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Monsunvariabilität in SE-China - der Huguang-Maarsee (Huguangyan)

Südchina, insbes. die Provinz Guandong, ist eines der am dichtesten besiedelten Gebiete der Erde. Positive Konsequenz dieser Ballung ist eine äußerst dynamische Wirtschaftsentwicklung, aber gerade diese von subtropischem Monsunklima geprägte Region ist auch immer wieder Ausgangspunkt für sich schnell und zunehmend global ausbreitende epidemische Krankheiten wie zuletzt SARS. Mit der globalen Erwärmung einhergehende Klimaveränderungen könnten sich für diese Region insbesondere durch Veränderungen der Häufigkeit und Intensität tropischer Wirbelstürme, aber auch Änderungen der Niederschlagsmenge- und Intensität bemerkbar machen. Im Gegensatz zu den schon recht umfangreichen Datensätzen aus der Südchinesischen See (SCS) gibt es bisher jedoch nur sehr wenige terrestrische Paläoklimaarchive aus der Region, die Klimaveränderungen während des Holozäns, des Spätglazials oder Glazials hochauflösend dokumentieren. Wir haben deshalb einen an der nördlichen Küste der SCS gelegenen Maarsee ausgewählt, um über die Analyse von Proxydaten aus Seesedimenten solche Paläo-Klimavariationen zu untersuchen. Aus dem Sediment des Huguang-Maarsees wurden mittels Usinger-Präzisionsstechtechnik von einem Floss aus insgesamt 7 Sedimentsequenzen gewonnen, von denen die tiefste bis 57 m unter den Seeboden reicht. Die zeitliche Einstufung der Profile wurde mit Hilfe von 17 Radiokohlenstoff-Datierungen vorgenommen und ergab ein extrapoliertes Maximalalter von ca. 78.000 Jahren. Ein breites Spektrum aus sedimentologischen, geochemischen, paläo- und gesteinsmagnetischen sowie palynologischen Methoden kam sodann zum Einsatz, um die Paläo-Umweltbedingungen, die natürlich immer das entsprechende Klima widerspiegeln, während dieses Zeitraumes zu rekonstruieren. Überraschenderweise ergab sich ein von vielen bekannten Klimaprofilen der Nordhemisphäre (insbes. des Atlantikraumes, aber auch mariner Kerne aus dem Indik und Südostasien) abweichendes Muster. Im Gegensatz zu dem bekannten Grundmuster eines vergleichsweise stabilen Klimas während des Holozäns und stärkerer Schwankungen während des letzten Glazials weisen die Daten aus dem Huguang-Maarsee für das letzte Glazial im Zeitraum zwischen 15.000 und 40.000 Jahren auf relativ stabile Umweltbedingungen hin. Die älteren Bereiche zwischen 40.000 und ca. 78.000 Jahren haben durch Eintrag von umgelagertem Torf eine eher lokale Komponente und sind somit für den regionalen und globalen Vergleich ungeeignet. Das Holozän hingegen zeichnet sich durch hohe Schwankungsamplituden vieler Proxydaten (Karbonatgehalt, magnetische Suszeptibilität, organischer Kohlenstoff, Trockendichte, gesteinsmagnetische Parameter, Redox-Verhältnisse) aus, die auf ein recht variables Klima hinweisen. Besonders interessant ist die Übergangsphase vom Glazial zum Holozän, die bei etwa 15.000 Jahren vor heute in etwa zeitgleich mit dem beobachteten stärksten Meeresspiegelanstieg der Südchinesischen See einsetzt und eine abrupte Intensitätszunahme des Sommermonsuns anzeigt

Solar Steam Reforming of Methane Rich Gas for Synthesis Gas Production (SOLREF)

