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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.

Schwerpunktprogramm (SPP) 1158: Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; Bereich Infrastruktur - Antarktisforschung mit vergleichenden Untersuchungen in arktischen Eisgebieten, Identifying the Predominant Sources of Atmospheric Dust to the Antarctic using Peat Cores from Ombrotrophic Sphagnum Bogs in Patagonia

Antarctic ice cores document considerable variation in the fluxes of atmospheric soil dust, volcanic ash particles, and trace metals, but the records are incomplete and the predominant sources of these aerosols are poorly characterised with respect to space and time. Ombrotrophic peat bogs are excellent archives of most atmospheric particles and a wide range of trace metals, and are abundant in Tasmania, New Zealand and Patagonia. The study proposed here will represent the first complete, long term (13.000 yr), high resolution reconstruction of atmospheric dust and trace metal deposition for the southern hemisphere. Conservative, lithogenic trace metals (Ti, Y, Zr, Hf, REE) will be used to quantify the changing rates of atmospheric soil dust deposition, and the ration of these elements to Sc will document changes in mineralogy and particle size. Lead and Sr isotope data will be used to identify changes in predominant dust source areas which will provide new insight into Holocene climate change in the southern hemisphere. Arsenic, Ag, Cd, Sb and Pb will be used to estimate anthropogenic contributions to the metal fluxes. In addition, trace elements supplied by volcanoes will be identified using changes in Au and Bi concentrations, and cosmogenic dust using Os and Ir. These new terrestrial records will complement the existing trace metal and dust records from Antarctica snow and ice archives, and fill in a number of important research gaps.

FP6-SUSTDEV, Study of Environmental Arctic Change - Developing Arctic Modelling and Observing Capability for Long-term Environment Studies (SEARCH FOR DAMOCLES)

We are proposing an SSA 'SEARCH for DAMOCLES' that is based on recent initiatives started in Europe and the USA in the field of Arctic marine ecosystems and Global change, with specific emphasis on Arctic Ocean long-term observatories. The SSA will capitalize on opportunities and significant benefits arising from coordination of large scale research programmes such as the European Integrated Project DAMOCLES (Developing Arctic Modelling and Observing Capabilities for Long-term Environmental studies) and the US research program SEARCH (Study of Environmental ARctic Change). 'SEARCH for DAMOCLES', positioned in the domain of Arctic Science, will be particularly timely in the context of the International Polar Year and will significantly contribute to the coordinated implementation of the DAMOCLES and SEARCH work programmes in the field of Global Change and Ecosystems. Close synchronization of these programmes will enhance the acquisition of pan-arctic data sets, and their analysis, the dissemination and archiving of results, as well as heightening public awareness. International workshops and conferences including other partners such as Canada, Russia, and Asian countries (Japan, China, and South Korea), will enable translation of the results into planning of integrated, future activities that will be based on the SSA 'SEARCH for DAMOCLES'. The coordination and synchronization of Arctic programs such as DAMOCLES and SEARCH, through an SSA is a unique opportunity to ensure the necessary pan-arctic coverage of observations and data evaluation for understanding Arctic system variability, avoiding major gaps and unnecessary overlaps. This EU-US SSA will also contribute to promotion and facilitation of future RTD activities via prospective studies, exploratory measures and pilot actions. The EU-US SSA 'SEARCH for DAMOCLES' is proposed for 3 years covering the 3 last years of the 4-year DAMOCLES Integrated Project (2006-2009) and the 2 years of the IPY (2007-2008). Prime Contactor: Universite Pierre et Marie Curie - Paris VI; Paris; France.

