse (1)
- Gel effect (1)
- Gelbbauchunke (1)
- Gelände (1)
- Gemischt-ganzzahlige Optimierung (1)
- Genetic diversity (1)
- Genetics (1)
- Genetik (1)
- Genetischer Fingerabdruck (1)
- Geographic routing (1)
- Geoinformationssystem (1)
- Geometric spanner (1)
- Geowissenschaften (1)
- Gerichteter Graph (1)
- Geschlecht (1)
- Gewässerqualität (1)
- Gewässerökologie (1)
- Glasumwandlung (1)
- Glasübergang (1)
- Globale Wertschöpfungsketten (1)
- Graph (1)
- Graph theory (1)
- Graphentheorie (1)
- Graphik-Hardware (1)
- Graphische Benutzeroberfläche (1)
- Grounded Theory (1)
- Grundbedürfnis (1)
- Gruppenarbeit (1)
- Größenfraktionierung (1)
- Grünlandbewirtschaftung (1)
- Gut content analysis (1)
- Habitat loss (1)
- Habitat networks (1)
- Habitatfragmentierung (1)
- Habitatsverlust (1)
- Hard and Soft News (1)
- Hauskatze (1)
- Hedonic (1)
- Hedonisch (1)
- Herbizid (1)
- Herzrate (1)
- Hindernis (1)
- Human Disturbance (1)
- Human-Computer Interaction (1)
- Humus (1)
- Hyaluronan (1)
- Hyaluronsäure (1)
- Hydratation (1)
- Hydration (1)
- Hydrodynamics (1)
- Hydrogel (1)
- Hydrophobie (1)
- IAT (1)
- ICM (1)
- ICP-MS (1)
- IPT (1)
- IT-Security (1)
- Imitation Learning (1)
- Implicit Association Test (1)
- Industriepolitik (1)
- Information Centric Networking (1)
- Information Retrieval (1)
- Innerbetriebliche Kooperation (1)
- Insecticide (1)
- Instructed Second Language Acquisition (1)
- Integrated Model (1)
- Interaktion (1)
- Interaktionseffekt (1)
- Intergruppenprozesse (1)
- Internationale Organisationen (1)
- Interparticulate hydrogel swelling (1)
- Java (1)
- Journalismusforschung (1)
- Justification (1)
- Kalkmagerrasen (1)
- Kanalcodierung (1)
- Kantenbewerteter Graph (1)
- Kation-Brücken (1)
- Kationen (1)
- Katze (1)
- Kenya (1)
- Klassifikation (1)
- Klima (1)
- Knowledge (1)
- Knowledge Graphs (1)
- Kognitive Entwicklung (1)
- Kohlenstoffkreislauf (1)
- Kohlenstoffschichten (1)
- Kollaboration (1)
- Kollektivismus (1)
- Kolloid (1)
- Kolloide (1)
- Kolloids (1)
- Komplexität / Algorithmus (1)
- Konjugation (1)
- Konkurrenz (1)
- Konsistenz. Psychologie (1)
- Konsumentenverhalten (1)
- Konsumverzicht (1)
- Kontaktwinkel (1)
- Krebspest (1)
- Kriterium (1)
- Kryo (1)
- Körperliche Aktivität (1)
- Künstliche Intelligenz (1)
- Künstliche Neuronale Netze (1)
- L2 writers (1)
- Lake Kinneret (1)
- Lake Naivasha (1)
- Lake Wamala (1)
- Lakes (1)
- Landscape ecology (1)
- Landschaftskartierung (1)
- Landschaftsökologie (1)
- Langlebigkeit (1)
- Laser (1)
- Lasso (1)
- Last-year students (1)
- Latent Negative (1)
- Laufen (1)
- Lebenslanges Lernen (1)
- Lebensmittel (1)
- Lebensstandard (1)
- Lehrerbildung (1)
- Lehrerkompetenzen (1)
- Leichte Sprache (1)
- Leugnung (1)
- Life history (1)
- Limnologie (1)
- Limnology (1)
- Limology (1)
- Line Space (1)
- Linguistic Requirements (1)
- Link Prediction (1)
- Loans (1)
- Local algorithm (1)
- Logischer Schluss (1)
- Longevity (1)
- Lurche (1)
- Lycophytes (1)
- Magnetis (1)
- Maifisch (1)
- Makrophyten (1)
- Mapping <Mathematics> (1)
- Mass-Spektrometrie (1)
- Mathematical optimisation (1)
- Mathematik (1)
- Maßtheorie (1)
- Measure-theory (1)
- Meiofauna (1)
- Mensch-Maschine-Interaktion (1)
- Mesofauna (1)
- Metalle/Matalloide (1)
- Metalloids (1)
- Metals (1)
- Metals/metalloids (1)
- Metamodel (1)
- Metapher (1)
- Metapopulation dynamics (1)
- Metapopulationsdynamiken (1)
- Methan (1)
- Methane emissions (1)
- Methode (1)
- Microfinance (1)
- Microfinance institutions (1)
- Microplastics (1)
- Micropollutants (1)
- Mikrofinanzierung (1)
- Mikroplastik (1)
- Mikrosatelliten-DNA (1)
- Mikroverunreinigung (1)
- Minderung (1)
- Minimalschnitt (1)
- Mining (1)
- Mixed integer programming (1)
- Mixed methods (1)
- Mixture Toxicity (1)
- Monitoring (1)
- Monolepta (1)
- Mosambik (1)
- Movie evaluation criteria (1)
- Mucilage (1)
- Multiagentensysteme (1)
- Multimodal Action Recognition (1)
- Multimodal Medical Image Analysis Cochlea Spine Non-rigid Registration Segmentation ITK VTK 3D Slicer CT MRI CBCT (1)
- Multiple Object Tracking (1)
- Multivariable Statistik (1)
- NMR relaxometry (1)
- NMR-Spektroskopie (1)
- Nachbarschaftsgraph (1)
- Nachtfalter (1)
- Nachtschmetterlinge (1)
- Named Function Networking (1)
- Nanoröhren (1)
- Nassbaggerung (1)
- Nationalismus (1)
- Naturschutzgenetik (1)
- Naturschutzmanagement (1)
- Natürliche Schädlingskontrolle (1)
- Natürliches organisches Material (1)
- Near-surface turbulence (1)
- Network robustness (1)
- Networks (1)
- Netzwerk (1)
- Netzwerkrobustheit (1)
- Netzwerktopologie (1)
- Neuroactive chemicals (1)
- Nicht-Ziel-Pflanzen (1)
- Non-freezing water (1)
- Nuclear Magnetic R (1)
- Nutzererleben (1)
- Nyungwe National Park (1)
- Nährstoffverfügbarkeit (1)
- Nützlinge (1)
- OCB (1)
- OWL <Informatik> (1)
- Oberflächen-Runoff (1)
- Oberflächeneigenschaft (1)
- Oberflächenveredelung (1)
- Oligomer (1)
- One-Shot Action Recognition (1)
- Online grocery shopping (1)
