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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)

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.

Late-Glacial and Holocene vegetational stability of southern South America

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.

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.

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.

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)

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.

Study of adsorption-based carbon dioxide capture and storage systems under wet conditions

In order to be able to sustainably use fossil fuels as an energy source, various techniques are being considered to capture the carbon dioxide produced in combustion and sequester it or otherwise prevent it from being released into the atmosphere. Several of these techniques involve the adsorption of gases, especially CO2, to adsorbent solid materials, either as a means of separating gases from each other, or as a storage mechanism (e.g. in coal seams). In all cases of interest, moisture is present, affecting the adsorption of gases in ways that are not fully understood yet. This project will study the interaction of CO2 and the other gases involved (nitrogen, hydrogen, methane depending on the specific application) with different adsorbents in the presence of water. Adsorption plays a role in the capture of carbon dioxide as a technique to separate the greenhouse gas from other gases. This can be done in pre-combustion capture, where the CO2 has to be separated from hydrogen, usually by pressure swing adsorption (PSA) on activated carbon or zeolites; or it can be done by post-combustion capture, where the CO2 is separated from the rest of the flue gas, mainly nitrogen. This is typically done by temperature swing adsorption (TSA) on activated carbon. Another application involves adsorption as a way of extracting carbon dioxide directly from ambient air In the area of carbon dioxide storage, adsorption is significant when the carbon dioxide is to be used for enhanced coal bed methane recovery (ECBM). In this application, CO2 is injected into coal seams as a displacer for methane adsorbed into the pores in the coal. This is an attractive option to store CO2, as it enhances methane production at the same time. The capacity of coal for carbon dioxide has consistently been higher for carbon dioxide than for methane, leading to a net storage of carbon dioxide. Both systems for CO2 capture and for storage have been the subjects of study, but the effect that water has on these systems has yet to be investigated in detail. The scientific questions that are to be addressed with this project are (1) how to characterize the role of water on CO2 adsorption, (2) how to understand and describe it, and (3) how to use this knowledge to overcome or to exploit the effect of water in order to design better separation processes.

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

The dataset is composed of Neo HySpex (VNIR/SWIR) hyperspectral imagery acquired during airplane overflights on June 6th, 2015 covering the Omongwa Pan located in the South-West Kalahari, Namibia. The dataset includes three cloud-free flight lines with 408 spectral bands ranging from VNIR to SWIR wavelength regions (0.4-2.5 µm). The dataset also includes Level 2A EnMAP-like imagery simulated using the end-to-end Simulation tool (EeteS). The overall goal of the campaign was to acquire imagery over the Omongwa Pan and use the spectral reflectance for the analyses of surface sediments, specifically the mineralogical composition of exposed surface evaporites / salts on the airborne and spaceborne scale. The data are highly novel and can be used to test estimation of surface sediment properties in a highly saline and dynamic environment.

Developmental neurotoxicity assessment of mixtures in children (DENAMIC)

Objective: Various recent epidemiological studies have indicated that exposure to low doses of environmental biologically active contaminants during human development can alter gene expression and have deleterious effects on cognitive development in childhood. The DENAMIC project is ultimately focused on reducing such effects of environmental contamination on learning and developmental disorders in children. It aims to study and evaluate environment-health relationships in children. Key elements are: development of sophisticated tools and methods for early warning and screening of compounds for neurotoxicity, to study mechanisms of disease development and the role of individual susceptibility, to improve assessment of exposures and effects, focus on combined exposures to environmental agents that can interact to enhance adverse effects and reduction of health inequalities of children through Europe. One of the main aims of DENAMIC is to develop tools and methods for neurotoxic effects of mixtures of environmental pollutants at low levels, possibly resulting in (subclinical) effects on learning (cognitive skills) and developmental disorders in children (e.g ADHD, autism spectrum disorders and anxiety disorders). A broad suite of contaminants will be included in the studies, with options to bring in new chemicals in case evidence comes up during the project. With 14 partners from ten different countries DENAMIC has a true international character. It is a comprehensive, multi-disciplinary project. Six SME's will play a key role in the development of biotechnological screening tools. The most modern techniques in the fields of genomics, proteomics, metabolomics and transcriptomics will be applied. Dissemination will ensure the project results to arrive at policymakers' desks, and will also illustrate the subject for a scientific audience and the public. The very large network of the consortium ensures dissemination to European industries, and every other interested stakeholder.

