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Human influences on forests in southern Ethiopia: the case of Shashemane-Munessa-forest

Especially during the last decades, the natural forests of Ethiopia have been heavily disturbed by human activities. Some forests have been totally cleared and converted into fields for agricultural use, other suffered from different influences, such as heavy grazing and selective logging. The ongoing research in the Shashemane-Munessa-study area (Gu 406/8-1,2) showed clearly that, in spite of interdiction and control, forests continue to be cleared and degraded. However, it is not yet sufficiently known, how and why these processes are still going on. Growing population pressure and economic constraints for the people living in and around the forests contribute to the actual situation but allow no final answers to the complex situation. Concerning a sustainable management of the forests there is to no solid basis for recommendations from the socioeconomic and socio-cultural view. Therefore, a comprehensive analysis of the traditional needs and forms of forest use, including all forest products, is necessary. The objective of this project is, to achieve this basis by carrying out intensive field observations, the consultation of aerial photographs, satellite imagery and above all semi-structured interviews with the population in the study area in order to contribute to the recommendations for a sustainable use of the Munessa Shasemane forests.

Schwerpunktprogramm (SPP) 1315: Biogeochemische Grenzflächen in Böden; Biogeochemical Interfaces in Soil, Importance of soil organic carbon and mineral particle size fractions for the fate of soil supplied organic chemicals and their microbial transformations

The biogeochemical interface (BGI) in this project is defined as the organo-mineral surface of soil particles colonized by microorganisms. In the preceding project it was demonstrated that the different soil particle size fractions were associated with specifically structured microbial communities, a characteristic amount of soil organic carbon, and a specific capacity for adsorption of the organic chemicals phenol and 2,4-dichlorophenol, respectively. While the diversity of the microbial community was responsive to fertilization-determined additional organic soil carbon in the larger particle size fractions, it was unaffected in clay. Stable isotope probing with 13C-labelled phenol and 2,4-dichlorophenol revealed that the soil organic carbon in the BGIs also affected the diversity of microorganisms involved in the degradation of these chemicals. All these results are yet only based on studying one soil with three organic carbon variants (Bad Lauchstädt) and only two organic compounds. The objective of this 2nd phase project is to apply the innovative technology developed in the 1st phase for studying the BGI processes with soil organic carbon variants from another soil (Ultuna, SPP 1315 site) and with the chiralic anilide Fungicide metalaxyl as an additional compound. This 2nd phase SPP 1315 project will also, in a collaborative effort with two other SPP 1315 partners, investigate (1) the importance of BGIs for the entantio-selective degradation of metalaxyl and (2) the role of soil microorganisms in the formation of bound residues, respectively. Furthermore, the project will utilize stable isotope probing and next-generation DNA sequencing to link the structural and functional diversity of the microbial communities responsible for metabolism of organic chemicals in the different BGIs determined by particle size fractions and soil organic carbon variants.