- Online-Lebensmittelhandel (1)
- Ontologie <Wissensverarbeitung> (1)
- Ontology (1)
- Open Content (1)
- Open Source (1)
- Optimierung (1)
- Optimization (1)
- Organische Bodensubstanz (1)
- Oriental region (1)
- Ostafrika (1)
- Osteocephalus (1)
- Ozon (1)
- Ozonisierung (1)
- Parteienkommunikation (1)
- Passiver Wortschatz (1)
- Perfect (1)
- Perfekt (1)
- Personality (1)
- Persönlichkeit (1)
- Pestizide (1)
- Petri Nets (1)
- Petri-Netz (1)
- Pflanzen (1)
- Pharmaceuticals (1)
- Pharmakokinetik (1)
- Phosphorsäureester (1)
- Photographie (1)
- Phylogeographie (1)
- Physik (1)
- Placement Strategies (1)
- Planar graphs (1)
- Plant Communities (1)
- Plant protection products (1)
- Plastic mulching (1)
- Plasticization; Glass transition (1)
- Plastifizieren (1)
- Plastifizierung (1)
- Policy Language (1)
- Politische Ökonomie (1)
- Pollinators (1)
- Pollution (1)
- Polysaccharide (1)
- Polysaccharides (1)
- Populationsgenetik (1)
- Pore Water (1)
- Pragmatic (1)
- Pragmatisch (1)
- Predictive Model (1)
- Present Perfect (1)
- Pro-environmental behaviour change (1)
- Proactive Caching (1)
- Einbringen (1)
- Process Quality (1)
- Product choice (1)
- Produktbewertung (1)
- Produktentscheidung (1)
- Produktwahl (1)
- Propagation (1)
- Prosoziales Verhalten (1)
- Proteinstrukturanalyse (1)
- Provenance (1)
- Prozessqualität (1)
- Prädikatenlogik (1)
- Präposition (1)
- Präsentisches Perfekt (1)
- Pteris (1)
- Py-GC/MS (1)
- Pyrethroide (1)
- Pädagogik (1)
- Quasi unit disk graph (1)
- Random Finite Sets (1)
- Random Forest (1)
- Raupe (1)
- Raytracing (1)
- Reactive algorithm (1)
- Rechtfertigung (1)
- Rechtfertigung <Philosophie> (1)
- Recovery (1)
- Reference Model (1)
- Referenzrahmen (1)
- Regenwald (1)
- Regenwald ; Afrika ; Cheilolejeunea (1)
- Regionenlabeling (1)
- Rehabilitation (1)
- Religiosität (1)
- Renewable energy (1)
- Reproduktion (1)
- Reservoir Sedimentation (1)
- Reservoirs (1)
- Resource Governance (1)
- Revision (1)
- Rezeptionsforschung (1)
- Rhein (1)
- Rheinland-Pfalz (1)
- Rheometry (1)
- Rhineland-Palatinate (1)
- Rhizosphere (1)
- Right-wing ideology (1)
- Risikoabschätzung (1)
- Risikominimierung (1)
- Risk assessment (1)
- Roboter (1)
- Routing (1)
- Ruscaceae (1)
- Russia (1)
- Räuber (1)
- Rückverfolgbarkeit (1)
- SOA (1)
- SPEAR (1)
- Salinisation (1)
- Satelliten-DNS (1)
- Saving (1)
- Saving and credit cooperatives (SACCOs) (1)
- Schadstoffbelastung (1)
- Schadstoffkonzentration (1)
- Schizophrenie (1)
- Schlussfolgern (1)
- Schreiben (1)
- Schreibtechnik (1)
- Schulden (1)
- Schwebstoffe (1)
- Schwermetalle (1)
- Schädlingskontrolle (1)
- Security Requirements (1)
- Sediment Water Interface (1)
- Sediment-Water-Interfaces (1)
- See (1)
- Selbstbeobachtung (1)
- Selbstbeschädigung (1)
- Selbsteinschaetzung (1)
- Selbstregulation (1)
- Self-determination theory (1)
- Semantic Data (1)
- Semantic Web Data (1)
- Serviceorientierte Architektur (1)
- Sexuelle Orientierung (1)
- Size-fractionation (1)
- Skalenkonstruktion (1)
- Skalenvalidierung (1)
- Skalierungsmodelle (1)
- Social Cognitive Career Theory (1)
- Social Entrepreneurship in Vietnam (1)
- Social identity theory (1)
- Socio-ecological transformation (1)
- Socio-economic development (1)
- Software Language (1)
- Software Technology (1)
- Softwarearchitektur (1)
- Soil physics (1)
- Soil structural stability (1)
- Sorption (1)
- Southern Amazonia (1)
- Sozial-ökologische Transformation (1)
- Soziale Identität (1)
- Soziale Wahrnehmung (1)
- Soziales Netzwerk (1)
- Sparen (1)
- Spear (1)
- Speciation (1)
- Species turnover (1)
- Spiralcurriculum (1)
- Sprechweise (1)
- Standard of living (1)
- Staubewässerung (1)
- Staugeregelte Flüsse (1)
- Stausee (1)
- Stauseeverlandung (1)
- Stechmücke (1)
- Stechmücken-Kontrolle (1)
- Stereotyp (1)
- Stereotype Content Model (1)
- Stimme (1)
- Stimmungsveränderung (1)
- Straßenzustand (1)
- Structural Equation Modeling (1)
- Structural Validity (1)
- Strukturelle Validität (1)
- Sufficiency (1)
- Sufficiency orientation (1)
- Suffizienz (1)
- Suffizienzorientierung (1)
- Surface Science (1)
- Sustainability (1)
- Systematics (1)
- Säugetiere (1)
- Südafrika (1)
- Süßwasserhaushalt (1)
- Taxonomy (1)
- Technical potential (1)
- Technologischer Raum (1)
- Tempus (1)
- Tense (1)
- Theorembeweiser (1)
- Time (1)
- Titandioxid-Nanopartikeln (1)
- Torf (1)
- Toxicological characterization (1)
- Toxicology (1)
- Toxikologische Bewertung (1)
- Toxizität (1)
- Transfer coefficients (1)
- Transformation products (1)
- Transformationsprodukte (1)
- Tropfenform (1)
- Tropical rainforest (1)
- Tropischer Regenwald (1)
- Turbulence (1)
- Turbulenz (1)
- Type System (1)
- Type system (1)
- UML (1)
- Umkehrosmose (1)
- Umwelt (1)
- Umweltchemikalie (1)
- Umweltproben (1)
- Umwelttoxikologie (1)
- Umweltverhaltensänderung (1)
- Umweltverschmutzung (1)
- Unit disk graph (1)
- Unlink Prediction (1)
- Unsicheres Schließen (1)
- Unterrichtsforschung (1)
- Unterrichtsqualität (1)
