Sediment erosion and transport is critical to the ecological and commercial health of aquatic habitats from watershed to sea. There is now a consensus that microorganisms inhabiting the system mediate the erosive response of natural sediments ('ecosystem engineers') along with physicochemical properties. The biological mechanism is through secretion of a microbial organic glue (EPS: extracellular polymeric substances) that enhances binding forces between sediment grains to impact sediment stability and post-entrainment flocculation. The proposed work will elucidate the functional capability of heterotrophic bacteria, cyanobacteria and eukaryotic microalgae for mediating freshwater sediments to influence sediment erosion and transport. The potential and relevance of natural biofilms to provide this important 'ecosystem service' will be investigated for different niches in a freshwater habitat. Thereby, variations of the EPS 'quality' and 'quantity' to influence cohesion within sediments and flocs will be related to shifts in biofilm composition, sediment characteristics (e.g. organic background) and varying abiotic conditions (e.g. light, hydrodynamic regime) in the water body. Thus, the proposed interdisciplinary work will contribute to a conceptual understanding of microbial sediment engineering that represents an important ecosystem function in freshwater habitats. The research has wide implications for the water framework directive and sediment management strategies.
It has been suggested that dying and decaying fine roots and root exudation represent important, if not the most important, sources of soil organic carbon (SOC) in forest soils. This may be especially true for deep-reaching roots in the subsoil, but precise data to prove this assumption are lacking. This subproject (1) examines the distribution and abundance of fine roots (greater than 2 mm diameter) and coarse roots (greater than 2 mm) in the subsoil to 240 cm depth of the three subsoil observatories in a mature European beech (Fagus sylvatica) stand, (2) quantifies the turnover of beech fine roots by direct observation (mini-rhizotron approach), (3) measures the decomposition of dead fine root mass in different soil depths, and (4) quantifies root exudation and the N-uptake potential with novel techniques under in situ conditions with the aim (i) to quantify the C flux to the SOC pool upon root death in the subsoil, (ii) to obtain a quantitative estimate of root exudation in the subsoil, and (iii) to assess the uptake activity of fine roots in the subsoil as compared to roots in the topsoil. Key methods applied are (a) the microscopic distinction between live and dead fine root mass, (b) the estimation of fine and coarse root age by the 14C bomb approach and annual ring counting in roots, (c) the direct observation of the formation and disappearance of fine roots in rhizotron tubes by sequential root imaging (CI-600 system, CID) and the calculation of root turnover, (d) the measurement of root litter decomposition using litter bags under field and controlled laboratory conditions, (e) the estimation of root N-uptake capacity by exposing intact fine roots to 15NH4+ and 15NO3- solutions, and (f) the measurement of root exudation by exposing intact fine root branches to trap solutions in cuvettes in the field and analysing for carbohydrates and amino acids by HPLC and Py-FIMS (cooperation with Prof. A. Fischer, University of Trier). The obtained data will be analysed for differences in root abundance and activity between subsoil (100-200 cm) and topsoil (0-20 cm) and will be related to soil chemical and soil biological data collected by the partner projects that may control root turnover and exudation in the subsoil. In a supplementary study, fine root biomass distribution and root turnover will also be studied at the four additional beech sites for examining root-borne C fluxes in the subsoil of beech forests under contrasting soil conditions of different geological substrates (Triassic limestone and sandstone, Quaternary sand and loess deposits).
