API src

Found 199 results.

Related terms

Allergenic potential of Ragweed (Ambrosia artemisiifolia) with respect to climate change

Ziel: The objective of our project is to investigate the impact of different natural and anthropogenic environmental and climatic parameters (CO2, ozone, UV-B, drought, nanoparticles, soil and airborne pollutants) on the potentiality for increases of allergenic components in Ragweed pollen. Methode: Acquisition of the complete transcriptome/proteome under constant and the different climatic parameters listed above will be carried out. In addition secondary metabolite analyses and electron microscopy will be performed. In addition secondary metabolite analyses and electron microscopy will be performed.

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.

DFG Trilateral collaboration Deutschland-Israel-Palestine: Wastewater from Olive Oil Mills in Israel and Palestine: Interactions with Soil, Organic Contaminants and Mechanisms of Incorporation into Soil

Due to the often practised uncontrolled disposal into the environment, olive oil production wastewater (OPWW) is presently a serious environmental problem in Palestine and Israel. The objectives of this interdisciplinary trilateral research project are (i) to understand the mechanisms of influence of the olive oil production wastewater on soil wettability, water storage, interaction with organic agrochemicals and pollutants; (ii) monitor short-term and long-term effects of OPWW land application in model laboratory and field experiments; (iii) identify the components responsible for unwanted changes in soil properties and (iv) analyse the mechanisms of association of OPWW OM with soil, the interplay between climatic conditions, pH, presence of multivalent cations and the resulting effects of land application. Laboratory incubation experiments, field experiments and new experiments to study heat-induced water repellency will be conducted to identify responsible OPWW compounds and mechanisms of interaction. Samples from field experiments and laboratory experiments are investigated using 3D excitation-emission fluorescence spectroscopy, thermogravimetry-differential thermal analysis-mass spectrometry (TGA-DSC-MS), LC-MS and GC-MS analyses. We will combine thermal decomposition profiles from OPWW and OPWW-treated soils in dependence of the incubation status using TGA-DSC-MS, contact angle measurements, sorption isotherms and the newly developed time dependent sessile drop method (TISED). The resulting process understanding will open a perspective for OPWW wastewater reuse in small-scale and family-scale olive oil production busi-nesses in the Mediterranean area and will further help to comprehend the until now not fully un-ravelled effects of wastewater irrigation on soil water repellency.

14C content of specific organic compounds in subsoils

Organic matter (OM) composition and dynamic in subsoils is thought to be significantly different from those in surface soils. This has been suggested by increasing apparent 14C ages of bulk soil OM with depth suggesting that the amount of fresh, more easily degradable components is declining. Compositional changes have been inferred from declining ä13C values and C/N ratios indicative for stronger OM transformation. Beside these bulk OM data more specific results on OM composition and preservation mechanisms are very limited but modelling studies and results from incubation experiments suggest the presence and mineralization of younger, 'reactive carbon pool in subsoils. Less refractory OM components may be protected against degradation by interaction with soil mineral particles and within aggregates as suggested by the very limited number of more specific OM analysis e.g., identification of organic compound in soil fractions. The objective of this project is to characterize the composition, transformation, stabilization and bioavailability of OM in subsurface horizons on the molecular level: 1) major sources and compositional changes with depth will be identified by analysis of different lipid compound classes in surface and subsoil horizons, 2) the origin and stabilization of 'reactive OM will be revealed by lipid distributions and 14C values of soil fractions and of selected plant-specific lipids, and 3) organic substrates metabolized by microbial communities in subsoils are identified by distributional and 14C analysis of microbial membrane lipids. Besides detailed analyses of three soil profiles at the subsoil observatory site (Grinderwald), information on regional variability will be gained from analyses of soil profiles at sites with different parent material.

