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Pollen and environmental reconstruction, Holocene dynamics of tropical rainforest, climate, fire, human impact and land use in Sulawesi and Sumatra, Indonesia

The present-day configuration of Indonesia and SE Asia is the results of a long history of tectonic movements, volcanisms and global eustatic sea-level changes. Not indifferent to these dynamics, fauna and flora have been evolving and dispersing following a complicate pattern of continent-sea changes to form what are today defined as Sundaland and Wallacea biogeographical regions. The modern intraannual climate of Indonesia is generally described as tropical, seasonally wet with seasonal reversals of prevailing low-level winds (Asian-Australian monsoon). However at the interannual scale a range of influences operating over varying time scales affect the local climate in respect of temporal and spatial distribution of rainfall. Vegetation generally reflects climate and to simplify it is possible to distinguish three main ecological elements in the flora of Malaysia: everwet tropical, seasonally dry tropical (monsoon) and montane. Within those major ecological groups, a wide range of specific local conditions caused a complex biogeography which has and still attract the attention of botanists and biogeographers worldwide. Being one of the richest regions in the Worlds in terms of species endemism and biodiversity, Indonesia has recently gone through intensive transformation of previously rural/natural lands for intensive agriculture (oil palm, rubber, cocoa plantations and rice fields). Climate change represents an additional stress. Projected climate changes in the region include strengthening of monsoon circulation and increase in the frequency and magnitude of extreme rainfall and drought events. The ecological consequences of these scenarios are hard to predict. Within the context of sustainable management of conservation areas and agro-landscapes, Holocene palaeoecological and palynological studies provide a valuable contribution by showing how the natural vegetation present at the location has changed as a consequence of climate variability in the long-term (e.g. the Mid-Holocene moisture maximum, the modern ENSO onset, Little Ice Age etc.). The final aim of my PhD research is to compare the Holocene history of Jambi province and Central Sulawesi. In particular: - Reconstructing past vegetation, plant diversity and climate dynamics in the two study areas Jambi (Sumatra) and Lore Lindu National Park (Sulawesi) - Comparing the ecological responses of lowland monsoon swampy rainforest (Sumatra) and everwet montane rainforests (Sulawesi) to environmental variability (vulnerability/resilience) - Investigating the history of human impact on the landscape (shifting cultivation, slash and burn, crop cultivation, rubber and palm oil plantation) - Assessing the impact and role of droughts (El Niño) and fires - Adding a historical perspective to the evaluation of current and future changes.

Schwerpunktprogramm (SPP) 1158: Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten, Biological soil crust algae in the polar regions - biodiversity, genetic diversity and ecosystem resilience under global change scenarios

Terrestrial green algae and cyanobacteria are typical and abundant components of biological soil crusts in the Polar Regions. These communities form water-stable aggregates that have important ecological roles in primary production, nitrogen fixation, nutrient cycling, water retention and stabilization of soils. Although available data on green algae and cyanobacteria are generally very limited for the Arctic and Antarctica, their functional importance as ecosystem developers in nutrient poor environments is regarded as high. Therefore, the main goal of the interdisciplinary project is, for the first time, a precise evaluation of their 1.) Biodiversity as well as of 2.) The infra-specific genetic diversity, 3.) ecophysiological performance and 4.) transcriptomics of the most abundant taxa in biological soil crusts isolated from the Antarctic Peninsula and Arctic Svalbard. Biodiversity will be investigated using a classical culture approach in combination with molecular-taxonomical methods as well as with metagenomics. The infra-specific genetic diversity of the most abundant green algae and cyanobacteria will be studied using fingerprinting techniques, and a range of selected populations characterized in relation to their physiological plasticity. Temperature and water availability, two key environmental factors for terrestrial organisms, are currently changing in Polar Regions due to global warming, and hence their effect on growth and photosynthesis response patterns will be comparatively investigated. The data will indicate whether and how global change influence population structure and ecological performance of key organisms in polar soil crusts, and help to make predictions on the future significance of the ecological functions of these pioneer communities. Such a multiphasic approach has never been applied before to soil algae and cyanobacteria in both Polar Regions, and hence represents one of the key innovations of this proposal.