The CHAMP mission provided a great amount of geomagnetic data all over the globe from 2000 to 2010. Its dense data coverage has allowed us to build GRIMM - GFZ Reference Internal Magnetic Model - which has the highest ever resolution for the core field in both space and time. We have already modeled the fluid flow in the Earth's outer core by applying the diffusionless magnetic induction equation to the latest version of GRIMM, to find that the flow evolves on subdecadal timescales, with a remarkable correlation to the observed fluctuation of Earth rotation. These flow models corroborated the presence of six-year torsional oscillations in the outer core fluid. Torsional oscillation (TO) is a type of hydromagnetic wave, theoretically considered to form the most important element of decadal or subdecadal core dynamics. It consists of relative azimuthal rotations of rigid fluid annuli coaxial with the mantle's rotation and dynamically coupled with the mantle and inner core. In preceding works, the TOs have been studied by numerical simulations, either with full numerical dynamos, or solving eigenvalue problems ideally representing the TO system. While these studies drew insights about dynamical aspects of the modeled TOs, they did not directly take into account the observations of geomagnetic field and Earth rotation. Particularly, there have been no observation-based studies for the TO using satellite magnetic data or models. In the proposed project, we aim at revealing the subdecadal dynamics and energetics of the Earth's core-mantle system on the basis of satellite magnetic observations. To that end, we will carry out four work packages (1) to (4), for all of which we use GRIMM. (1) We perform timeseries analyses of core field and flow models, to carefully extract the signals from TOs at different latitudes. (2) We refine the conventional flow modeling scheme by parameterizing the magnetic diffusion at the core surface. Here, the diffusion term is reinstated in the magnetic induction equation, which is dynamically constrained by relating it to the Lorentz term in the Navier-stokes equation. (3) We develop a method to compute the electromagnetic core-mantle coupling torque on the core fluid annuli, whereby the energy dissipation due to the Joule heating is evaluated for each annulus. This analysis would provide insights on whether the Earth's TOs are free or forced oscillations. (4) Bringing together physical implications and computational tools obtained by (1) to (3), we finally construct a dynamical model for the Earth's TOs and core-mantle coupling such that they are consistent with GRIMM and Earth rotation observation. This modeling is unique in that the force balances concerning the TOs are investigated in time domain, as well as that the modeling also aims at improving the observation-based core flow model by considering the core dynamics.
Chlorinated ethylenes are prevalent groundwater contaminants. Numerous studies have addressed the mechanism of their reductive dehalogenation during biodegradation and reaction with zero-valent iron. However, despite insight with purified enzymes and well-characterized chemical model systems, conclusive evidence has been missing that the same mechanisms do indeed prevail in real-world transformations. While dual kinetic isotope effect measurements can provide such lines of evidence, until now this approach has not been possible for chlorinated ethylenes because an adequate method for continuous flow compound specific chlorine isotope analysis has been missing. This study attempts to close this prevalent research gap by a combination of two complementary approaches. (1) A novel analytical method to measure isotope effects for carbon and chlorine. (2) A carefully chosen set of well-defined model reactants representing distinct dehalogenation mechanisms believed to be important in real-world systems. Isotope trends observed in biotic and abiotic environmental dehalogenation will be compared to these model reactions, and the respective mechanistic hypotheses will be confirmed or discarded. With this hypothesis-driven approach it is our goal to elucidate for the first timdehalogenation reactions.
BACKGROUND: The Kingdom of Jordan belongs to the ten water scarcest countries in the world, and climate change is likely to increase the frequency of future droughts. Jordan is considered among the 10 most water impoverished countries in the world, with per capita water availability estimated at 170 m per annum, compared to an average of 1,000 m per annum in other countries. Jordan Government has taken the strategic decision to develop a conveyor system including a 325 km pipe to pump 100 million cubic meters per year of potable water from Disi-Mudawwara close to the Saudi Border in the south, to the Greater Amman area in the north. The construction of the water pipeline has started end of 2009 and shall be finished in 2013. Later on, the pipeline could serve as a major part of a national water carrier in order to convey desalinated water from the Red Sea to the economically most important central region of the country. The conveyor project will not only significantly increase water supplies to the capital, but also provide for the re-allocation of current supplies to other governorates, and for the conservation of aquifers. In the context of the Disi project that is co-funded by EIB two Environmental and Social Management Plans have been prepared: one for the private project partners and one for the Jordan Government. The latter includes the Governments obligation to re-balance water allocations to irrigation and to gradually restore the protected wetlands of Azraq (Ramsar site) east of Amman that has been depleted due to over-abstraction by re-directing discharge of highland aquifers after the Disi pipeline becomes operational. The Water Strategy recognizes that groundwater extraction for irrigation is beyond acceptable limits. Since the source is finite and priority should be given to human consumption it proposes to tackle the demand for irrigation through tariff adjustments, improved irrigation technology and disincentive to water intensive crops. The Disi aquifer is currently used for irrigation by farms producing all kinds of fruits and vegetables on a large scale and exporting most of their products to the Saudi and European markets and it is almost a third of Jordan's total consumption. The licenses for that commercial irrigation were finished by 2011/12. Whilst the licenses will be not renewed the difficulty will be the enforcement and satellite based information become an important supporting tool for monitoring. OUTLOOK: The ESA funded project Water management had the objective to support the South-North conveyor project and the activities of EIB together with the MWI in Jordan to ensure the supply of water for the increasing demand. EO Information provides a baseline for land cover and elevation and support the monitoring of further stages. usw.
