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

Das Projekt "Flowering time, development and yield in oilseed rape (Brassica napus): Sequence diversity in regulatory genes" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Justus-Liebig-Universität Gießen, Institut für Pflanzenbau und Pflanzenzüchtung I, Professur für Pflanzenzüchtung.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.

Coordination and administration of the priority programme SPP 1315 Biogeochemical Interfaces in Soil, Biotic and abiotic factors that dive the function of microbial communities at biogeochemical interfaces in different soils (BAMISO)

Das Projekt "Coordination and administration of the priority programme SPP 1315 Biogeochemical Interfaces in Soil, Biotic and abiotic factors that dive the function of microbial communities at biogeochemical interfaces in different soils (BAMISO)" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Helmholtz Zentrum München Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Abteilung für Umweltgenomik.Biogeochemical interfaces shape microbial community function in soil. On the other hand microbial communities influence the properties of biogeochemical interfaces. Despite the importance of this interplay, basic understanding of the role of biogeochemical interfaces for microbial performance is still missing. We postulate that biogeochemical interfaces in soil are important for the formation of functional consortia of microorganisms, which are able to shape their own microenvironment and therefore influence the properties of interfaces in soil. Furthermore biogeochemical interfaces act as genetic memory of soils, as they can store DNA from dead microbes and protect it from degradation. We propose that for the formation of functional biogeochemical interfaces microbial dispersal (e.g. along fungal networks) in response to quality and quantity of bioavailable carbon and/or water availability plays a major role, as the development of functional guilds of microbes requires energy and depends on the redox state of the habitat.To address these questions, hexadecane degradation will be studied in differently developed artificial and natural soils. To answer the question on the role of carbon quantity and quality, experiments will be performed with and without litter material at different water contents of the soil. Experiments will be performed with intact soil columns as well as soil samples where the developed interface structure has been artificially destroyed. Molecular analysis of hexadecane degrading microbial communties will be done in vitro as well as in situ. The corresponding toolbox has been successfully developed in the first phase of the priority program including methods for genome, transcriptome and proteome analysis.

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

Das Projekt "Development of an integrated forest carbon monitoring system with field sampling and remote sensing for tropical forests in Indonesia" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Göttingen, Burckhardt-Institut, Abteilung Waldinventur und Fernerkundung.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.

Late-Glacial and Holocene vegetational stability of southern South America

Das Projekt "Late-Glacial and Holocene vegetational stability of southern South America" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Göttingen, Albrecht-von-Haller-Institut für Pflanzenwissenschaften, Abteilung für Palynologie und Klimadynamik.This project focuses on the long-term stability (or otherwise) of vegetation, based on a series of multi-proxy records in southern South America. We will build a network of sites suitable for high-resolution reconstructions of changes in vegetation since the Last Glacial Maximum, and use these to test a null hypothesis that changes in vegetation over the past 14,000 years are driven by internal dynamics rather than external forcing factors. The extent to which the null hypothesis can be falsified will reveal the degree to which we can expect to be able to predict how vegetation is affected by external events, including future climate change. The southern fringes of the South American landmass provide a rare opportunity to examine the development of moorland vegetation with sparse tree cover in a wet, cool temperate climate of the Southern Hemisphere. We present a record of changes in vegetation over the past 17,000 years, from a lake in extreme southern Chile (Isla Santa Inés, Magallanes region, 53°38.97S; 72°25.24W; Fontana, Bennett 2012: The Holocene), where human influence on vegetation is negligible. The western archipelago of Tierra del Fuego remained treeless for most of the Lateglacial period. Nothofagus may have survived the last glacial maximum at the eastern edge of the Magellan glaciers from where it spread southwestwards and established in the region at around 10,500 cal. yr BP. Nothofagus antarctica was likely the earlier colonizing tree in the western islands, followed shortly after by Nothofagus betuloides. At 9000 cal. yr BP moorland communities expanded at the expense of Nothofagus woodland. Simultaneously, Nothofagus species shifted to dominance of the evergreen Nothofagus betuloides and the Magellanic rain forest established in the region. Rapid and drastic vegetation changes occurred at 5200 cal. yr BP, after the Mt Burney MB2 eruption, including the expansion and establishment of Pilgerodendron uviferum and the development of mixed Nothofagus-Pilgerodendron-Drimys woodland. Scattered populations of Nothofagus, as they occur today in westernmost Tierra del Fuego may be a good analogue for Nothofagus populations during the Lateglacial in eastern sites. Climate, dispersal barriers and/or fire disturbance may have played a role controlling the postglacial spread of Nothofagus. Climate change during the Lateglacial and early Holocene was a prerequisite for the expansion of Nothofagus populations and may have controlled it at many sites in Tierra del Fuego. The delayed arrival at the site, with respect to the Holocene warming, may be due to dispersal barriers and/or fire disturbance at eastern sites, reducing the size of the source populations. The retreat of Nothofagus woodland after 9000 cal. yr BP may be due to competitive interactions with bog communities. Volcanic disturbance had a positive influence on the expansion of Pilgerodendron uviferum and facilitated the development of mixed Nothofagus-Pilgerodendron-Drimys woodland.