SP1.1 Dynamische Anreicherungsprozesse von organischer Substanz in der SML

Der Oberflächenfilm (SML) ist die oberste dünne Schicht des Ozeans und Teil jeglicher Wechselwirkung zwischen Luft und Meer, wie Gasaustausch, atmosphärische Deposition und Aerosolemission. Die Anreicherung von organischer Materie (OM) in der SML modifiziert die Luft-Meer-Austauschprozesse, aber welche OM-Komponenten selektiv angereichert werden, sowie warum und wann sie dies tun, ist weitgehend unbekannt (Engel et al., 2017). Unsere bisherige Forschung hat gezeigt, dass Biopolymere aus photoautotropher Produktion wichtige Komponenten der SML sind und den Luft-Meer-Austausch beeinflussen, indem sie als Biotenside (Galgani et al., 2016; Engel et al., 2018) und als Quelle primärer organischer Aerosole (Trueblood et al., 2021) wirken. Die Motivation unseres Projektes ist es daher, die dynamischen Anreicherungsprozesse von OM in der SML aufzuklären und zu beschreiben, wobei ein besonderer Schwerpunkt auf der Auflösung der OM-Quellen liegt. Mit unserem Modellierungsansatz ist es das Ziel, unser mechanistisches Verständnis der Zusammenhänge zwischen den Wachstumsbedingungen des Planktons, der Produktion und der Freisetzung von Biomolekülen, einschließlich potentieller Tenside, und der Akkumulation von OM in der SML zu konsolidieren. Eine solche Modellentwicklung wird in hohem Maße von den Ergebnissen und Erkenntnissen der verschiedenen Teilprojekte des BASS-Konsortiums profitieren. Umgekehrt ist es unsere Motivation, ein Modell zu etablieren, das als Synthesewerkzeug für die Interpretation und Integration von Feld-, Mesokosmen- und Labormessungen der OM-Anreicherung in der SML anwendbar wird.Relevanz für die Forschungsgruppe BASS - SP1.1 wird die Quellen, die Menge und die biochemische Zusammensetzung von OM in der SML entschlüsseln und damit wichtige Informationen für alle BASS-Teilprojekte liefern. Der primäre Ursprung von OM im Oberflächenozean ist die photosynthetische Produktion und die wichtigsten biochemischen Komponenten von frisch produzierter OM, d.h. Kohlenhydrate, Aminosäuren und Lipide, unterliegen der mikrobiellen Verarbeitung (SP1.2) und Photoreaktionen innerhalb der SML (SP1.3, SP1.4) und füllen auch den Pool der gelösten organischen Substanz (DOM) auf (SP1.5). Die Modellentwicklung in SP1.1 stellt eine Verbindung zwischen der Produktion von OM und ihrer Anreicherung innerhalb der SML her und zielt darauf ab, die entsprechenden Auswirkungen auf den Luft-Meer-Gasaustausch (SP2.1) zu bestimmen, indem Änderungen des Impulsflusses auf den Ozeanoberflächenschichten (SP2.2) sowie des Auftriebs (SP2.3) berücksichtigt werden. Das vorgeschlagene SML-Submodell wird auf der Grundlage der Ergebnisse aus SP1.4 und SP2.3 verfeinert. Ergebnisse aus den Modellsensitivitätsanalysen werden ergänzende Informationen über oberflächenaktive Eigenschaften verschiedener OM Komponenten und deren Auswirkungen auf Luft-Meer-Austauschprozesse liefern, die innerhalb von BASS ausgewertet werden.

H2020 Environment - EU Horizon 2020 Environment, Glass Recovering Revolution: High performance Optical Sorter for glass collection from Waste (SEEGLASS)

The amount of Municipal Solid Waste (MSW) in the EU28 reached 245 million tons in 2012. Nowadays, Europe directives for waste management are more restrictive each year (e.g Landfill Directive 1999/31/EC), but unfortunately, landfill disposal still represents 34% of total MSW generated. On the other hand, citizen awareness as well as the high fees operators pay for landfill disposal, have helped to greatly increase the percentage for recycling from 18% in 1995, to 42% in 2012. However, 40% of all the glass waste ends up in mixed MSW plants (which typically contain 7% of glass). Instead of being disposed of in selective-waste collection, it ends up in landfills or is composted/incinerated with the remnant waste. We have developed SEEGLASS, a high performance optical sorter based on computer vision and a pneumatic rejection system. Our aim is to solve this non-environmentally friendly problem, while also offering our end-users additional revenues with this recovered material, which is not being exploited now (49€/tn glass). In addition, extracting this glass, will allow the treatment plants to significantly reduce costs from waste disposal fees (50€/Tonne EU average and rising). Payback for customers is estimated in only 19 months. With this project we will (i) construct pre-conditioning process line, (ii) optimise our current SEEGLASS computer vision system as well as its mechanical and pneumatic design, to reach 80% glass recovery, with 99% purity, (iii) integrate both, the process line and the glass sorter solution into a demonstrator system, and (iv) validate its feasibility in-house with real MSW coming from different countries, as well as carry-out an 24/7 end-user validation. We, PICVISA, will be the first company to recover the glass fraction in refined MSW worldwide (the niche market exists worldwide) selling Turn-key installations or only SEEGLASS units, contributing to a disruptive change in the sector.

Selective tribological optimisation of fluid kinetics and efficiency by laser surface structuring (STOKES)

Economic losings caused by wear and friction are still tremendous, just in Germany the losings are amounted to 100 bn € p.a., for Europe the losses exceed 400 bn €. Recent investigations have shown that laser manufactured structures can exert considerable influence on the tribological behaviour of surfaces. Besides hydrodynamic effects, which can improve friction, the ability of the structures to store lubricant lead to the maintenance of a lubrication film. As the state of the art techniques for laser surface structuring, particularly for tribological applications are mainly on an a R&D level, the production technology is in need of adequate manufacturing techniques. Main topics in this field of research are the inevitable pre- and post-treatment steps of current laser surface structuring techniques as well as the high process durations. The overall goal of this project is to solve both of those tasks by the development and realisation of a process technology, which enables the process chain integrated laser surface structuring of hydraulic parts. The project aims to cover a defined segment of a growing market and the technological achievements will offer the participating SMEs promising options of upgrading their product values. In addition to the direct improvement of single systems by the investigations on demonstration parts within the project, the high transferability of the technique to further products will enable the value enhancement of whole product classes. This offers the possibility of a strong enhancement of the total product output. A consortium has been established, which covers the laser supply and technique as well as the surface preparation technology. Manufacturers of hydraulic parts are members of the consortium in order to close the technological range. Two powerful RTD performers could be gained, which are specialised on the laser processing on the one hand and on tribology on the other hand.

