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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.

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

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.

Methodologies for dealing with uncertainties in landscape planning and related modeling; Uncertainty of predicted hydro-biogeochemical fluxes and trace gas emissions on the landscape scale under climate and land use change

Water, carbon and nitrogen are key elements in all ecosystem turnover processes and they are related to a variety of environmental problems, including eutrophication, greenhouse gas emissions or carbon sequestration. An in-depth knowledge of the interaction of water, carbon and nitrogen on the landscape scale is required to improve land use and management while at the same time mitigating environmental impact. This is even more important under the light of future climate and land use changes.In the frame of the proposal 'Uncertainty of predicted hydro-biogeochemical fluxes and trace gas emissions on the landscape scale under climate and land use change' we advocate the development of fully coupled, process-oriented models that explicitly simulate the dynamic interaction of water, carbon and nitrogen turnover processes on the landscape scale. We will use the Catchment Modelling Framework CMF, a modular toolbox to implement and test hypothesis of hydrologic behaviour and couple this to the biogeochemical LandscapeDNDC model, a process-based dynamic model for the simulation of greenhouse gas emissions from soils and their associated turnover processes.Due to the intrinsic complexity of the models in use, the predictive uncertainty of the coupled models is unknown. This predictive (global) uncertainty is composed of stochastic and structural components. Stochastic uncertainty results from errors in parameter estimation, poorly known initial states of the model, mismatching boundary conditions or inaccuracies in model input and validation data. Structural uncertainty is related to the flawed or simplified description of natural processes in a model.The objective of this proposal is therefore to quantify the global uncertainty of the coupled hydro-biogeochemical models and investigate the uncertainty chain from parameter uncertainty over forcing data uncertainty up the structural model uncertainty be setting up different combinations of CMF and LandscapeDNDC. A comprehensive work program has been developed structured in 4 work packages, that consist of (1) model set up, calibration and uncertainty assessment on site scale followed by (2) an application and uncertainty assessment of the coupled model structures on regional scale, (3) global change scenario analyses and finally (4) evaluating model results in an ensemble fashion.Last but not least, a further motivation of this proposal is to provide project results in a manner that they support planning and decision taking under uncertainty, as this proposal is part of the package proposal on 'Methodologies for dealing with uncertainties in landscape planning and related modelling'.

Forschergruppe (FOR) 861: Cross-scale Monitoring: Biodiversity and Ecosystem Functions, Quantification of functional hydro-biogeochemical indicators in Ecuadorian ecosystems and their reaction on global change

Water is an intrinsic component of ecosystems acting as a key agent of lateral transport for particulate and dissolved nutrients, forcing energy transfers, triggering erosion, and driving biodiversity patterns. Given the drastic impact of land use and climate change on any of these components and the vulnerability of Ecuadorian ecosystems with regard to this global change, indicators are required that not merely describe the structural condition of ecosystems, but rather capture the functional relations and processes. This project aims at investigating a set of such functional indicators from the fields of hydrology and biogeochemistry. In particular we will investigate (1) flow regime and timing, (2) nutrient cycling and flux rates, and (3) sediment fluxes as likely indicators. For assessing flow regime and timing we will concentrate on studying stable water isotopes to estimate mean transit time distributions that are likely to be impacted by changes in rainfall patterns and land use. Hysteresis loops of nitrate concentrations and calculated flux rates will be used as functional indicators for nutrient fluxes, most likely to be altered by changes in temperature as well as by land use and management. Finally, sediment fluxes will be measured to indicate surface runoff contribution to total discharge, mainly influenced by intensity of rainfall as well as land use. Monitoring of (1) will be based on intensive sampling campaigns of stable water isotopes in stream water and precipitation, while for (2) and (3) we plan to install automatic, high temporal-resolution field analytical instruments. Based on the data obtained by this intensive, bust cost effective monitoring, we will develop the functional indicators. This also provides a solid database for process-based model development. Models that are able to simulate these indicators are needed to enable projections into the future and to investigate the resilience of Ecuadorian landscape to global change. For the intended model set up we will couple the Catchment Modeling Framework, the biogeochemical LandscapeDNDC model and semi-empirical models for aquatic diversity. Global change scenarios will then be analyzed to capture the likely reaction of functional indicators. Finally, we will contribute to the written guidelines for developing a comprehensive monitoring program for biodiversity and ecosystem functions. Right from the beginning we will cooperate with four SENESCYT companion projects and three local non-university partners to ensure that the developed monitoring program will be appreciated by locals and stakeholders. Monitoring and modelling will focus on all three research areas in the Páramo (Cajas National Park), the dry forest (Reserva Laipuna) and the tropical montane cloud forest (Reserva Biologica San Francisco).