- Untersuchung (1)
- Unterwasserwelt (1)
- User experience (1)
- VIACOBI (1)
- Variabilität (1)
- Vascular analysis (1)
- Vegetation (1)
- Verb (1)
- Verbal Aspect (1)
- Verbraucherverhalten (1)
- Vergangenheitstempus (1)
- Verhandlung (1)
- Verifikation (1)
- Vermeidung (1)
- Versalzung (1)
- Verteilter Algorithmus (1)
- Verteilung (1)
- Visual Stimuli Discovery (1)
- Visualisierung von Verbformen (1)
- Vocabulary (1)
- Vokabellernen (1)
- Volumen-Rendering (1)
- Vorschulkind (1)
- Vulnerability (1)
- WCET (1)
- Wachstumsregler (1)
- Wahlen zum europäischen Parlament (EU-Wahlen) (1)
- Wahrscheinlichkeit (1)
- Wahrscheinlichkeitsrechnung (1)
- Wanderfische (1)
- Wasser-Sediment-Grenzschichten (1)
- Wasserverschmutzung (1)
- Wastewater (1)
- Water Management (1)
- Water quality (1)
- Wavelet (1)
- Web (1)
- Web Science (1)
- Weinbau (1)
- Weltkultur (1)
- Wiederbesiedlung (1)
- Wild pollinator (1)
- Wildbienen (1)
- Wildtiere (1)
- Wirbellose (1)
- Wireless sensor network (1)
- Wirtschaft (1)
- Wirtschaftsenglisch (1)
- Wissensmanagement (1)
- World Wide Web 2.0 (1)
- Wortschatz (1)
- Yellow-bellied toad (1)
- Zeit (1)
- Zikaden (1)
- Zoologie (1)
- Zoology (1)
- Zooplankton (1)
- Zuckmücken (1)
- Zusammenhängender Graph (1)
- absolutism (1)
- acceptance (1)
- activated sludge (1)
- adaptive GUI Design (1)
- adjoint functions (1)
- advanced wastewater treatment (1)
- agricultural intensification (1)
- agroecosystems (1)
- amorphous hydrogenated carbon layer (1)
- amphibians (1)
- analytics (1)
- anthropogenic disturbance (1)
- aquatic environment (1)
- aquatic invertebrates (1)
- attitudes towards specific movie features (1)
- authoritarianism (1)
- automated theorem prover (1)
- automatic behavioral cues (1)
- bats (1)
- behavior change (1)
- behavioural ecology (1)
- belief in just world (1)
- beneficial insects (1)
- benthic oxygen fluxes (1)
- biocide (1)
- biocides (1)
- biodiversity conservation (1)
- biofiltration (1)
- bioindicator (1)
- biological degradation (1)
- biologischer Abbau (1)
- biotransformation (1)
- bioturbation (1)
- bribery (1)
- business intelligence (1)
- carbon hybridisation (1)
- cation bridges (1)
- cation-bridges (CaB) (1)
- chalk grassland (1)
- change (1)
- chemical force microscopy (1)
- chemical risk assessment (1)
- chironomids (1)
- classification (1)
- clonal diversity (1)
- cognitive development (1)
- cognitive linguistic approach (1)
- collaboration (1)
- collectivism (1)
- colloid (1)
- competition (1)
- concurrency (1)
- conflict detection (1)
- conservation genetics (1)
- construction materials (1)
- contact angle (1)
- contemporary detective fiction (1)
- cooperation (1)
- corrosion protection (1)
- corrosion resistance (1)
- covid-19 (1)
- criminal victimization (1)
- critical section (1)
- crop pollination (1)
- cross-linking (1)
- cryo-electron microscopy (1)
- cultural landscape (1)
- data mining (1)
- data protection (1)
- decision support tool (1)
- deductive (1)
- dengue (1)
- description logic (1)
- digital transformation (1)
- disabled detective (1)
- disabled masculinity (1)
- disgust sensitivity (1)
- distribution (1)
- disturbance (1)
- dry inland waters (1)
- ebullition (1)
- ecological risk management (1)
- ecology (1)
- ecosystem functioning (1)
- ecosystem services (1)
- ecotoxicity (1)
- eddy correlation (1)
- educational alliance (1)
- effect assessment (1)
- effect-directed analysis (1)
- emerging micropollutants (1)
- empirische Untersuchung (1)
- endocrine disrupting chemicals (1)
- endokrine Regulation (1)
- energetics (1)
- english prepositions (1)
- enterprise collaboration platforms (1)
- enterprise collaboration systems (1)
- environmental compatibility (1)
- environmental psychology (1)
- environmental risk assessment (1)
- environmental surfaces (1)
- epidemiology (1)
- epoxide (1)
- erweiterte Abwasserbehandlung (1)
- evolution (1)
- expansion (1)
- fairness (1)
- feedback (1)
- field experiment (1)
- field margin (1)
- fish tissues (1)
- floral resources (1)
- flows over time (1)
- fluid disturbances (1)
- focused feedback (1)
- folksonomies (1)
- framework (1)
- freshwater ecosystem (1)
- fungicide (1)
- fungus resistant grapevine (1)
- futex (1)
- gait (1)
- galvanic anodes (1)
- gender (1)
- genotyping error (1)
- giftedness (1)
- glass transition (1)
- global carbon cycle (1)
- grade (1)
- grassland irrigation (1)
- greenhouse gases (1)
- groundwater remediation (1)
- groupwork (1)
- hazard prediction (1)
- heart rate (1)
- high power impulse magnetron sputtering (1)
- humic acid (1)
- hybrid automata (1)
- hybride Automaten (1)
- hydrodynamic chromatography (1)
- hydrodynamische Chromatographie (1)
- hydrophobicity (1)
- immediate priority ceiling protocol (1)
- implicit-explicit consistency (1)
- impounded rivers (1)
- in situ (1)
- information infrastructure (1)
- information retrieval (1)
- insecticide (1)
- interaction (1)
- intergroup contact (1)
- invasive Arten (1)
- invasive species (1)