Stochastische Modellierung von Strömungs- und Transportprozessen im Untergrund, Stochastic modelling of subsurface flow and transport processes: Early-warning monitoring systems for improved drinking water resource protection

Subsurface flow and transport in uncertain heterogeneous porous media such as aquifers are poorly predictable for obvious reasons. In catchments of drinking water wells, this becomes even more complex, because it is even unknown when and where a contaminant might be released. Still, one needs to ensure the safety of supply with clean drinking water. This can be achieved with early warning systems, i.e., monitoring networks that pay special attention to the remaining time for action after a contamination has been detected somewhere in the aquifer. The goal of this project is to develop and establish a concept to assess, design and optimize early-warning systems within well catchments. Such optimal monitoring networks need to optimize and to balance three competing objectives: (1) a high detection probability, which can be reached by maximizing the field of vision of the monitoring network or by monitoring close to the drinking water well, (2) a long early-warning time such that there is enough time left to install counter measures after first detection, (3) the overall operating costs, which should ideally be reduced to a minimum. The early warning time describes the remaining travel time for contaminants to the drinking water well after they have been detected in a monitoring well. The detection probability of a contamination can only be assessed correctly, if the actual dilution, the spreading, and the large-scale uncertainty of the centroid position of the contaminant are not merged in the involved transport simulation. With this method, the safety level of existing monitoring systems can be assessed and set in relation to their operation costs. Also, selective improvements can be added to existing monitoring networks to increase the safety quality at minimal costs. Another application of this method is to design new optimal monitoring networks considering the different objective functions within multi-objective optimization. The method will be based on numerical simulation of flow and transport in heterogeneous porous media coupled with geostatistics and Monte-Carlo, wrapped up within the framework of an information-theoretic analysis and formal multi-objective optimization.

Evolutionary Conflicts and their Impact on Speciation, Evolutionary Conflicts and their Impact on Speciation (follow-up)

In addition to recognizing natural selection as a universal mechanism in evolution, Darwin also saw the importance of sexual selection, yet the two have been traditionally treated largely in isolation. Here I propose to apply experimental evolution (exposing experimental populations to controlled specific selective pressures over many generations in the laboratory) to the ideally suited model system Tribolium castaneum to explore how these evolutionary forces interact and impact on the key processes underlying biodiversity. Understanding how these fundamental forces, singly and in conjunction, influence species divergence remains a major challenge in evolutionary biology. Participation of sexual selection in driving speciation is supported by substantial theoretical evidence. Theory further suggests that evolutionary conflicts (such as between the sexes or between host and parasite) might also accelerate extinction. Additional complexity is introduced by including the environmental context, linking back to natural selection. Direct experimental tests of the above concepts are essentially lacking. I will explicitly target this gap by exploiting powerful experimental evolution, incorporating the interplay between sexual selection intensity, host-parasite conflict, and adaptation to increasing temperature. Projects will assess how selection under evolutionary conflict and environmental change affects both adaptation and extinction rates, aiming to elucidate underlying mechanisms. Additionally, building on clear phenotypic divergence in key traits across experimental evolution lines, I will significantly expand on previous work by assessing patterns of divergence in gene expression, concentrating on target genes associated with reproduction, immunity and heat shock. This research will be of particular interest to scientists working in the fields of evolutionary biology and behavioural ecology, but also to ecologists, reproductive biologists, and conservation biologists. As Tribolium beetles are widespread agricultural pests, results will also be relevant to more applied researchers.

PHOTOchemical Formation of Nitrous Acid in the Atmosphere (PHOTONA)