Bio-energy chains from perennial crops in South Europe

The overall objective of this project is to define and evaluate complete bioenergy chains from biomass crop production to thermochemical conversion for production of energy specially suitable for southern Europe. The complete chains will be evaluated regarded technical, environmental and economic aspects in order to identify the most promising combinations of biomass resources and technologies. In order to fulfil these objectives four perennial energy crops (Cardoon, Giant reed, Miscanthus and Switch Grass) have been carefully selected, which, due to their different seasonal harvest times, can provide an-all-year around availability of raw material for a subsequent energy production (combustion, gasification or fast pyrolysis). The work in the project is divided into three main phases: The four selected biomass crops will be cultivated in large fields in representative agricultural regions in Greece, Spain, France and Italy and subsequently harvested. Field measurements from these test fields will be used for the technical, economic and environmental analyses in the following work packages. Each crop will be fully characterised and subjected to a comprehensive test programme of combustion, gasification and fast pyrolysis. A report on the technical evaluation of the overall integrated bioenergy chain performance from biomass in the field to a derived heat and/or power product will be produced. An economic assessment will be carried out on the data collected from the first two phases. The overall performance from biomass in the field to a delivered energy product as heat and or power will be measured by reference to the component parts in the chain starting in the field and progressing through each stage of handling and processing to a final marketable product. An overall performance model will be derived to provide consistent comparison between different bio-energy chains. These assessments will be used to identify and prioritise the best combinations of biomass and conversion technology for each country. Work of the Institute of Chemical Engineering Fundamentals and Plant Engineering (GLVT), Graz University of Technology, within the project The role of GLVT in the project is to characterise the four specially selected fuel crops by comprehensive chemical analyses and by performing thermal conversion test runs in a laboratory-scale test reactor and in a pilot-scale combustion plant (100 kWth). During these test runs combustion characteristics such as, slagging, fouling and corrosion tendencies as well as emission potentials (NOX, SOX and particulates), of the fuels investigated, will be measured and evaluated.

North Sea Model Advection Dispersion Study (NOMADS), NOMADS 2: Assessments of model variability

With numerical models being increasingly used in management decisions affecting the marine environment, quantification of the variability expected from model results, both between different models and compared to nature, is important. This project sets out a programme of study directed at a quantification of variability for three-dimensional hydrodynamic advection-dispersion models used in European Seas. The specific objectives of the project are: to establish measurements of variability in terms of cost functions; to carry out sensitivity studies on models by defining input functions and measuring the response of the models to controlled variation of these functions; to provide an assessment of the natural spatial and seasonal variability of the marine system; to assess model spatial and seasonal variability against the natural variability; to carry out a detailed assessment of model variability by direct comparison with suitable observations. The cost functions (a.) will provide the measure of variation. The sensitivity studies (b.) will provide a measure of expected model variability. Objectives (c.) and (d.) will provide measures of the actual variability, and (e.) will provide a detailed assessment of the variability. Within the study, the limitations applied will be: salinity and temperature will be the variables assessed in (c.) and (d.), using data spanning at least 10 years; the domain of study will be the southern North Sea (to 56N); one year (1988/89) will be the focus for direct model-data intercomparison, taking advantage of the availability of UK North Sea Project data.

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, Physical properties, climate signals, and structural features of Tertiary sediments in the Southern McMurdo Sound (Antarctica) derived from downhole logging in the ANDRILL-SMS project

In the framework of the international ANtarctic DRILLing program (ANDRILL) the 1138 m deep core borehole SMS was drilled in the Southern McMurdo Sound (Ross Sea). The investigations of Antarctic Neogene ice sheet variations, of long-term climate evolutions and of the tectonic history of McMurdo Sound represent the main project aims. One part of the German participation in the ANDRILL project is the extensive geophysical logging of the SMS borehole. It delivers a main basis for answering a lot of questions in the scope of the whole project consisting of about 100 scientists. Interpreting the downhole logging data permits among other things to establish a complete lithological log, to characterize the drilled sediments petrophysically, to determine sedimentary structures and to get evidence about palaeoclimatic conditions during up to 19 Mio years. Seismic experiments in the borehole allow linking detailed geological information with shipborne seismic sections. This way, local results can be transformed into spatial information thus providing an important contribution to the understanding of the tectonic structure of the Ross Sea.

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