- invertebrates (1)
- kinematics (1)
- klonale Diversität (1)
- land use (1)
- land use change (1)
- landmarks (1)
- landscape (1)
- landscape complexity (1)
- landscape mapping (1)
- laser induced fluorescence (1)
- leaching (1)
- lead desorption (1)
- leaf beetles (1)
- leafhoppers (1)
- lexical sophistication (1)
- life cycle test (1)
- lifelong learning (1)
- long-living systems (1)
- longitudinal (1)
- macroinvertebrates (1)
- mammals (1)
- masculine disability (1)
- masculine identity (1)
- mathematical Modelling (1)
- mathematische Modellbildung (1)
- measure (1)
- metal-film phase plate (1)
- methane (1)
- microsatellite DNA (1)
- microsatellite analysis (1)
- minimal pruning (1)
- mitigation (1)
- mitigation measures (1)
- mixtures (1)
- modeling (1)
- monitor (1)
- mood change (1)
- multiagent systems (1)
- mutual exclusion (1)
- nanoparticle (1)
- nationalism (1)
- natural language generation (1)
- natural organic matter (1)
- nature conservation (1)
- negotiation (1)
- neuartige Spurenstoffe (1)
- nicht gefrierbares Wasser (1)
- nichtlinearer Zusammenhang (1)
- nichtsuizidale Selbstverletzung (1)
- non-consumptive effects (1)
- non-crop habitats (1)
- non-point source (1)
- non-target effects (1)
- non-target plants (1)
- nternational organizations (1)
- numerical simulation (1)
- off-field habitats (1)
- olive mill wastewater (1)
- optimization (1)
- organic coatings (1)
- organic pollution (1)
- organizational behavior (1)
- organophosphate (1)
- ozonation (1)
- ozonation of beta blockers (1)
- ozone (1)
- ozone reactivity (1)
- pH-Wert (1)
- parameter estimation (1)
- peat (1)
- pelzresistente Rebsorten (1)
- periphyton (1)
- pest control (1)
- pesticide risk assessment (1)
- pharmaceuticals (1)
- photo selection (1)
- physical activity (1)
- plain language (1)
- plant protection products (1)
- planthoppers (1)
- plants (1)
- plastic consumption (1)
- playful learning (1)
- point source (1)
- pollen diet (1)
- pollinator development (1)
- pollinator fitness (1)
- pollution (1)
- polyurethane (1)
- population genetics (1)
- predation (1)
- predictability (1)
- preschool children (1)
- priority effects (1)
- priority-Effekte (1)
- privacy by design (1)
- privacy impact assessment (1)
- probabilistic (1)
- prosocial behavior (1)
- prosoziale Gruppennorm (1)
- punishment goals (1)
- pyrethroids (1)
- question answering (1)
- rainforest (1)
- reasoning (1)
- recolonisation (1)
- region labeling (1)
- relative Prototypikalität (1)
- religiousness (1)
- repellency (1)
- reproduction (1)
- reverse osmosis (1)
- revision (1)
- rocking-phase plate (1)
- running (1)
- runoff (1)
- scaffolded writing (1)
- scale construction (1)
- scale validation (1)
- school attack (1)
- school tier (1)
- science learning (1)
- security (1)
- self-concept (1)
- semantics (1)
- sexual orientation (1)
- silver nanoparticles (1)
- single-particle analysis (1)
- social perception (1)
- software engineering (1)
- soil (1)
- soil aquifer treatment (1)
- soil pH (1)
- soil solution (1)
- soil water repellency (1)
- soils (1)
- sparsity (1)
- spatial Fuzzy Logic (1)
- spatial and temporal varibility (1)
- speech (1)
- spray-drift (1)
- stereotypes (1)
- stream (1)
- stream mesocosm (1)
- student misbehavior (1)
- student writing (1)
- surface characteristics (1)
- suspended particle matter (1)
- swarming (1)
- swimming behaviour (1)
- systematics (1)
- tag recommendation (1)
- task orientation (1)
- teacher beliefs (1)
- teacher education (1)
- teacher motivation (1)
- teacher training (1)
- teaching (1)
- text-picture integration (1)
- thermal analysis (1)
- titanium nitride (1)
- toxicokinetics (1)
- trace organic chemicals (1)
- traceability (1)
- trait-mediated effects (1)
- transformation (1)
- transformation products (1)
- trophic cascades (1)
- uptake (1)
- variational discretization (1)
- vascular plants (1)
- vaskuläre Planzen (1)
- vegetated treatment systems (1)
- verification (1)
- viticulture (1)
- voice (1)
- wastewater treatment plant (1)
- water pollution (1)
- water reuse (1)
- water scarcity (1)
- water treatment (1)
- water-molecule-bridges (WaMB) (1)
- wear resistance (1)
- web 2.0 (1)
- wettability (1)
- wild bees (1)
- wildlife management (1)
- window of opportunity (1)
- world polity (1)
- writing (1)
- zooplankton (1)
- Ästuar (1)
- Ökologie (1)
- Ökosystem (1)
- Ökotoxologie (1)
- Überarbeitung (1)
- Überwachung (1)
Institut
- Fachbereich 7 (73)
- Institut für Informatik (27)
- Institut für Integrierte Naturwissenschaften, Abt. Biologie (23)
- Fachbereich 8 (20)
- Institut für Umweltwissenschaften (19)
- Institute for Web Science and Technologies (11)
- Institut für Computervisualistik (9)
- Institut für Integrierte Naturwissenschaften, Abt. Chemie (9)
- Mathematisches Institut (8)
- Institut für Anglistik und Amerikanistik (7)