Assessment of satellite constellations for monitoring the variations in earth s gravity field

More than a decade has passed since the launch of the GRACE satellite mission. Although designed for a nominal mission lifetime of 5 years, it still provides valuable science data. An eventual systems failure and, thus, mission termination is expected any time soon, though. Despite a relative low spatial and temporal resolution, the monthly gravity fields have proved an invaluable and novel parameter set in several geoscience disciplines, allowing new research venues in the study of Global Change phenomena. The hydrological cycle is now subject to quantification at continental scales; the state of the cryosphere, particularly ice sheet melting over Greenland and Antarctica, can be monitored; and steric effects of sea-level change have become separable from non-steric ones. The enormous success of the mission has driven the need for continuation of monitoring mass changes in the Earth system. Indeed, a GRACE Follow-On (GFO) mission has been approved for launch in August 2017. Like its predecessor it will consist of two satellites flying en echelon with intersatellite K-Band ranging as the main gravitational sensor. Despite a number of planned technological improvements, including a laser link as demonstrator, GFO will mostly be based on GRACE heritage. Given a similar orbit configuration and a similar systems setup, the quality of eventual gravity field products can be expected to be in the same range as the current GRACE products. To guarantee the continuation of such successful gravity field time series ESA has embarked several years ago on a long term strategy for future gravity field satellite missions, both in terms of technology development and in terms of consolidating the user community. Scientists from academia and industry held a workshop on The Future of Satellite Gravimetry at ESTEC premises, 12-13 April 2007, (RD-9). Similar workshops have been organized by other organizations, e.g. the joint GGOS/IGCP565 workshop Towards a Roadmap for Future Satellite Gravity Missions in Graz, September 30 - October 2, 2009. ESA furthermore played a key role in consolidating the international user community by funding a series of study projects, cf. (RD-1) to (RD-5). Similar projects have been funded and conducted at national level, e.g. the German BMBF-funded Geotechnologies III project Concepts for future gravity field satellite missions (PI: N. Sneeuw). These studies, together with GRACE experience, have provided a clear understanding of the current limitations of a GRACE-type mission. In particular the limitations in sampling and sensitivity of a single pair of satellites with in-orbit in-line sensitivity are well documented. At the same time, these studies have shown the design options and a roadmap towards a next generation gravity field mission.

Antagonism in the mycorrhizal symbiosis - a search for mechanisms

Lead: Plant growth responses to arbuscular mycorrhizal fungi (AMF) are highly variable, ranging from mutualism in a wide range of plants, to antagonism in some non-mycorrhizal plant species and plants characteristic of disturbed environments. This project focuses on a number of potential mechanisms that can explain why AMF suppress growth of some plant species. Background: Arbuscular mycorrhizal fungi (AMF) play a key role in ecosystems by influencing plant growth and ecosystem functioning. Most studies have focused on the positive effects of AMF on plant growth and nutrition. However, plant growth responses to arbuscular mycorrhizal fungi (AMF) are highly variable, ranging from mutualism in a wide range of plants, to antagonism in some non-mycorrhizal plant species and plants characteristic of disturbed environments. The precise mechanisms responsible for the negative effects of AMF on some plants received almost no attention as most research focused on the positive effects of AMF on plant growth. This project focuses on a number of potential mechanisms that can explain why AMF suppress growth of some plant species. Aims: The following key hypothesis are investigated in this project: 1. The cost-benefit relationship with AMF varies among plant species. Plants that respond negatively to AM fungi invest carbon into AMF, without benefit (nutrients) in return. 2. Plants that respond negatively to AM fungi invest carbon in mycorrhizal networks while coexisting plant species receive the benefit of such networks. 3. AM fungi suppress growth of some plants by exuding allelopathic compounds. 4. Plants that respond negatively to AM fungi cannot block colonization by AM fungi under conditions in which AM fungi are unfavorable. Relevance: Recent studies have provided important insights into the role of AM fungi in ecosystems. These soil fungi can stimulate plant diversity and productivity and enhance stress resistance in a wide range of plants. Until now, research largely focused on the positive effects of AM fungi on plant growth, ignoring that an estimated 17'000 - 39'000 species are non-mycorrhizal, including a large number of weeds. A few recent studies suggest that many non-mycorrhizal plants may be suppressed by AM fungi. Moreover, the fact that some mycorrhizal plants also respond negatively to AM fungi points to surprising interactions in the rhizosphere. AM fungi may exude allelopathic compounds with suppressive effects on plants, including a number of weeds. The findings of this project will be highly relevant for sustainable agricultural production. Moreover, the study will lead to a better understanding of plant-microbe interactions, mycorrhizal and soil ecology, and crop-weed interactions, and will stimulate our understanding of the role that microbes play in the soil.

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