Flowering time, development and yield in oilseed rape (Brassica napus): Sequence diversity in regulatory genes

Flowering time (FTi) genes play a key role as regulators of complex gene expression networks, and the influence of these networks on other complex systems means that FTi gene expression triggers a cascade of regulatory effects with a broad global effect on plant development. Hence, allelic and expression differences in FTi genes can play a central role in phenotypic variation throughput the plant lifecycle. A prime example for this is found in Brassica napus, a phenotypically and genetically diverse species with enormous variation in vernalisation requirement and flowering traits. The species includes oilseed rape (canola), one of the most important oilseed crops worldwide. Previously we have identified QTL clusters related to plant development, seed yield and heterosis in winter oilseed rape that seem to be conserved in diverse genetic backgrounds. We suspect that these QTL are controlled by global regulatory genes that influence numerous traits at different developmental stages. Interestingly, many of the QTL clusters for yield and biomass heterosis appear to correspond to the positions of meta-QTL for FTi in spring-type and/or winter-type B. napus. Based on the hypothesis that diversity in FTi genes has a key influence on plant development and yield, the aim of this study is a detailed analysis of DNA sequence variation in regulatory FTi genes in B. napus, combined with an investigation of associations between FTi gene haplotypes, developmental traits, yield components and seed yield.

Forschergruppe (FOR) 1525: INUIT - Ice Nuclei research UnIT, Screening und Charakterisierung biologischer Eiskeime und Untersuchung deren Einflusses auf die Eiskeimaktivität von Boden-und Mineralstaub

Mikroorganismen sind im Boden, in kryptogamen Gemeinschaften und in der Atmosphäre von zentraler Bedeutung. Verschiedene Spezies von Bakterien, Pilzen, Flechten und Pollen wurden bereits als Eiskeime, welche eine Eisbildung bei relativ hohen Temperaturen initiieren können, identifiziert, und besonders biologische Bestandteile aus dem Boden sind eine vermutlich bedeutsame Quelle atmosphärischer Eiskeime. Die genauen Quellen biologischer Eiskeime in der Atmosphäre sind jedoch kaum bekannt, obwohl ein potentieller Beitrag dieser, zur Eis- und Niederschlagsbildung mittlerweile von verschiedenen Studien untermauert wird. Aktuelle Untersuchungen verschiedener Boden- und Luftproben zeigen Hinweise, dass verschiedene eisaktive Pilze unterschiedlicher Phyla nicht nur im Boden und in der Luft vorhanden sind, sondern auch häufig in der kultivierbaren Fraktion vorkommen können. Aus diesem Grund befasst sich das vorgeschlagene Projekt mit der Suche nach weiteren bisher unbekannten eisaktiven Mikroorganismen und Bestandteilen aus dem Boden, von Pflanzen und kryptogamen Gemeinschaften und mit der Erforschung ihres Einflusses auf die Eiskeimaktivität des Bodens. Die nötigen Methoden für ein Screening verschiedenster Kulturen z.B. von Cyanobakterien sind in unserem Labor gut etabliert. Zudem sollen die jeweiligen Eiskeime der neu gefundenen eisaktiven Organismen auf molekularer Ebene charakterisiert werden.

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).

Forschergruppe (FOR) 1806: The Forgotten Part of Carbon Cycling: Organic Matter Storage and Turnover in Subsoils (SUBSOM)

We are currently facing the urgent need to improve our understanding of carbon cycling in subsoils, because the organic carbon pool below 30 cm depth is considerably larger than that in the topsoil and a substantial part of the subsoil C pool appears to be much less recalcitrant than expected over the last decades. Therefore, small changes in environmental conditions could change not only carbon cycling in topsoils, but also in subsoils. While organic matter stabilization mechanisms and factors controlling its turnover are well understood in topsoils, the underlying mechanisms are not valid in subsoils due to depth dependent differences regarding (1) amounts and composition of C-pools and C-inputs, (2) aeration, moisture and temperature regimes, (3) relevance of specific soil organic carbon (SOC) stabilisation mechanisms and (4) spatial heterogeneity of physico-chemical and biological parameters. Due to very low C concentrations and high spatio-temporal variability of properties and processes, the investigation of subsoil phenomena and processes poses major methodological, instrumental and analytical challenges. This project will face these challenges with a transdisciplinary team of soil scientists applying innovative approaches and considering the magnitude, chemical and isotopic composition and 14C-content of all relevant C-flux components and C-fractions. Taking also the spatial and temporal variability into account, will allow us to understand the four-dimensional changes of C-cycling in this environment. The nine closely interlinked subprojects coordinated by the central project will combine field C-flux measurements with detailed analyses of subsoil properties and in-situ experiments at a central field site on a sandy soil near Hannover. The field measurements are supplemented by laboratory studies for the determination of factors controlling C stabilization and C turnover. Ultimately, the results generated by the subprojects and the data synthesized in the coordinating project will greatly enhance our knowledge and conceptual understanding of the processes and controlling factors of subsoil carbon turnover as a prerequisite for numerical modelling of C-dynamics in subsoils.

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