Eine systematische Übersicht über Fragebögen aus Lärmwirkungsstudien

In Fragebogen-Untersuchungen zur Lärmwirkung wurden bisher sehr unterschiedliche Operationalisierungen von Wirkungsvariablen (wie z.B. Belästigung, Störung von Aktivitäten) und außer-akustischen Faktoren (sog. Moderatoren wie z.B. Lärmempfindlichkeit, misfeasance) verwendet. Deshalb hat sich die Arbeitsgruppe community response der International Commission on the Biological Effects of Noise (ICBEN, Team No. 6) als langfristiges Ziel die Entwicklung von Fragebogen-Guidelines und die Formulierung eines Muster-Fragebogens für die Lärmwirkungsforschung gesetzt. D.h. es soll ein Vorschlag erarbeitet werden, in welcher Form globale und spezifische Lärmwirkungen in Befragungen erhoben werden sollten. Um dieses Vorhaben zu unterstützen, hat der Arbeitskreis Ökologische Lärmforschung die Erstellung einer systematischen Übersicht über vorhandene Fragebögen aus Lärmwirkungsstudien auf internationaler Ebene in Angriff genommen. Diese Übersicht soll es u.a. ermöglichen, die Struktur von verschiedenen Fragebögen sowie die in ihnen verwendeten Operationalisierungen für Lärmwirkungs- und Moderatorvariablen (hinsichtlich Art der Frageformulierung sowie der Antwortformate) zu vergleichen. Für den/die einzelne/n Lärmforscher/in bietet diese Übersicht die Möglichkeit, sich auf sehr effiziente Art und Weise darüber zu informieren, wie bestimmte Konstrukte in bisherigen Untersuchungen operationalisiert worden sind bzw. welche Alternativen zu den bereits selbst angewandten Operationalisierungen bestehen. Nach einer systematischen Ermittlung von Namen und Adressen einschlägiger Lärmforscher/innen, wurden diese um die Zusendung von Fragebögen sowie ergänzender Materialien aus eigenen Lärmwirkungsstudien gebeten. Die zugesandten Fragebögen werden gegebenenfalls übersetzt und mit der Methode der qualitativen Inhaltsanalyse ausgewertet. Hierbei werden die Fragebögen im Hinblick auf formelle Aspekte (z.B. Jahr der Erhebung, Sprache, Art der Befragungsmethode) wie auch im Hinblick auf strukturelle Aspekte (z.B. Umfang des Fragebogens, abgefragte Variablengruppen, Antwortformate) ausgewertet. Hauptgegenstand der Auswertung ist aber insbesondere die Auswertung der Lärmwirkungsvariablen (z.B. die Abfrage der globalen Lärmbelästigung, Aktivitätenstörungen, Kommunikationsstörungen) sowie der Moderatorvariablen (z.B. Lärmempfindlichkeit, Lärmbewältigungsvermögen, misfeasance). Parallel dazu wurde eine Datenbank entwickelt, in der die Ergebnisse der Analysen dargestellt und verwaltet werden. Diese Datenbank wird ab November 2001 im Internet unter http://www.eco.psy.ruhr-uni-bochum.de/nqd für jede/n interessierte/n Forscher/in zugänglich und nutzbar sein. Langfristig ist darüber hinaus geplant, ein Archiv mit den Original-Fragebögen aufzubauen, in dem einzelne Fragebögen auf Wunsch eingesehen werden können.

CFK-Recycling in der Kompetenzregion Augsburg

The increasing proportion of carbon fibre reinforced plastics (CFRP) in different branches of industry will result in an increasingly larger quantity of CFRP wastes in future. With regard to improved management of natural resources, it is necessary to add these fibres that require energy-intensive production to effective recycling management. But high-quality material recycling is only ecoefficient if the recycled fibres can be used to produce new high-quality and marketable products. Tests carried out up to now indicate that very good results can be expected for large-scale recycling of carbon fibres by means of pyrolysis. The waste pyrolysis plant (WPP) operated in Burgau is the only large-scale pyrolysis plant for municipal wastes in Germany. Use of this plant to treat CFRP wastes represents a unique opportunity for the whole Southern German economy and in particular the Augsburg economic region. In a study funded by the Bavarian State Ministry of the Environment and Health ('Bayerisches Staatsministerium für Umwelt und Gesundheit'), the specific implementation options for the recovery of carbon fibres from composites by means of large-scale pyrolysis have been under investigation since November 2010. To this end, in the first step a development study was carried out, which in particular examined the options for modifying the Burgau WPP for the recycling of CFRP. The knowledge acquired from the pyrolysis tests, the fibre tests and the economic feasibility study confirmed the positive assessment of the overall concept of CFRP recycling in Burgau. As an overall result, unlimited profitability was found for all scenarios with regard to investments in CFRP recycling in Burgau WPP. The work on the development study was carried out by bifa Umweltinstitut GmbH together with the Augsburg-based 'function integrated lightweight construction project group ('Funktionsintegrierter Leichtbau' - FIL) of the Fraunhofer Institute for Chemical Technology (ICT). Methods: analysis and moderation of social processes, economy and management consulting, process engineering