Project main goals: The main purpose of this project is to develop an innovative 400 kWth solar reformer for several applications such as Hydrogen production or electricity generation. Depending of the feed source for the reforming process CO2 emissions can be reduced significantly (up to 40 percent using NG), because the needed process heat for this highly endothermic reaction is provided by concentrated solar energy. A pre-design of a 1 MW prototype plant in Southern Italy and a conceptual layout of a commercial 50 MWth reforming plant complete this project. Key issues: The profitability decides if a new technology has a chance to come into the market. Therefore several modifications and improvements to the state-of-the-art solar reformer technology will be introduced before large scale and commercial system can be developed. These changes are primarily to the catalytic system, the reactor optimisation and operation procedures and the associated optics for concentrating the solar radiation. For the dissemination of solar reforming technology the regions targeted are in Southern Europe and Northern Africa. The potential markets and the impact of infrastructure and administrative restrictions will be assessed. The environmental, socio-economic and institutional impacts of solar reforming technology exploitation will be assessed with respect to sustainable development. The market potential of solar reforming technology in a liberalised European energy market will be evaluated. Detailed cost estimates for a 50 MWth commercial plant will be determined.

Schwerpunktprogramm (SPP) 1158: Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten, Genetic diversity and geographical differentiation of green-algal photobionts in Antarctic lichens

The biomass and diversity of terrestrial Antarctic ecosystems is almost entirely made up of bryophytes and lichens. As highly specialized symbiotic systems of fungi and algae or cyanobacteria lichens are especially sensitive to rapid climatic changes. Lichen fungi depend critically on the availability and ecological performance of suitable algal strains and genotypes in their environment. Up to now, the genetic diversity and geographical differentiation of Antarctic green algal lichen photobionts has not been studied in detail and little is known about the photobiont selectivity of green algal lichens. Based on DNA-sequences, we study the genetic diversity and structure of Antarctic populations of trebouxioid lichen photobionts and mycobionts and compare them with populations from other continents. As a model system, the photobiont diversity in different haplotypes of the macrolichen Cetraria aculeata is examined and compared to the genetic diversity of Cetraria-mycobionts and the total organismal stand diversity. We are especially interested in the question, how strongly Antarctic populations of C. aculeata select for certain photobiont strains and whether Antarctic photobiont populations are genetically isolated from those of other continents. First results indicate reduced levels of genetic diversity in Antarctic mycobiont and photobiont populations. The photobiont of Cetraria aculeata belongs to the Trebouxia jamesii group. With the exception of a few rare haplotypes, there seem to be no specifically Antarctic haplotypes. Most notably, Antarctic photobiont haplotypes are closely related to or even identical with arctic haplotypes, while temperate populations of Cetraria aculeata associate with genetically different photobionts. Although C. aculeata is usually sterile and propagates by thallus fragments that contain both symbionts, the mycobiont displays a different phylogeographic pattern with northern and southern hemispheric haplotypes. This indicates habitat-specific association of mycobionts with photobionts.

Potential of the medicinal plant Passiflora incarnata L. as cover crop in fruit tree plantations in North Thailand

Erosion of the often uncovered soil is a major problem for the establishment of smallholder fruit tree plantations in North Thailand. The use of multi-purpose cover plants can not only conserve useful soil resources but also create further income for peasants. Dried plant material from the passion flower (Passiflora incarnata L.) is used for herbal tea and extracts to be used as sedativa. The species is widespread in the Southern USA. The drug is often produced based on wild collections and exported to Europe. In exploratory trials in Thailand passion flower showed a good drought resistance due to its deep rooting system, and a good resistance against weeds and diseases. The yield potential and the amounts of ingredients appear to be promising with regard for the adoption by farmers. The flavonoids in the passion flower are mostly flavone-C-glycosides and are used for characterisation of the drug. Quantitative studies of imported drug material showed large differences in quantities and types of the flavone-C-glycosides. The causes for these differences are still not understood. Not much is known about the effect of cultivation techniques, fertilizer, growth stage on the content of flavonoids. The objective of this project is to study the potential of the passion flower as a soil cover plant in smallholder fruit tree plantations in North Thailand. Factors to be monitored are the effects of fertilizer and growth stage at harvest on plant yield and components.