Soziale Medien bieten eine leistungsstarke Möglichkeit für Menschen, Meinungen und Gefühle zu einem bestimmten Thema auszutauschen, sodass andere von diesen Gedanken und Gefühlen profitieren können. Dieses Verfahren erzeugt eine riesige Menge an unstrukturierten Daten, wie Texte, Bilder und Verweise, die durch täglich anwachsende Kommentare zu verwandten Diskussionen ständig zunimmt. Die riesige Menge an unstrukturierten Daten stellt jedoch ein Risiko für den Prozess der Informationsextraktion dar, sodass die Entscheidungsfindung zu einer großen Herausforderung wird. Dies liegt daran, dass die Datenflut zu einem Verlust von nützlichen Daten aufgrund ihrer unangemessenen Darstellung und ihrer Anhäufung führen kann. Insofern leistet diese Arbeit einen Beitrag zum Gebiet der Sentimentanalyse und des Opinion Mining, das darauf abzielt, Emotionen und Meinungen aus riesigen Text- und Bilddatensätzen zu extrahieren. Das ultimative Ziel ist es, jeden Text oder jedes Bild als Ausdruck einer positiven, negativen oder neutralen Emotion zu klassifizieren, um bei der Entscheidungsfindung zu helfen. Sentiment- und Meinungsklassifikatoren wurden für Text- und Bilddatensätze aus sozialen Medien entwickelt, z. B. für Firmen- oder Produktbewertungen, Blogbeiträge und sogar Twitter-Nachrichten. In dieser Arbeit wird zunächst eine neue Methode zur Reduktion der Dimension von Textdaten auf Basis von Data-Mining-Ansätzen vorgestellt und anschließend das Sentiment auf Basis von neuronalen und Deep Neural Network-Klassifikationsalgorithmen untersucht. Anschließend untersuchen wir im Gegensatz zur Sentiment-Analyseforschung in Textdatensätzen die Sentiment Ausdrucks- und Polaritätsklassifikation innerhalb und über Bilddatensätze hinweg, indem wir tiefe neuronale Netze auf Basis des Aufmerksamkeitsmechanismus aufbauen.
Echzeitbetriebssysteme für Systeme mit gemischten Kritikalitäten müssen unterschiedliche Arten von Software, wie z.B. Echtzeitanwendungen und Allzweckanwendungen, gleichzeitig unterstützen. Dabei müssen sie eine solide räumliche und zeitliche Isolation zwischen unabhängigen Softwarekomponenten bieten. Daher fokussieren sich aktuelle Echtzeitbetriebssysteme hauptsächlich auf Vorhersagbarkeit und ein berechenbares Worst-Case-Verhalten.
Allerdings bieten Allzweck-Betriebssysteme wie Linux häufig effizientere, aber weniger deterministische Mechanismen, welche die durchschnittliche Ausführungszeit signifikant erhöhen. Diese Thesis befasst sich mit der Kombination der beiden gegensätzlichen Anforderungen und zeigt Mechanismen zur Thread-Synchronisation mit einem effizienten Durchschnittsverhalten, ohne jedoch die Vorhersagbarkeit und das Worst-Case-Verhalten zu beeinträchtigen. Diese Thesis untersucht und bewertet den Entwurfsraum von Abkürzungen (engl. fast paths) bei der Umsetzung von typischen blockierenden Synchronisationsmechanismen wie Mutexen, Bedingungsvariablen, Zähl-Semaphoren, Barrieren oder Nachrichtenwarteschlangen. Der Ansatz ist dabei, unnötige Systemaufrufe zu vermeiden. Systemaufrufe haben im Vergleich zu anderen Prozessoroperationen, die im Benutzermodus verfügbar sind, wie z.B. atomaren Operationen, höhere Kosten. Insbesondere erforscht die Thesis Futexe, ein aktuelles Design für blockierende Synchronisationsmechanismen in Linux, welches den konkurrenzfreien Fall der Synchronisierung mithilfe atomarer Operationen im Benutzermodus löst und den Kern nur aufruft, um Threads zu suspendieren und aufzuwecken. Die Thesis untersucht auch nicht-unterbrechbare Monitore mit aktivem Warten. Dort wird ein effizienter Mechanismus mit Prioritätsschranken verwendet, um das sogenannte Lock-Holder-Preemption-Problem ohne Systemaufrufe zu vermeiden. Ebenfalls werden passende niedere Kernprimitive beschrieben, die effiziente Warte- und Benachrichtigungsoperationen ermöglichen. Die Evaluation zeigt, dass die vorgestellten Ansätze die durchschnittliche Leistung vergleichbar zu aktuellen Ansätzen in Linux verbessern. Gleichzeitig zeigt eine Analyse des Worst-Case Zeitverhaltens, dass die Ansätze nur konstante oder begrenzte zeitliche Mehraufwände auf der Ebene des Betriebssystemkerns benötigen. Die Nutzung dieser Abkürzungen ist ein lohnender Ansatz für den Entwurf von Systemen, die nicht nur Echtzeitanforderungen erfüllen, sondern auch Allzweckanwendungen gut unterstützen sollen.
In Agrarlandschaften zählen Laufkäfer zu den weit verbreiteten Fressfeinden verschiedener Schädlinge, wie etwa von Nacktschnecken. Einflüsse von naturnahen Randstrukturen auf Laufkäfer und deren Potenzial zur natürlichen Schädlingsbekämpfung sind bekannt.
Der Einfluss von naturnahen Randstrukturen wurde auf randstrukturbewohnende Laufkäfer und Schnecken untersucht (Kapitel 2). Die Mehrzahl an Laufkäfern sowie Deroceras reticulatum präferierten Krautsäume, wohingegen Arion spp. vor allem in Gehölzen vorkam. Steigende Abundanzen von räuberischen Laufkäferarten und abnehmende Zahlen von Arion spp., gefördert durch einen hohen Anteil an Randstrukturen, lassen auf ein erhöhtes Potenzial zur Schneckenbekämpfung in strukturreichen Landschaften schließen.