Cherry leaf roll virus (CLRV) is a plant pathogen of economic and ecologic importance. It is globally distributed in a wide range of forest, fruit, and ornamental trees and shrubs. In several areas of cherry and walnut production CLRV causes severe losses in yield and quality. With current reference to the rapid dissemination and strong symptom expression in Finnish birches and the Germany-wide distribution of CLRV in birches and elderberry, we continuously investigate and gradually reveal CLRV transmission pathways as by pollen, seeds or water. However, modes and interactions responsible for the wide intergeneric host transmission as well as for the exceptional CLRV epidemic in Fennoscandia still remain unknown. In this project systematic studies shall investigate biological vectors as a causal agent to finally derive control mechanisms and strategies to avoid new epidemics in different hosts and geographic regions. Detailed monitoring of the invertebrate fauna of birch stands/forests and elderberry plantations in Germany and Finland shall reveal potential vectors to subsequently study them in detail by approved virus detection methods and transmission experiments. Molecular analyses of the CLRV coat protein shall prove its role as a viral determinant for a virus/vector interaction. Consequently, this project essentially will contribute important answers on the CLRV epidemiology, and this will be a key element within the first network of research on plant viral pathogens in forest trees.
Im letzten Jahrzehnt war der grönländische Eisschild mehreren Extremereignissen ausgesetzt, mit teils unerwartet starken Auswirkungen auf die Oberflächenmassebilanz und den Eisfluss, insbesondere in den Jahren 2010, 2012 und 2015. Einige dieser Schmelzereignisse prägten sich eher lokal aus (wie in 2015), während andere fast die gesamte Eisfläche bedeckten (wie in 2010).Mit fortschreitendem Klimawandel ist zu erwarten, dass extreme Schmelzereignisse häufiger auftreten und sich verstärken bzw. länger anhalten. Bisherige Projektionen des Eisverlustes von Grönland basieren jedoch typischerweise auf Szenarien, die nur allmähliche Veränderungen des Klimas berücksichtigen, z.B. in den Representative Concentration Pathways (RCPs), wie sie im letzten IPCC-Bericht genutzt wurden. In aktuellen Projektionen werden extreme Schmelzereignisse im Allgemeinen unterschätzt - und welche Konsequenzen dies für den zukünftigen Meeresspiegelanstieg hat, bleibt eine offene Forschungsfrage.Ziel des vorgeschlagenen Projektes ist es, die Auswirkungen extremer Schmelzereignisse auf die zukünftige Entwicklung des grönländischen Eisschildes zu untersuchen. Dabei werden die unmittelbaren und dauerhaften Auswirkungen auf die Oberflächenmassenbilanz und die Eisdynamik bestimmt und somit die Beiträge zum Meeresspiegelanstieg quantifiziert. In dem Forschungsprojekt planen wir zudem, kritische Schwellenwerte in der Häufigkeit, Intensität sowie Dauer von Extremereignissen zu identifizieren, die - sobald sie einmal überschritten sind - eine großräumige Änderung in der Eisdynamik auslösen könnten.Zu diesem Zweck werden wir die dynamische Reaktion des grönländischen Eisschilds in einer Reihe von Klimaszenarien untersuchen, in denen extreme Schmelzereignisse mit unterschiedlicher Wahrscheinlichkeit zu bestimmten Zeitpunkten auftreten, und die Dauer und Stärke prognostisch variiert werden. Um indirekte Effekte durch verstärktes submarines Schmelzen hierbei berücksichtigen zu können, werden wir das etablierte Parallel Ice Sheet Model (PISM) mit dem Linearen Plume-Modell (LPM) koppeln. Das LPM berechnet das turbulente submarine Schmelzen aufgrund von Veränderungen der Meerestemperatur und des subglazialen Ausflusses. Es ist numerisch