Strategy and methodology for improved IWRM - An integrated interdisciplinary assessment in four twinning basins (STRIVER)

The ZEF research focuses on the Tungabhadra basin in south India, which is one of the four basins studied in the project. Tungabhadra river is a tributary of the Krishna river. ZEF will be mainly active in Work Package (WP) 9 IWRM in the twinned Tungabhadra and Tejo/Tagus river basins, with a focus and land and water use interactions . The research focuses on the interaction between irrigated and rainfed farming in the lower Tungabhadra basin, in the border area of the states of Karnataka and Andhra Pradesh. The districts on the Karnataka side are Raichur, Koppal and Bellary, on the Andhra Pradesh side Mahbubnagar and Kurnool. Some of the sub-themes ZEF will look at, together with other partners, are: 1) Flows and relations (people (livelihood linkages, labour), nutrients and energy, money/income, water); 2) Institutional and policy (dis)integration (departmental coordination, agency coordination, policy contradictions and alignments); 3) Innovations (water saving farming systems (SRI and other), (tiered) water users associations, water pricing and water rights, substitutability of technical and institutional solutions to water problems); 4) History (heads and tails of different kinds: the spatial dimension of social differentiation; evolution of policy regimes, natural resources degradation/conservation in historical perspective, land and water use change over time and its implications). It is part of the research design to compare the situation in the Tungabhadra basin with that in the Tajo/Tegus basin in Spain/Portugal. Other basins studied in the larger project are the Glomma basin in Norway and the Sesan basin in Vietnam/Cambodia).

Schwerpunktprogramm (SPP) 1144: Vom Mantel zum Ozean: Energie-, Stoff- und Lebenszyklen an Spreizungsachsen, Primordiales Helium und vertikale Vermischung am Mittelatlantischen Rücken zwischen 2 S - 11 S

Das Schwerpunktprogramm 1144 der DFG hat es sich zum Ziel gesetzt, Energie- Stoff- und Lebenszyklen an Spreizungsachsen vom Mantel zum Ozean zu untersuchen. Mit dem hier vorliegenden Antrag wollen wir einen Beitrag leisten, den Export von hydrothermalen Produkten in den Ozean anhand der Plume Dynamik zu quantifizieren. Die Hauptziele des vorliegenden Antrags umfassen die Untersuchung des Effekts gezeitengetriebener interner Wellen und vertikaler Vermischung auf die vertikale Ausbreitung/Verdünnung des Plumes und auf die Verteilung der hydrothermalen Fluide und Gase; die Untersuchung der Plume Dynamik durch Beobachtung von Turbulenzstärke, Geschwindigkeitsverteilung und Schichtung im Nahbereich der Quelle; die Quantifizierung des Helium- und Wärmeflusses der Hydrothermalquelle; die Quantifizierung der zeitlichen Variabilität der Volumen- Wärme- und Heliumtransporte aus dem Quellgebiet in den offenen Ozean; Wir werden Schiffs- und ROV-gestützte Messungen von Strömungsgeschwindigkeiten, Dichteschichtung, Trübung sowie Helium Probenahme durchführen um damit das Nahfeld und die grossräumige Ausbreitung des Plumes eines Hydrothermalfeldes zu untersuchen. Zur Bestimmung der zeitlichen Variabilität werden diese Daten mit verankerten Zeitreihen von Strömungsmessern mit Temperatur- und zusätzlichen Trübungssensoren kombiniert. Die so gewonnenen Daten liefern Informationen in Bezug auf die Kopplung zwischen physikalischen, geochemischen und biologischen Prozessen: das Strömungsfeld an Hydrothermalquellen hat direkten Einfluss auf die Besiedlungsmuster und -strategien von Vent Spezies; die Analyse des Heliumsignals in der Wassersäule liefert Informationen bezüglich der geochemischen Prozesse in Hydrothermalsystemen. Die Variabilität und Stärke der Helium- und Wärmeflüsse eines Hydrothermalfeldes erlaubt Aussagen über den Export eines solchen Feldes und seiner Variabilität in Relation zu ozeanographischen und geophysikalischen Randbedingungen. Der Schwerpunkt der Arbeiten wird bei 4 Grad 48S liegen.