Der Einfluss von naturnahen Randstrukturen wurde auf räuberische Laufkäfer und Schnecken in 18 Weizenfeldern getestet (Kapitel 3). Der Artenreichtum an karnivoren Laufkäfern stieg zusammen mit dem Anteil an Randstrukturen in der Landschaft, wobei deren Abundanz von kleinräumigen Effekten unbeeinflusst blieb. Die beiden Schädlinge zeigten unterschiedliche Muster, wobei Dichten von Arion spp. an Gehölzen in strukturarmen Landschaften am höchsten waren. D. reticulatum wurde weder durch lokale noch von großräumigen Effekten beeinflusst, was auf ihre Anpassung an Agrarlandschaften zurückzuführen ist. Die Ergebnisse lassen auf eine gesteigerte Kontrolle von Arion spp. durch Laufkäfer in strukturreichen Gebieten schließen.
Effekte von Randstrukturen und Bewirtschaftung wurden auf die Verteilung von Laufkäfern in 18 Kürbisfeldern getestet (Kapitel 4). Der Artenreichtum stieg mit Nähe zu den Randstrukturen, wobei Laufkäferabundanzen je nach Habitattyp unterschiedlich beeinflusst wurden. Die Bewirtschaftungsart hatte keinen Einfluss auf Laufkäfer und Landschaftsheterogenität beeinflusste nur Laufkäfer in ökologisch bewirtschafteten Feldern.
Prädationsexperimente von Schnecken und deren Eiern durch drei Laufkäferarten wurden im Labor in Einzel- und Zweierkonstellationen durchgeführt (Kapitel 5). Je nach Art wurden synergistische und additive Effekte gemessen. Generell erhöhen naturnahe Randstrukturen das Potenzial zur Schneckenbekämpfung durch Laufkäfer, was vor allem für Schnecken der Gattung Arion zählt. Es ist wichtig, einen bestimmten Anteil an naturnahen Randstrukturen in Agrarlandschaften bereitzustellen, da sie als Rückzugs-, Eiablage- und Überwinterungsorte fungieren und komplementäre Nahrungsressourcen bereitstellen.
The global problematic issue of the olive oil industry is in its generation of large amounts of olive mill wastewater (OMW). The direct discharge of OMW to the soil is very common which presents environmental problems for olive oil producing countries. Both, positive as well as negative effects on soil have been found in earlier studies. Therefore, the current study hypothesized that whether beneficial effects or negative effects dominate depends on the prevailing conditions before and after OMW discharge to soil. As such, a better understanding of the OMW-soil interaction mechanisms becomes essential for sustainable safe disposal of OMW on soil and sustainable soil quality.
A field experiment was carried out in an olive orchard in Palestine, over a period of 24 months, in which the OMW was applied to the soil as a single application of 14 L m-2 under four different environmental conditions: in winter (WI), spring (SP), and summer with and without irrigation (SUmoist and SUdry). The current study investigated the effects of seasonal conditions on the olive mill wastewater (OMW) soil interaction in the short-term and the long-term. The degree and persistence of soil salinization, acidification, accumulation of phenolic compounds and soil water repellency were investigated as a function of soil depth and time elapsed after the OMW application. Moreover, the OMW impacts on soil organic matter SOM quality and quantity, total organic carbon (SOC), water-extractable soil organic carbon (DOC), as well as specific ultraviolet absorbance analysis (SUVA254) were also investigated for each seasonal application in order to assess the degree of OMW-OM decomposition or accumulation in soil, and therefore, the persisting effects of OMW disposal to soil.
The results of the current study demonstrate that the degree and persistence of relevant effects due to OMW application on soil varied significantly between the different seasonal OMW applications both in the short-term and the long-term. The negative effects of the potentially hazardous OMW residuals in the soil were highly dependent on the dominant transport mechanisms and transformation mechanisms, triggered by the ambient soil moisture and temperature which either intensified or diminished negative effects of OMW in the soil during and after the application season. The negative effects of OMW disposal to the soil decreased by increasing the retention time of OMW in soil under conditions favoring biological activity. The moderate conditions of soil moisture and temperature allowed for a considerable amount of applied OMW to be biologically degraded, while the prolonged application time under dry conditions and high temperature resulted in a less degradable organic fraction of the OMW, causing the OMW constituents to accumulate and polymerize without being degraded. Further, the rainfall during winter season diminished negative effects of OMW in the soil; therefore, the risk of groundwater contamination by non-degraded constituents of OMW can be highly probable during the winter season.
Agricultural land-use may lead to brief pulse exposures of pesticides in edge-of-field streams, potentially resulting in adverse effects on aquatic macrophytes, invertebrates and ecosystem functions. The higher tier risk assessment is mainly based on pond mesocosms which are not designed to mimic stream-typical conditions. Relatively little is known on exposure and effect assessment using stream mesocosms.
Thus the present thesis evaluates the appliacability of the stream mesocosms to mimic stream-typical pulse exposures, to assess resulting effects on flora and fauna and to evaluate aquatic-terrestrial food web coupling. The first objective was to mimic stream-typical pulse exposure scenarios with different durations (≤ 1 to ≥ 24 hours). These exposure scenarios established using a fluorescence tracer were the methodological basis for the effect assessment of an herbicide and an insecticide. In order to evaluate the applicability of stream mesocosms for regulatory purposes, the second objective was to assess effects on two aquatic macrophytes following a 24-h pulse exposure with the herbicide iofensulfuron-sodium (1, 3, 10 and 30 µg/L; n = 3). Growth inhibition of up to 66 and 45% was observed for the total shoot length of Myriophyllum spicatum and Elodea canadensis, respectively. Recovery of this endpoint could be demonstrated within 42 days for both macrophytes. The third objective was to assess effects on structural and functional endpoints following a 6-h pulse exposure of the pyrethroid ether etofenprox (0.05, 0.5 and 5 µg/L; n = 4). The most sensitive structural (abundance of Cloeon simile) and functional (feeding rates of Asellus aquaticus) endpoint revealed significant effects at 0.05 µg/L etofenprox. This concentration was below field-measured etofenprox concentrations and thus suggests that pulse exposures adversely affect invertebrate populations and ecosystem functions in streams. Such pollutions of streams may also result in decreased emergence of aquatic insects and potentially lead to an insect-mediated transfer of pollutants to adjacent food webs. Test systems capable to assess aquatic-terrestrial effects are not yet integrated in mesocosm approaches but might be of interest for substances with bioaccumulation potential. Here, the fourth part provides an aquatic-terrestrial model ecosystem capable to assess cross-ecosystem effects. Information on the riparian food web such as the contribution of aquatic (up to 71%) and terrestrial (up to 29%) insect prey to the diet of the riparian spider Tetragnatha extensa was assessed via stable isotope ratios (δ13C and δ15N). Thus, the present thesis provides the methodological basis to assess aquatic-terrestrial pollutant transfer and effects on the riparian food web.