Omongwa Pan, Namibia (June 2015) - an EnMAP Preparatory Flight Campaign

WTZ Südliches Afrika SPACES: GeoArchives II - Signale des Klima- und Landschaftswandels konserviert in Geoarchives des südlichen Afrika, Vorhaben: Hänge, Schwemmfächer und Flussterrassen als Geoarchive; Rekonstruktion der Paläoumwelt- und Paläoklimasignale (SP2; SP4)

Das Projekt "WTZ Südliches Afrika SPACES: GeoArchives II - Signale des Klima- und Landschaftswandels konserviert in Geoarchives des südlichen Afrika, Vorhaben: Hänge, Schwemmfächer und Flussterrassen als Geoarchive; Rekonstruktion der Paläoumwelt- und Paläoklimasignale (SP2; SP4)" wird/wurde gefördert durch: Bundesministerium für Bildung und Forschung. Es wird/wurde ausgeführt durch: Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum.1. Vorhabenziel: Die Untersuchung von mikrobiellen Gemeinschaften in Salzpfannen im südwestlichen Afrika über die Zeit birgt das Potential, wertvolle Informationen über die mit den Mikroorganismen assoziierten Klima- und Umweltbedingungen der Vergangenheit zu erhalten. In der GeoArchives II Phase wollen wir neue mikrobiologische Ansätze und Methoden anwenden, um die Änderungen der mikrobiellen Gemeinschaften mit der Zeit zu dokumentieren (Kultivierungsexperimente von Schlüsselorganismen, externe DNA als Schlüssel zur Vergangenheit), die gewonnenen Daten mit biogeochemischen Methoden (mikrobielle Biomarker) zu validieren und Klimainformationen aus den Daten abzuleiten. Außerdem wollen wir die Wechselwirkung von Mikroorganismen mit Gesteinsoberflächen im Zuge von bodenbildenden Verwitterungsprozessen in der Region untersuchen. Weiterhin sollen mit Hilfe geochronologischer Datierungsansätze relevante Landschaftsformen (Salzpfannen, Hänge, Schwemmfächer und Terrassen) in ihrer Genese datiert werden, um aktuelle Fragen nach den Auswirkungen des Klima- und Nutzungswandels auf die heutigen Landschaftsökosysteme zu beantworten. 2. Arbeitsplanung: Im Projekt sollen zwei Probenahmen durchgeführt werden. Die Salzpfannen werden Ende 2016 Gegenstand der ersten Kampagne sein. Die Salzpfannenproben sollen für die Kultivierungsexperimente und die Studien zur extrazellularen DNA verwendet werden. In der zweiten Kampagne soll im Frühjahr 2017 im Tsauchab-Tal Material für die Untersuchung der Verwitterungsprozesse gewonnen werden. Des Weiteren sollen Altersdatierung von Hangsedimenten, Schwemmfächern, Flussterrassen und Talbodenverschüttungen vorgenommen werden, um die Stabilität und das Potenzial dieser Flächen für die Landnutzung unter dem Einfluss des Klimawandels zu bewerten.