Das Energiewende-Szenario 2020 - Ausstieg aus der Atomenergie, Einstieg in Klimaschutz und nachhaltige Entwicklung

Development of an integrated forest carbon monitoring system with field sampling and remote sensing for tropical forests in Indonesia

Forests play a relevant role in mitigation of climate change. A major issue, however, is the scientifically well founded, transparent and verifyable monitoring of achievements in forest carbon sequestration through reduction of deforestation and forest degradation, and through fostering sustainable forest management. Monitoring is particularly difficult in diverse and inaccessible humid tropical forest areas. The proposed research will contribute to the improvement of forest carbon monitoring under the challenging conditions of humid tropical forests. Sample based field observations and model based biomass predictions will be linked to area-wide satellite remote sensing imagery (RapidEye) and to strip samples of LiDAR imagery. Techniques of linking these data sources will be further developed and analysed with respect to (1) precision of carbon estimation and (2) accuracy of carbon regionalization. The proposed project implies research on methodological improvements of both sample based forest inventories (resampling techniques for biomass, imputation of non-response) and remote sensing application to forest monitoring (regionalization, sample based application of LiDAR data). At the core of this research is the analysis of the error variance components that each data source brings into the system. Such error analysis will allow identifying optimal resource allocation for the efficient improvement of forest carbon monitoring systems.

SP 1.5 Molekulare Charakterisierung von gelösten organischen Stoffen in der Meeresoberflächen-Mikroschicht (SML) und deren Einfluss auf den anorganischen Kohlenstoffkreislauf

Unsere Motivation ist es, die Rolle von gelöstem organischem Material (DOM) in marinen Oberflächenfilmen (SML) als eine Schlüsselkomponente zu verstehen, die den Gasaustausch zwischen Atmosphäre und Meer, die Karbonatchemie, sowie die Ökophysiologie der assoziierten Organismen beeinflusst (Engel et al., 2017). Während unserer Vorarbeiten haben wir Hinweise auf einen bisher unbekannten Zusammenhang zwischen DOM und Karbonatchemie in der SML gefunden, sowie auf eine hohe räumlich-zeitliche Dynamik in der DOM-Zusammensetzung. Obwohl die hohe Heterogenität des SML-DOM-Geometabolom (d.h. die Gesamtheit des DOM-Pools, der durch biotische und abiotische Prozesse produziert und modifiziert wird) bekannt ist, gibt es wenige detaillierte Studien darüber. Insgesamt gibt es noch kein mechanistisches Verständnis darüber, unter welchen Bedingungen DOM in der SML in verschiedene chemische Fraktionen aufgeteilt wird. Dies liegt an der derzeit geringen Verfügbarkeit von Daten von einer größeren Anzahl von Untersuchungsstandorten unter unterschiedlichen Umwelt- und Versuchsbedingungen, sowie an einen Mangel an interdisziplinären Studien, die Physik, Geochemie und Biologie kombinieren. Mit anderen Worten, uns fehlen grundlegende (organo-)geochemische Informationen von der größten Luft-Wasser-Grenzfläche der Erde, mit unbekannten Konsequenzen für den damit verbundenen Austausch von klimarelevanten Gasen. In diesem Projekt streben wir an, diese Lücke durch sich ergänzende Messungen der DOM-Zusammensetzung und anorganischer Kohlenstoff-Systemparameter zu schließen. Die Relevanz für die Forschungseinheit BASS ergibt sich aus dem Ziel unseres Teilprojekts, die fehlenden grundlegenden biogeochemischen Informationen des SML-DOM-Inventars zur Verfügung zu stellen und sie in den Kontext der Ökosystemprozesse in der SML zu setzen, einschließlich der DOM-Produktion (SP1.1) sowie des mikrobiellen (SP1.2) und photochemischen (SP1.4) Umsatzes. Darüber hinaus werden wir den Beitrag des DOM-Geometaboloms zum Säure-Basen-Gleichgewicht der SML untersuchen, von dem wir erwarten, dass es die Gasgleichgewichte in der Grenzfläche - insbesondere im Kohlensäuresystem und damit auch die Treibhausgasflüsse - beeinflusst (SP2.1).