sehr effizient, so dass das gekoppelte PISM-LPM Modell Ensemble-Läufe mit hoher Auflösung ermöglicht. Folglich kann eine breite Palette von Modellparametern und Klimaszenarien in Zukunftsprojektionen in Betracht gezogen werden.Mit dem interaktiv gekoppelten Modell PISM-LPM werden wir den Beitrag Grönlands zum Meeresspiegelanstieg im 21. Jahrhundert bestimmen, unter Berücksichtigung regionaler Veränderungen von Niederschlag, Oberflächen- und Meerestemperaturen, und insbesondere der Auswirkungen von Extremereignissen. Ein Hauptergebnis wird eine Risikokarte sein, die aufzeigt, in welchen kritischen Regionen Grönlands zukünftige extreme Schmelzereignisse den stärksten Eisverlust zur Folge hätten.
Soil structure determines a large part of the spatial heterogeneity in water storage and fluxes from the plot to the hillslope scale. In recent decades important progress in hydrological research has been achieved by including soil structure in hydrological models. One of the main problems herein remains the difficulty of measuring soil structure and quantifying its influence on hydrological processes. As soil structure is very often of biogenic origin (macropores), the main objective of this project is to use the influence of bioactivity and resulting soil structures to describe and support modelling of hydrological processes at different scales. Therefore, local scale bioactivity will be linked to local infiltration patterns under varying catchment conditions. At hillslope scale, the spatial distribution of bioactivity patterns will be linked to connectivity of subsurface structures to explain subsurface stormflow generation. Then we will apply species distribution modelling of key organisms in order to extrapolate the gained knowledge to the catchment scale. As on one hand, bioactivity influences the hydrological processes, but on the other hand the species distribution also depends on soil moisture contents, including the feedbacks between bioactivity and soil hydrology is pivotal for getting reliable predictions of catchment scale hydrological behavior under land use change and climate change.
Recent discussions on the path eco-hydromorphic research has followed in the past decades highlight the need for greater ecological input into this field. Traditional approaches have been criticized for being largely correlation-based (Vaughan et al., 2009) ecological black boxes (Leclerc, 2005) and strongly relying on weak, disproven and/or outdated assumptions about the dynamics of stream biota (Lancaster & Downes, 2010). In recognition of this, process-oriented research aiming at elucidating and quantifying causal mechanisms has been proposed as a promising approach, though challenging, to study the relations between flow, morphodynamics and biological populations in running waters. In terms of levels of biological organization, it has been recognized that processes determining the response of aquatic biota to hydromorphological alteration occur mainly at the population level. In this sense, relating demographic rates to flow and morphology seems to offer great potential for progress (Lancaster & Downes, 2010). Thus, tapping into existing ecological knowledge (e.g., key patch approach for habitat networks, Verboom et al. 2001; metapopulation theory, Levins 1970; Hanski & Gaggiotti 2004, landscape-scale estimations of habitat suitability and carrying capacity, Reijnen et al. 1995; Duel et al. 1995 2003; population-level viability estimations; Akçakaya 2001; resource utilization scales, ONeill et al. 1988; habitat-use patterns, Milne et al. 1989) in order to link ecology to hydromorphology at a more fundamental level constitutes an important path towards better science and management.