Nitrous Acid (HONO) has attracted significant attention during the last few years since recent field measurements have demonstrated that the photolysis of HONO can be the dominant source of OH radicals in the lower atmosphere. The OH radical is responsible for the degradation of most air pollutants and for the formation of harmful photooxidants. Thus, the identification and quantification of the sources of HONO are of major importance. To explain un-expected high daytime concentrations of HONO, different photochemical sources have been proposed. However, the exact origin and the magnitude of HONO fluxes over irradiated rural and urban surfaces are still open questions, which have to be solved to understand and quantify the oxidation capacity of the atmosphere. In the proposed project, these questions are aimed to be answered by the integration of selected laboratory, field and modelling studies. In the laboratory studies, different photochemical sources of HONO will be investigated in photoreactors by the help of very sensitive and selective instrumentation to enable the simulation of atmospheric relevant conditions. In the field studies, the daytime source strength of HONO will be quantified over irradiated surfaces by the help of a mixed gradient / eddy-covariance technique at a field site near Paris (INRA/Grignon), which is already used for flux measurements of NOx and O3 since two years. The HONO fluxes will be parameterized for different types of surfaces (e.g. pure soil and crop) as a function of measured variables (solar intensity, NO2, nitrate, etc.). In addition, daytime gradients measurements in the altitude range 10-200 m will be performed under urban conditions at the meteorological tower at Forschungszentrum Karlsruhe to better quantification the impact of the HONO photolysis on the radical budget for an extended altitude range. The results from the lab and field studies - including data from recent other studies - will be used to improve existing box, 1-D and 3-D models with the focus on the better description and quantification of the oxidation capacity of the boundary layer. The outcome of the project will have an essential impact on the understanding of the photochemistry of the lower atmosphere.

Evolution of plant morphological diversity in plant-insect mutualisms

Most plants rely on insects for their pollination, protection (e.g., from herbivores) and/or seed dispersal, and have formed a mutually beneficial interaction, or mutualism. The current research investigates the evolution of plant traits involved in plant-insect mutualisms. In particular, it focuses on the evolution of extrafloral nectaries (EFNs): secretory structures on plant parts outside the flower, which offer carbohydrate-rich, water-based secretions (=nectar) to ants in return for their protection from herbivores (i.e. protective mutualisms). EFNs occur in some ferns and over hundred families of flowering plants, especially the legume family. However, their phylogenetic distribution within families, morphological diversity and evolution, and evolutionary role are poorly understood. Also EFN plant-ant interactions are known to shape entire tropical and savannah-like ecosystems, but their unexpected occurrence in deserts - where plants need to manage water carefully - has been studied only in a few cacti. This study investigated the diversity and evolution of EFNs at three different levels: (1) in the Leguminosae, the third largest and second economically most important angiosperm family, which also dominates many kinds of vegetation worldwide; (2) in the legume genus Senna, a case study where EFNs represent a key innovation (see past SNF project by B. Marazzi); and (3) in Sonoran Desert plants. Current results show that EFNs occur in species of over 130 legume genera (over twice as many as in the last published account of EFNs in this family). They are particularly abundant in the subfamily Mimosoideae, and may have evolved independently at least 30 times in the family. This incredible number of origins suggests the action of some evolutionary (perhaps genetic) precursor that allowed some clades to evolve EFNs more 'easily' given ceartin selective regimes. Most legume EFNs occur on the (typically pinnate) leaves, less often on stipules and different parts of inflorescences. In Senna, ancestral leaf EFNs appear to have evolved first between the proximal pair of leaflets only (some 40 Million years ago), and later also between the other pairs of leaflets (several times) or only at the base of the leaf stalk (once). In the Sonoran Desert area (including also mountain habitats), EFNs may occur in species from up to 32 families, in several cacti and in particular Leguminosae, dominant in this vegetation. EFNs have apparently been reduced but have been retained in a functional state (i.e., secreting nectar) in most desert legumes, and are thus capable of participating in protective mutualisms with desert ants. This research shows that EFNs are more widespread in plants than previously thought, suggesting that we may have underestimated the role of protective ant-plant interactions in shaping ecosystem ecology and evolution

Depletion of algal toxin-contaminated water using selective biofilters based on plant-produced antibodies (plantibodies)

Although the use of genetically modified plants for bioremediation, or the in situ cleaning of contaminated sites, has been known for quite some time, little attention has so far been paid to the production of antibodies in plants and their ex vivo application in selective depletion. Therefore, highly affine and specific antibodies against algal toxins using microcystin as an example will be produced in plants at low cost within this research project. The basis is a monoclonal antibody (Mab 10E7, species: mouse) generated in a former research project. The sequence of the variable domains will be determined, optimized for plants and sub cloned into suitable plant transformation vectors, which already contain constant antibody sequences. In addition, a scFv fragment containing different tag sequences and fusion proteins will be constructed. Leaf-based (tobacco) as well as seed-based (barley) systems will be used.Affinity-purified plant-produced antibodies (plantibodies) will be characterized in detail for their binding properties using microtitre plate-ELISA and surface plasmon resonance (SPR). The monoclonal mouse antibody will be used as reference. To assure cost-efficiency for future applications, roughly purified fractions (sequential pH and temperature treatment followed by filtration) will be tested for the upscaling. Following immobilization of the plantibody fractions on suitable substrates, for instance membranes, porous polymer monoliths or in porous glasses, their application for depletion will be defined using model water samples spiked fortified with microcystins.

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