WTZ Südliches Afrika SPACES: GeoArchives II - Signale des Klima- und Landschaftswandels konserviert in Geoarchives des südlichen Afrika, Vorhaben: Molekulare Paläoklimatologie

Das Projekt "WTZ Südliches Afrika SPACES: GeoArchives II - Signale des Klima- und Landschaftswandels konserviert in Geoarchives des südlichen Afrika, Vorhaben: Molekulare Paläoklimatologie" wird/wurde gefördert durch: Bundesministerium für Bildung und Forschung. Es wird/wurde ausgeführt durch: Carl von Ossietzky Universität Oldenburg, Institut für Chemie und Biologie des Meeres.

WTZ Südliches Afrika SPACES: GeoArchives II - Signale des Klima- und Landschaftswandels konserviert in Geoarchives des südlichen Afrika, Vorhaben: Rekonstruktion holozäner Umwelt- und Klimaschwankungen

Das Projekt "WTZ Südliches Afrika SPACES: GeoArchives II - Signale des Klima- und Landschaftswandels konserviert in Geoarchives des südlichen Afrika, Vorhaben: Rekonstruktion holozäner Umwelt- und Klimaschwankungen" wird/wurde gefördert durch: Bundesministerium für Bildung und Forschung. Es wird/wurde ausgeführt durch: Senckenberg Gesellschaft für Naturforschung, Senckenberg am Meer, Abteilung Meeresforschung.

Energy and Water Fluxes at the Soil Atmosphere Interface of Water Repellent soils

Das Projekt "Energy and Water Fluxes at the Soil Atmosphere Interface of Water Repellent soils" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Technische Universität Berlin, Institut für Ökologie, Fachgebiet Bodenkunde.Water repellency (WR) plays a significant role in a large number of soils all over the world. In many regions global warming will lead to drier land surfaces and thus, increasing the likeliness of actual water repellency for such soils. The hydrological effects of WR (surface runoff, water erosion, preferential flow) have been relatively well investigated in the last decades. However, its effect on the energy balance between soil and atmosphere has not been studied yet. We postulate that global warming does not only lead to an increase in WR of soils, but WR has an impact on the energy balance and thus, will lead to a feedback on global warming. In order to test our hypothesis, we want to determine all components of the energy- and water balance between soil and atmosphere for a strongly water repellent soil. As a reference we want to repeat the same measurements for the same soil, at which the WR has been suspended by application of a surfactants. While the laboratory studies aim to give insight into more principle processes, the lysimeter (bare and with plants) and field scale studies shall give information about integrated complex natural processes. The gained knowledge shall be implemented into a numerical simulation tool for modeling water and energy balances in order to predict the effects of WR under different atmospheric conditions and physical soil properties.

Steady-State Dilution and Mixing-Controlled Reactions in Three-Dimensional Heterogeneous Porous

Das Projekt "Steady-State Dilution and Mixing-Controlled Reactions in Three-Dimensional Heterogeneous Porous" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Eberhard Karls Universität Tübingen, Zentrum für Angewandte Geowissenschaften (ZAG), Arbeitsgruppe Hydrogeology.Understanding transport of contaminants is fundamental for the management of groundwater re-sources and the implementation of remedial strategies. In particular, mixing processes in saturated porous media play a pivotal role in determining the fate and transport of chemicals released in the subsurface. In fact, many abiotic and biological reactions in contaminated aquifers are limited by the availability of reaction partners. Under steady-state flow and transport conditions, dissolved reactants come into contact only through transverse mixing. In homogeneous porous media, transverse mixing is determined by diffusion and pore-scale dispersion, while in heterogeneous formations these local mixing processes are enhanced. Recent studies investigated the enhancement of transverse mixing due to the presence of heterogeneities in two-dimensional systems. Here, mixing enhancement can solely be attributed to flow focusing within high-permeability inclusions. In the proposed work, we will investigate mixing processes in three dimensions using high-resolution laboratory bench-scale experiments and advanced modeling techniques. The objective of the proposed research is to quantitatively assess how 3-D heterogeneity and anisotropy of hydraulic conductivity affect mixing processes via (i) flow focusing and de-focusing, (ii) increase of the plume surface, (iii) twisting and intertwining of streamlines and (iv) compound-specific diffusive/dispersive properties of the solute species undergoing transport. The results of the experimental and modeling investigation will allow us to identify effective large-scale parameters useful for a correct description of conservative and reactive mixing at field scales allowing to explain discrepancies between field observations, bench-scale experiments and current stochastic theory.

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