Vertical partitioning and sources of CO2 production and effects of temperature, oxygen and root location within the soil profile on C turnover

For surface soils, the mechanisms controlling soil organic C turnover have been thoroughly investigated. The database on subsoil C dynamics, however, is scarce, although greater than 50 percent of SOC stocks are stored in deeper soil horizons. The transfer of results obtained from surface soil studies to deeper soil horizons is limited, because soil organic matter (SOM) in deeper soil layers is exposed to contrasting environmental conditions (e.g. more constant temperature and moisture regime, higher CO2 and lower O2 concentrations, increasing N and P limitation to C mineralization with soil depth) and differs in composition compared to SOM of the surface layer, which in turn entails differences in its decomposition. For a quantitative analysis of subsoil SOC dynamics, it is necessary to trace the origins of the soil organic compounds and the pathways of their transformations. Since SOM is composed of various C pools which turn over on different time scales, from hours to millennia, bulk measurements do not reflect the response of specific pools to both transient and long-term change and may significantly underestimate CO2 fluxes. More detailed information can be gained from the fractionation of subsoil SOM into different functional pools in combination with the use of stable and radioactive isotopes. Additionally, soil-respired CO2 isotopic signatures can be used to understand the role of environmental factors on the rate of SOM decomposition and the magnitude and source of CO2 fluxes. The aims of this study are to (i) determine CO2 production and subsoil C mineralization in situ, (ii) investigate the vertical distribution and origin of CO2 in the soil profile using 14CO2 and 13CO2 analyses in the Grinderwald, and to (iii) determine the effect of environmental controls (temperature, oxygen) on subsoil C turnover. We hypothesize that in-situ CO2 production in subsoils is mainly controlled by root distribution and activity and that CO2 produced in deeper soil depth derives to a large part from the mineralization of fresh root derived C inputs. Further, we hypothesize that a large part of the subsoil C is potentially degradable, but is mineralized slower compared with the surface soil due to possible temperature or oxygen limitation.

Leistungsoptimierte Lithium-lonen Batterien

Der schnelle Fortschritt der elektronischen Geräte erhöht die Nachfrage nach verbesserten Li-Ionen Batterien. Kommerziell erhältliche Li-Zellen nutzen meist Lithiumkobaltoxid für die positive Elektrode. Doch gerade dieses Material ist ein Hindernis für eine weitere Optimierung, insbesondere für eine Kostensenkung. Vor allem für größere Anwendungen wie Hybrid- oder Elektrofahrzeuge müssen alternative Materialen erforscht werden, die billiger, sicherer und umweltverträglicher sind. Daher wird im ISEA derzeit ein neues Forschungsprojekt ins Leben gerufen und die dafür benötigte Infrastruktur geschaffen. Die Forschung wird sich auf die Untersuchung geeigneter Übergangsmetalloxide und Polyanionen konzentrieren, die besonders gut zur Einlagerung von Li-Ionen geeignet sind. Es werden neue Herstellungsverfahren unter Verwendung wässriger Precurser-Substanzen untersucht, die Verbindungen mit überlegenen Eigenschaften erzeugen und außerdem leicht an eine Massenproduktion angepasst werden können. Ziel der Arbeiten ist, preisgünstiges Elektrodenmaterial zu entwickeln, das eine spezifische Energie von über 200 Wh/kg und eine Leistungsdichte von 400 W/kg aufweist. Außerdem werden Arbeiten im Bereich der physikalisch-chemischen Charakterisierung der neuen Materialien stattfinden sowie elektrochemische Analysen der gesamten Zellen- und Batteriesysteme durchgeführt. Das elektrodynamische Verhalten der neuen Zellen wird u. a. mit Hilfe der elektrochemischen Impedanzspektroskopie analysiert, um präzise und zuverlässige Algorithmen für ein späteres Batteriemonitoring im realen Betrieb zu finden.