TIPTEQ: from The Incoming Plate to mega-Thrust EarthQuake processes, TIPTEQ 1 - Sonderprogramm GEOTECHNOLOGIEN

Convergent continental margins are the site of large earthquakes originating along the interface between the subducting and overriding plates. The site of the strongest historically recorded earthquake (Mw=9.5, 1960) is the study area of the ongoing TIPTEQ project (2004-2007) in Chile. Here, in southern central Chile the project investigates the controlling parameters of processes leading to earthquakes in the seismogenic coupling zones (add link to more detailed TIPTEQ pages). Along the plate margin the oceanic Nazca plate subducts below the South American continent. Thereby, material is accreted and folded, faults are generated, material is transported to large depths where it is possibly accreteded at the base of the upper plate. These structures and processes are the targets of geophysical imaging and - together with geological surface observations- form the basis for numerical and analog simulations of active margin deformation and the the processes leading to mega-thrust earthquakes. First pilot studies in 2001 (project SPOC) have shown that the target area is well suited for our investigations. Our contributions to TIPTEQ: Seismic and structural image of the plate interface, Co-seismic mass transfer and surface processes, Experimental and numerical analysis of deformation processes Simulation of surface deformation during subduction earthquakes.

Forschergruppe (FOR) 816: Biodiversity and Sustainable Management of a Megadiverse Mountain Ecosystem in South Ecuador, A3.3: Spatiotemporal dynamics of shallow landslides and their biotic and abiotic controls - an integrating synthesis including soil landscape modeling for determination and regionalisation of soil functional groups as well as forest modeling

Winter damage on apple trees: causes, effects and avoidance strategies

South Tirol is an important region for apple production in Europe. The mild climate allows a high productivity but during the last decades, winter damage on apple trees was observed in 3 to 4 year intervals at numerous sites in South Tirol. This winter damage in apple orchards is economically relevant as e.g. in season 2004/2005 costs of more than 6 Mio Euros were caused. There are several indications that the observed dieback of crown parts or even trees was related to frost drought. The situation is comparable to that of trees at the timberline, where winter damage was analysed in previous projects. Based on our experience with trees growing at the alpine timberline, we hypothesize that winter damage in South Tirol apple orchards is strongly influenced by the duration of water uptake blockages, the extent of transpirational water losses, the trees water storage capacity as well as the climatic conditions in autumn. We expect damage in living tissues as well as xylem embolism to cause prolonged drought stress in spring. In the proposed project, these aspects will be analysed and avoidance strategies will be developed. In field measurements at five apple orchards in South Tirol, climatic conditions and effects on tree water relations (water potential, hydraulic conductivity, water storage, transpiration) as well as winter injury will be quantified, and in experimental approaches important parameters will be analysed in detail. These data will be compared with hydraulic characteristics (vulnerability to embolism, drought resistance of living tissues, water storage capacity) of studied varieties. In consequence, numerous varieties will be screened for resistance to frost drought, whereby hydraulic as well as related anatomical parameters will be analysed to develop a valuable screening protocol for variety selection. Cultivation techniques to avoid winter damage will also be tested in thi u.s.w.

Schwerpunktprogramm (SPP) 1158: Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten, Neogene Paleoenvironmental changes in the McMurdo Sound region: High resolution chemical and sedimentological analysis of Miocene (ca17 Ma) to Pleistocene sediments from ANDRILL Site SMS

At ANDRILL site SMS (Southern McMurdo Sound) an longer than 1000m sediment core will be drilled from a sea-ice platform covering Early/Middle Miocene (ca17 Ma) to Pleistocene strata of McMurdo Sound, Ross Sea, Antarctica. The target sediments were deposited on the western flank of the Victoria Land Basin (VLB), a structural half-graben that forms part of the West Antarctic Rift system, and experienced subsidence since late Eocene times. On this sediment core we propose to combine high-resolution on-ice measurement of chemical element concentrations using XRF core-scanner with off-ice high-precision chemical and sedimentological analysis on bulk samples (XRF, XRD, ICP-MS, biogenic components) and individual lithoclasts (LA-ICP-MS, electron microprobe, microscopy). The resulting multiple dataset will provide detailed information on sediment composition and, thus, contribute to several scientific objectives of ANDRILL such as the history of Ross/West Antarctic ice shelf expansion and retreat since ca17 million years, sea-ice presence/absence in the McMurdo region, and the history of Neogene sediment provenance and accumulation rates in the VLB. Our major goal is to improve our understanding of the Neogene paleoenvironmental evolution of Antarctica with a special focus on the Mid-Miocene climatic optimum (ca17-15 Ma) and the subsequent onset of major cooling (ca14 Ma) along with the key question on the stability of cold-polar climate conditions during the last 14 million years

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