Revision of basal sauropods from the Middle Jurassic of Patagonia and the early evolution of eusauropods

Sauropod dinosaurs represent one of the most important components of Mesozoic terrestrial vertebrate faunas, yet their early evolution and diversification in the Jurassic is still poorly understood. Furthermore, most of the pertinent data so far comes from Early and Middle Jurassic rocks in eastern Asia. The only abundant basal sauropod material reported from the Western Hemisphere so far comes from the Middle Jurassic Cañadón Asfalto Formation of Chubut province, Argentina, from where two species, Patagosaurus fariasi and Volkheimeria chubutensis, have been described. Especially the first of these taxa has figured prominently in basal sauropod phylogenies. However, recent research suggests that more sauropods are represented in the original material referred to this species, and intensive fieldwork in the rocks that have yielded these materials has resulted in the recovery of a wealth of new material. Thus, the objective of this project is a revision of the original materials of Patagosaurus as well as an incorporation of new materials. The alpha taxonomy of the sauropods from the Cañadón Asfalto Formation will be established, detailed osteological descriptions of the different taxa provided and their significance for our understanding of early sauropod evolution will be evaluated.

Profiling methane emission in the Baltic Sea: Cryptophane as in-situ chemical sensor

To overcome the limitation in spatial and temporal resolution of methane oceanic measurements, sensors are needed that can autonomously detect CH4-concentrations over longer periods of time. The proposed project is aimed at:- Designing molecular receptors for methane recognition (cryptophane-A and -111) and synthesizing new compounds allowing their introduction in polymeric structure (Task 1; LC, France); - Adapting, calibrating and validating the 2 available optical technologies, one of which serves as the reference sensor, for the in-situ detection and measurements of CH4 in the marine environments (Task 2 and 3; GET, LAAS-OSE, IOW) Boulart et al. (2008) showed that a polymeric filmchanges its bulk refractive index when methane docks on to cryptophane-A supra-molecules that are mixed in to the polymeric film. It is the occurrence of methane in solution, which changes either the refractive index measured with high resolution Surface Plasmon Resonance (SPR; Chinowsky et al., 2003; Boulart et al, 2012b) or the transmitted power measured with differential fiber-optic refractometer (Boulart et al., 2012a; Aouba et al., 2012).- Using the developed sensors for the study of the CH4 cycle in relevant oceanic environment (the GODESS station in the Baltic Sea, Task 4 and 5; IOW, GET); GODESS registers a number of parameters with high temporal and vertical resolution by conducting up to 200 vertical profiles over 3 months deployment with a profiling platform hosting the sensor suite. - Quantifying methane fluxes to the atmosphere (Task 6); clearly, the current project, which aims at developing in-situ aqueous gas sensors, provides the technological tool to achieve the implementation of ocean observatories for CH4. The aim is to bring the fiber-optic methane sensor on the TRL (Technology Readiness Level) from their current Level 3 (Analytical and laboratory studies to validate analytical predictions) - to the Levels 5 and 6 (Component and/or basic sub-system technology validation in relevant sensing environments) and compare it to the SPR methane sensor, taken as the reference sensor (current TRL 5). This would lead to potential patent applications before further tests and commercialization. This will be achieved by the ensemble competences and contributions from the proposed consortium in this project.

Biogeochemical reactivity of Fe-organic matter coprecipitates

Iron(III) (hydr)oxide-organic associations in soils have been recognized to play an important role in the biogeochemical cycling of iron, carbon, and of nutrients like phosphate. In temporarily moist or water-logged soils such associations can form via the coprecipitation of dissolved organic matter (OM) with Fe(III) (hydr)oxides (FHOs). At present, it is generally unknown which factors control the formation and composition of Fe(III)-OM coprecipitates and how the structural properties translate into the cycling of the FHO and OM component involved. The objectives of the project are thus to elucidate (i) the structural properties of Fe(III)- OM coprecipitates under different environmental conditions, (ii) the subsequent stability of Fe(III)-OM coprecipitates against dissolution under both oxic as well as anoxic conditions, (iii) the changes in Fe(III)-OM coprecipitate composition upon redox oscillations, and (iii) their cumulative effects on oxyanion sorption. To achieve these goals, various batch experiments will be conducted. By using multiple analytical tools, this project will gain a fundamental understanding of the abiotic and biotic controls on the formation, structure, and biogeochemical reactivity of Fe(III)-OM coprecipitates in acidic and neutral temporarily moist soils and soils subject to redox oscillations.

1 2 3 4 518 19 20