Organische Aerosole (OA) sind wichtige Bestandteile atmosphärischer Partikel. Je nach Region können sie zwischen 20 und 90% der gesamten Submikron-Partikelmasse betragen. Dennoch sind organische Aerosolquellen, atmosphärische Prozesse und Ableitung sehr ungewiss. Vorrangiges Ziel dieses Antrages ist es, die Auswirkungen organischer Aerosole auf Luftqualität und Klima zu untersuchen. Dazu soll die Darstellung des Aerosolaufbaus und die Weiterentwicklung in einem globalen Klima-Chemie-Modell verbessert werden. Das geplante Vorhaben basiert auf einem rechnerisch effizienten Modul zur Beschreibung der Zusammensetzung und Entwicklung atmosphärischer Aerosole in der Atmosphäre (ORACLE), ein Teil des ECHAM5/MESSy (EMAC) Klima-Chemie-Modells. ORACLE wird unter Berücksichtigung aller auf Labor- und Feldmessungen basierenden neuesten Erkenntnissen und Entwicklungen aktualisiert werden, um den zunehmend oxidierenden, weniger flüchtigen und stärker hygroskopischen Charakter des organischen Aerosols während der atmosphärischen Alterung mittels Nachverfolgung ihrer beiden wichtigsten Parameter, Sättigungskonzentration und Sauerstoffgehalt, genauer darzustellen. Dieses Modellsystem soll eingesetzt werden, um die Unsicherheit hinsichtlich der Einflüsse organischer Aerosole auf die globale Luftqualität und den Strahlungsantrieb zu verringern, und zwar durch: i) Quantifizierung des relativen Beitrags der Bildung sekundärer organischer Aerosole (SOA) sowie Emissionen primärer organischer Aerosole (POA) auf den Gesamthaushalt organischer Aerosole in unterschiedlichen Umgebungen; ii) Quantifizierung des Beitrags von Biomasseverbrennung und Schadstoffemissionen sowie chemische Alterung und weiträumige Übertragung auf den Gesamthaushalt organischer Aerosole; iii) Ermittlung, inwieweit SOA Konzentrationen durch biogene und anthropogene Emissionen sowie photochemische Alterungsprozesse beeinträchtigt werden; iv) Untersuchung der Weiterentwicklung von SOA-Bildung aus natürlichen Quellen durch deren Interaktion mit anthropogenen Emissionen; v) Abschätzung der Auswirkungen photochemischer Alterungsprozesse auf die physikalisch-chemischen Eigenschaften organischer Aerosole (z.B. Hygroskopizität, Volatilität) und vi) Einschätzung der indirekten Auswirkungen organischer Aerosole auf das Klima. Vor allem aber wird der vorliegende Antrag der kommenden Generation von Chemie-Klimamodellen eine realistische Beschreibung der chemischen Entwicklung organischer Aerosole in der Atmosphäre liefern, was für die Reduzierung der Aerosol-Unsicherheiten in der Luftqualität und bei Klimasimulationen von wesentlicher Bedeutung ist. Es ist auch davon auszugehen, dass das Forschungsvorhaben wertvolle Informationen zu den Quellen und der Produktion von OA weltweit liefert, was derzeitige CCMs nicht leisten können und welche von Politikern zur Entwicklung zukünftiger wirksamer Emissionsminderungsstrategien genutzt werden können.
| Organisation | Count |
|---|---|
| Bund | 460 |
| Europa | 101 |
| Land | 2 |
| Wirtschaft | 1 |
| Wissenschaft | 217 |
| Zivilgesellschaft | 1 |
| Type | Count |
|---|---|
| Förderprogramm | 460 |
| License | Count |
|---|---|
| Offen | 460 |
| Language | Count |
|---|---|
| Deutsch | 85 |
| Englisch | 447 |
| Resource type | Count |
|---|---|
| Keine | 371 |
| Webseite | 89 |
| Topic | Count |
|---|---|
| Boden | 406 |
| Lebewesen und Lebensräume | 454 |
| Luft | 356 |
| Mensch und Umwelt | 460 |
| Wasser | 356 |
| Weitere | 460 |