Schwerpunktprogramm (SPP) 1315: Biogeochemische Grenzflächen in Böden; Biogeochemical Interfaces in Soil, Importance of soil organic carbon and mineral particle size fractions for the fate of soil supplied organic chemicals and their microbial transformations

The biogeochemical interface (BGI) in this project is defined as the organo-mineral surface of soil particles colonized by microorganisms. In the preceding project it was demonstrated that the different soil particle size fractions were associated with specifically structured microbial communities, a characteristic amount of soil organic carbon, and a specific capacity for adsorption of the organic chemicals phenol and 2,4-dichlorophenol, respectively. While the diversity of the microbial community was responsive to fertilization-determined additional organic soil carbon in the larger particle size fractions, it was unaffected in clay. Stable isotope probing with 13C-labelled phenol and 2,4-dichlorophenol revealed that the soil organic carbon in the BGIs also affected the diversity of microorganisms involved in the degradation of these chemicals. All these results are yet only based on studying one soil with three organic carbon variants (Bad Lauchstädt) and only two organic compounds. The objective of this 2nd phase project is to apply the innovative technology developed in the 1st phase for studying the BGI processes with soil organic carbon variants from another soil (Ultuna, SPP 1315 site) and with the chiralic anilide Fungicide metalaxyl as an additional compound. This 2nd phase SPP 1315 project will also, in a collaborative effort with two other SPP 1315 partners, investigate (1) the importance of BGIs for the entantio-selective degradation of metalaxyl and (2) the role of soil microorganisms in the formation of bound residues, respectively. Furthermore, the project will utilize stable isotope probing and next-generation DNA sequencing to link the structural and functional diversity of the microbial communities responsible for metabolism of organic chemicals in the different BGIs determined by particle size fractions and soil organic carbon variants.

Wie prägen kohärente Luftströmungen den Einfluss des Golfstroms auf die großskalige atmosphärische Zirkulation der mittleren Breiten?

Über dem Nordatlantik und Europa wird die Variabilität der großräumigen Wetterbedingungen von quasistationären, langandauernden und immer wiederkehrenden Strömungsmustern â€Ì sogenannten Wetterregimen â€Ì geprägt. Diese zeichnen sich durch das Auftreten von Hoch- und Tiefdruckgebieten in bestimmten Regionen aus. Verlässliche Wettervorhersagen auf Zeitskalen von einigen Tagen bis zu einigen Monaten im Voraus hängen von einer korrekten Darstellung der Lebenszyklen dieser Strömungsregime in Computermodellen ab. Um das zu erreichen müssen insbesondere Prozesse, die günstige Bedingungen zur Intensivierung von Tiefdruckgebieten aufrecht erhalten, und Prozesse, die den Aufbau von stationären Hochdruckgebieten (blockierende Hochs) begünstigen, richtig wiedergegeben werden. Aktuelle Forschung deutet stark darauf hin, dass Atmosphäre-Ozean Wechselwirkungen, insbesondere entlang des Golfstroms, latente Wärmefreisetzung in Tiefs, und Kaltluftausbrüche aus der Arktis dabei eine entscheidende Rolle spielen. Dennoch mangelt es an grundlegendem Verständnis wie solche Luftmassentransformationen über dem Ozean die großskalige Höhenströmung beeinflussen. Darüber hinaus ist die Relevanz solcher Prozesse für Lebenszyklen von Wetterregimen unerforscht. In dieser anspruchsvollen drei-jährigen Kollaboration zwischen KIT und ETH Zürich streben wir an ein ganzheitliches Verständnis zu entwickeln, wie Wärmeaustausch zwischen Ozean und Atmosphäre und diabatische Prozesse in der Golfstromregion die Variabilität der großräumigen Strömung über dem Nordatlantik und Europa prägen. Zu diesem Zweck werden wir ausgefeilte Diagnostiken zur Charakterisierung von Luftmassen mit neuartigen Diagnostiken zur Bestimmung des atmosphärischen Energiehaushaltes verbinden und damit den Ablauf von Wetterregimen und Regimewechseln in aktuellen hochaufgelösten numerischen Modelldatensätzen und mit Hilfe von eigenen Sensitivitätsstudien untersuchen. Dazu werden wir unsere Expertise in größräumiger Dynamik und Wettersystemen, sowie Atmosphäre-Ozean Wechselwirkungen â€Ì insbesondere während arktischen Kaltluftausbrüchen â€Ì und der Lagrangeâ€Ìschen Untersuchung atmosphärischer Prozesse nutzen. Im Detail werden wir (i) ein dynamisches Verständnis entwickeln, wie Luftmassentransformationen entlang des Golfstroms die Höhenströmung über Europa beeinflussen, mit Fokus auf blockierenden Hochdruckgebieten, (ii) die Bedeutung von Luftmassentransformationen und diabatischer Prozesse für den Erhalt von Bedingungen, die die Intensivierung von Tiefdruckgebieten während bestimmter Wetterregimelebenszyklen bestimmen, untersuchen, (iii) diese Erkenntnisse in ein einheitliches und quantitatives Bild vereinen, welches die Prozesse, die den Einfluss des Golfstroms auf die großräumige Wettervariabilität prägen, zusammenfasst und (iv) die Güte dieser Prozesse in aktuellen numerischen Vorhersagesystemen bewerten. Diese Grundlagenforschung wird wichtige Erkenntnisse zur Verbesserung von Wettervorhersagemodellen liefern.