Overall the results of this thesis indicate, that stream mesocosms can be used to mimic stream-typical pulse exposures of pesticides, to assess resulting effects on macrophytes and invertebrates within prospective environmental risk assessment (ERA) and to evaluate changes in riparian food webs.
Systemische Neonicotinoide gehören zu den weltweit meist genutzten Insektiziden. Neben ihrer Anwendung in der Landwirtschaft werden sie zunehmend zur Bekämpfung von Baumschädlingen in
der Forstwirtschaft eingesetzt. Die im Herbst von Laubbäumen fallenden Blätter können allerdings
immer noch Neonicotinoide enthalten. Gelangen diese kontaminierten Blätter schließlich in
nahegelegene Bäche werden die wasserlöslichen Neonicotinoide wieder mobilisiert und somit
potenziell aquatische Nicht-Zielorganismen über die Wasserphase exponiert. Obwohl der Standardtestorganismus Daphnia magna (Crustacea; Cladocera) relativ unempfindlich gegenüber
Neonicotinoiden ist, sind viele andere aquatische Invertebraten bereits bei einer Exposition im ng/L- bis niedrigem μg/L-Bereich negativ beeinträchtigt. Besonders laubzersetzende Invertebraten (= Shredder) könnten, zusätzlich zu einer Exposition über die Wasserphase, durch den Eintrag von Neonicotinoid-kontaminiertem Laub in ein Fließgewässer negativ beeinträchtigt werden, da Laub für sie eine essentielle Nahrungsquelle darstellt. Jedoch erhielt dieser Expositionspfad im Zusammenhang mit aquatischen Shreddern und Neonicotinoid-kontaminiertem Pflanzenmaterial bisher kaum Aufmerksamkeit seitens der Forschung und findet keine Berücksichtigung in der aquatischen Umweltrisikobewertung. Das Hauptziel dieser Arbeit war daher (1) Neonicotinoidrückstände in Blättern zu quantifizieren sowie für Shredder relevante Expositionswege zu identifizieren, (2)
ökotoxikologische Effekte einer Exposition über die Wasserphase sowie über die Nahrung für zwei
Modell-Shredder Gammarus fossarum (Amphipoda) und Chaetopteryx villosa (Insecta) zu untersuchen, und schließlich (3) biotische und abiotische Faktoren zu betrachten, welche eine Exposition unter Feldbedingungen potenziell beeinträchtigen könnten.
Im Rahmen dieser Arbeit konnten Rückstände der Neonicotinoide Imidacloprid, Thiacloprid und
Acetamiprid in Blätter behandelter Schwarzerlen quantifiziert werden. Ein entwickeltes „Worst-Case
Modell“ prognostizierte niedrige Imidaclopridwasserkonzentrationen für einen Bach in welchen Imidacloprid-kontaminierte Blätter eingetragen werden. Jedoch konnte mit Hilfe des Modells die Aufnahme über die Nahrung als ein für aquatische Shredder relevanter Expositionspfad identifiziert werden. Der Konsum von Neonicotinoid-kontaminierten Blättern führte, bei gleichzeitiger Exposition über die Wasserphase (= kombinierte Exposition), in beiden Testorganismen zu stärkeren Effekten als die alleinige Exposition über die Wasserphase. Des Weiteren gelang es in einem weiteren Laborexperiment die beiden Expositionswege mittels einer Durchflussanlage zu separieren. Hierbei führte die separate Exposition von G. fossarum sowohl über die Nahrung (= Konsum von Thiaclopridkontaminierten Blättern) als auch über die Wasserphase zu vergleichbaren Effektgrößen. Zudem ließen sich die unter einer kombinierten Exposition beobachteten Effektgrößen weitestgehend mit dem Referenzmodell der „Unabhängigen Wirkung“ vorhersagen, was eine Wirkung auf unterschiedliche molekulare Zielorte vermuten lässt. Die durch Imidacloprid ausgelöste toxischen Effekte auf G. fossarum konnten schließlich durch eine Behandlung der Blätter mit UV-Strahlung (repräsentativ für Sonnenlicht) sowie durch Leaching in Wasser reduziert werden. Jedoch waren beide Shredder-Spezies nicht dazu in der Lage aktiv eine Aufnahme von Neonicotinoiden über die Nahrung zu vermeiden. Daher geht aus dieser Arbeit die Empfehlung hervor, bereits während der Registrierung von systemischen Pestiziden, auf nahrungsbedingte Effekte zu testen und dadurch aquatische Shredder als auch assoziierte Ökosystemfunktionen (z.B. Laubabbau) zu schützen.
The intention of this thesis was to characterise the effect of naturally occurring multivalent cations like Calcium and Aluminium on the structure of Soil Organic Matter (SOM) as well as on the sorption behaviour of SOM for heavy metals such as lead.
The first part of this thesis describes the results of experiments in which the Al and Ca cation content was changed for various samples originated from soils and peats of different regions in Germany. The second part focusses on SOM-metal cation precipitates to study rigidity in dependence of the cation content. In the third part the effects of various cation contents in SOM on the binding strength of Pb cations were characterised by using a cation exchange resin as desorption method.
It was found for soil and peat samples as well as precipitates that matrix rigidity was affected by both type and content of cation. The influence of Ca on rigidity was less pronounced than the influence of Al and of Pb used in the precipitation experiments. For each sample one cation content was identified where matrix rigidity was most pronounced. This specific cation content is below the cation saturation as expected by cation exchange capacity. These findings resulted in a model describing the relation between cation type, content and the degree of networking in SOM. For all treated soil and precipitate samples a step transition like glass transition was observed, determined by the step transition temperature T*. It is known from literature that this type of step transition is due to bridges between water molecules and organic functional groups in SOM. In contrast to the glass transition temperature this thermal event is slowly reversing after days or weeks depending on the re-conformation of the water molecules. Therefore, changes of T* with different cation compositions in the samples are explained by the formation of water-molecule-cation bridges between SOM-functional groups. No influence on desorption kinetics of lead for different cation compositions in soil samples was observed. Therefore it can be assumed that the observed changes of matrix rigidity are highly reversible by changing the water status, pH or putting agitation energy by shaking in there.