Natural variation of flowering time due to cis-regulatory evolution of FLOWERING LOCUS T and its orthologs and paralogs in Brassica napus

In many plant species, FLOWERING LOCUS T and related proteins are the mobile signal that communicates information on photoperiod from the leaves to the shoots, where the transition to flowering is realized. FT expression is tightly controlled at the transcriptional level so that it is restricted to leaves, occurs only in appropriate photoperiods, and integrates ambient temperature and developmental cues, as well as information on biotic and abiotic stress. We previously established that FT transcription in the model plant Arabidopsis thaliana requires proximal promoter cis-elements and a distal enhancer, both evolutionary conserved among Brassicacea species. In addition, FT transcription is blocked prior vernalization in biannual accessions and vernalization-dependency of FT is controlled through a CArG-box located in the first intron that binds the transcriptional repressor FLOWERING LOCUS C (FLC). Chromatin-mediated repression by the Polycomb Group (PcG) pathway is required for photoperiod-dependent FT regulation and participates in FT expression level modulation in response to other cues.In this project, I propose to explore the available sequence data from the 1001 genome project in Arabidopsis to evaluate how often changes in regulatory cis-elements at FT have occurred and how these translate into an adaptive value. Allele-specific FT expression pattern will be measured in F1 hybrids of different accessions in response to varying environmental conditions. FT alleles that show cis-regulatory variation will be further analyzed to pinpoint the causal regulatory changes and study their effect in more detail. The allotetrapolyploid species Brassica napus is a hybrid of two Brassiceae species belonging to the A- and C-type genome, which are in turn mesopolyploid due to a genome triplication that occurred ca. 10x106 years ago. We will determine allele-specific expression of FT paralogs from both genomes of a collection of B. napus accessions. The plants will be grown in the field in changing environmental conditions to maximize the chance to detect expression variation of the paralogs. We will compare the contribution of the founder genomes to the regulation of flowering time and asses variation in this contribution. A particular focus will be to study the impact of chromatin-mediated repression on allele selection in B. napus.

Effect of diffusive/dispersive processes on stable isotope ratios of organic contaminants in aquifer systems

Groundwater contamination by organic compounds represents a widespread environmental problem. The heterogeneity of geological formations and the complexity of physical and biogeochemical subsurface processes, often hamper a quantitative characterization of contaminated aquifers. Compound specific stable isotope analysis (CSIA) has emerged as a novel approach to investigate contaminant transformation and to relate contaminant sources to downgradient contamination. This method generally assumes that only (bio)chemical transformations are associated with isotope effects. However, recent studies have revealed isotope fractionation of organic contaminants by physical processes, therefore pointing to the need of further research to determine the influence of both transport and reactive processes on the observed overall isotope fractionation. While the effect of gasphase diffusion on isotope ratios has been studied in detail, possible effects of aqueous phase diffusion and dispersion have received little attention so far.The goals of this study are to quantify carbon (13C/12C) and, for chlorinated compounds, chlorine (37Cl/35Cl) isotope fractionation during diffusive/dispersive transport of organic contaminants in groundwater and to determine its consequences for source allocation and assessment of reactive processes using isotopes. The proposed research is based on the combination of high-resolution experimental studies, both at the laboratory (i.e. zero-, one- and two-dimensional systems) and at the field scales, and solute transport modeling. The project combines the expertise in the field of contaminant transport with the expertise on isotope methods in contaminant hydrogeology.

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