The ongoing loss of species is a global threat to biodiversity, affecting ecosystems worldwide. This also concerns arthropods such as insects and spiders, which are especially endangered in agricultural ecosystems. Here, one of the main causing factors is management intensification. In areas with a high proportion of traditionally managed grassland, extensive hay meadows that are cut only once per year can still hold high levels of biodiversity, but are threatened by conversion into highly productive silage grassland. The Westerwald mountain range, western Germany, is such a region. In this thesis, I compare the local diversity of bees, beetles, hoverflies, leafhoppers, and spiders of five grassland management regimes along a gradient of land-use intensity. These comprise naturally occurring grassland fallows, three types of traditionally managed hay meadows, and intensively used silage grassland. By using three different sampling methods, I recorded ground-dwelling, flower-visiting, and vegetation-dwelling species. The results show that in most cases species richness and diversity are highest on fallows, whereas variation among different managed grassland types is very low. Also, for most sampled taxa, fallows harbour the most distinct species assemblages, while that of other management regimes are largely overlapping. Management has the largest effect on species composition, whereas environmental parameters are of minor importance. Long-term grassland fallows seem to be highly valuable for arthropod conservation, even in a landscape with a low overall land-use intensity, providing structural heterogeneity. In conclusion, such fallows should be subsidized agri-environmental schemes, to preserve insect and spider diversity.
Agriculture covers one third of the world land area and has become a major source of water pollution due to its heavy reliance on chemical inputs, namely fertilisers and pesticides. Several thousands of tonnes of these chemicals are applied worldwide annually and partly reach freshwaters. Despite their widespread use and relatively unspecific modes of action, fungicides are the least studied group of pesticides. It remains unclear whether the taxonomic groups used in pesticide risk assessment are protective for non-target freshwater fungi. Fungi and bacteria are the main microbial decomposers converting allochthonous organic matter (litter) into a more nutritious food resource for leaf-shredding macroinvertebrates. This process of litter decomposition (LD) is central for aquatic ecosystem because it fuels local and downstream food webs with energy and nutrients. Effects of fungicides on decomposer communities and LD have been mainly analysed under laboratory conditions with limited representation of the multiple factors that may moderate effects in the field.
In this thesis a field study was conducted in a German vineyard area to characterise recurrent episodic exposure to fungicides in agricultural streams (chapter 2) and its effects on decomposer communities and LD (chapter 3). Additionally, potential interaction effects of nutrient enrichment and fungicides on decomposer communities and LD were analysed in a mesocosm experiment (chapter 4).
In the field study event-driven water sampling (EDS) and passive sampling with EmporeTM styrene-divinylbenzene reverse phase sulfonated disks (SDB disks) were used to assess exposure to 15 fungicides and 4 insecticides. A total of 17 streams were monitored during 4 rainfall events within the local application period of fungicides in 2012. EDS exceeded the time-weighted average concentrations provided by the SDB disks by a factor of 3, though high variability among compounds was observed. Most compounds were detected in more than half of the sites and mean and maximum peak (EDS) concentrations were under 1 and 3 µg/l, respectively. Besides, SDB disk-sampling rates and a free-software solution to derive sampling rates under time-variable exposure were provided.
Several biotic endpoints related to decomposers and LD were measured in the same sampling sites as the fungicide monitoring, coinciding with the major litter input period. Our results suggest that polar organic fungicides in streams change the structure of the fungal community. Causality of this finding was supported by a subsequent microcosm experiment. Whether other effects observed in the field study, such as reduced fungal biomass, increased bacterial density or reduced microbial LD can be attributed to fungicides remains speculative and requires further investigation. By contrast, neither the invertebrate LD nor in-situ measured gammarid feeding rates correlated with water-borne fungicide toxicity, but both were negatively associated with sediment copper concentrations. The mesocosm experiment showed that fungicides and nutrients affect microbial decomposers differently and that they can alter community structure, though longer experiments are needed to determine whether these changes may propagate to invertebrate communities and LD. Overall, further studies should include representative field surveys in terms of fungicide pollution and physical, chemical and biological conditions. This should be combined with experiments under controlled conditions to test for the causality of field observations.
Rivers play an important role in the global water cycle, support biodiversity and ecological integrity. However, river flow and thermal regimes are heavily altered in dammed rivers. These impacts are being exacerbated and become more apparent in rivers fragmented by multiple dams. Recent studies mainly focused on evaluating the cumulative impact of cascade reservoirs on flow or thermal regimes, but the role of upstream reservoirs in shaping the hydrology and hydrodynamics of downstream reservoirs remains poorly understood. To improve the understanding of the hydrodynamics in cascade reservoirs, long-term observational data are used in combination with numerical modeling to investigate the changes in flow and thermal regime in three cascade reservoirs at the upper reach of the Yangtze River. The three studied reservoirs are Xiluodu (XLD), Xiangjiaba (XJB) and Three Gorges Reservoir (TGR). In addition, the effects of single reservoir operation (at seasonal/daily time scale) on hydrodynamics are examined in a large tributary of TGR. The results show that the inflow of TGR has been substantially altered by the two upstream reservoirs with a higher discharge in spring and winter and a reduced peak flow in summer. XJB had no obvious contribution to the variations in inflow of TGR. The seasonal water temperature of TGR was also widely affected by the upstream two reservoirs, i.e., an increase in winter and decrease in spring, associated with a delay in water temperature rise and fall. These effects will probably be intensified in the coming years due to the construction of new reservoirs. The study also underlines the importance of reservoir operation in shaping the hydrodynamics of TGR. The seasonal dynamics of density currents in a tributary bay of TGR are closely related to seasonal reservoir operations. In addition, high-frequency water level fluctuations and flow velocity variations were observed in response to periodic tributary bay oscillations, which are driven by the diurnal discharge variations caused by the operation of TGR. As another consequence of operation of cascade reservoirs, the changes in TGR inflow weakened spring thermal stratification and caused warming in spring, autumn and winter. In response to this change, the intrusions from TGR occurred more frequently as overflow and earlier in spring, which caused a sharp reduction in biomass and frequency of phytoplankton blooms in tributary bays of TGR. This study suggests that high-frequency bay oscillations can potentially be used as an efficient management strategy for controlling algal blooms, which can be included in future multi-objective ecological conservation strategies.