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Found 54 results.

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.

Analysis of dairy production systems differentiated by location

Das Projekt "Analysis of dairy production systems differentiated by location" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Bonn, Institut für Lebensmittel- und Ressourcenökonomik (ILR), Professur Wirtschafts- und Agrarpolitik.Dairy farming across Germany displays diverse production systems. Factor endowment, management, technology adoption as well as competitive dynamics in the local or regional land, agribusiness and dairy processing sectors contribute to this differentiation on farm level. These differences impact on the ability of dairy farms and regional dairy production systems to successfully respond to pressures arising from future market and policy changes. The overall objective of the research activities of which this project is a part of, is to develop a thorough understanding of the processes that govern the spatial dynamics of dairy farm development in different regions in Germany. The central hypothesis of this research project is that management system and technological choices differ systematically across local production and market conditions. The empirical approach will focus on the estimation of farm specific nonparametric cost functions for dairy farms located in across Germany differentiated by time and location. A spatially differentiated data base with information on input use, resource availability, as well as local market conditions for land and output markets will be compiled. The nonparametric approach is specifically suited to disclose a more accurate representation of dairy production system heterogeneity across locations and time compared to parametric concepts as it provides the necessary flexibility to accommodate non-linearities relevant for a wide domain of explanatory variables. The methodology employed goes beyond the state of the art of the literature as it combines kernel density estimation with a Bayesian sampling approach to provide theory consistent parameters for each farm in the data sample.The specific methodological hypothesis is that the nonparametric approach is superior to current parametric techniques and this hypothesis is tested using statistical model evaluation. Regarding the farm management and technological choices, we hypothesize that land suitability for feed production determines the farm intensity of dairy production and thus management and technological choices. With respect to the ability of farms to successfully respond to market pressures we hypothesize that farms at the upper and lower tail of the intensity distribution both can generate positive returns from dairy production. These last two hypotheses will be tested using the estimated spatially differentiated farm specific costs and marginal costs.The expected outcomes are of relevance for the agricultural sector and the food supply chain economy as a whole as fundamental market structure changes in the dairy sector are ongoing due to the abolition of the quota regulation in the years 2014/2015. Thus, exact knowledge about differences and development of dairy cost heterogeneity of farms within and between regions are an important factor for the actors involved in the market as well as the political support of this process.

Schwerpunktprogramm (SPP) 1315: Biogeochemische Grenzflächen in Böden; Biogeochemical Interfaces in Soil, The detritusphere as the biogeochemical interface for bacterial and fungal degradation of MCPA

Das Projekt "Schwerpunktprogramm (SPP) 1315: Biogeochemische Grenzflächen in Böden; Biogeochemical Interfaces in Soil, The detritusphere as the biogeochemical interface for bacterial and fungal degradation of MCPA" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Hohenheim, Institut für Bodenkunde und Standortslehre.The detritusphere is an excellent model to study microbial-physicochemical interactions during degradation of the herbicide MCPA. Whereas during the first phase of SPP 1315 we focused on bacterial and fungal abundance at the soil litter interface and carbon flow between different compartments, the second phase will be devoted to elucidating complex regulation mechanisms of MCPA degradation in the detritusphere: (1) At the cellular level, co-substrate availability and laccase abundance might be important regulators, (2) at the community level, bacteria harbouring different classes of tfdA genes might control degradation of MCPA and (3) at the microhabitat level, interaction between MCPA degraders and organo-mineral surfaces as well as transport processes might be important regulators. The concept of hierarchical regulation of MCPA degradation will be included into the modelling of small-scale microbial growth, MCPA transport and MCPA degradation near the soil-litter interface.

Calcium cycling in the soil-fig-bat compartment of a neotropical rain forest on spatially heterogeneous substrate

Das Projekt "Calcium cycling in the soil-fig-bat compartment of a neotropical rain forest on spatially heterogeneous substrate" wird/wurde gefördert durch: Deutsche Forschungsgemeinschaft. Es wird/wurde ausgeführt durch: Universität Bern, Geographisches Institut, Gruppe Bodenkunde.Calcium supply in tropical soils is variable and frequently low. In spite of the heterogeneous Ca supply, some plant species, such as figs, maintain high Ca concentrations in their tissues. Figs are keystone species with more than proportional importance for the functioning of a tropical rain forest. High Ca concentrations in fig fruits may render them particularly attractive for frugivorous vertebrates. We propose to study the whole Ca cycling from soil through a selected fig species, Ficus insipida Willd. and frugivorous bats, their main dispersers, back to soil. The study will be conducted in Panama on sites differing in soil Ca status to assess the importance of soil Ca availability for fig fruit content and bat reproduction. We will quantify aboveground Ca fluxes for 16 trees along a gradient of Ca availability in soil. We will determine (1) Ca concentrations in soils, figs and leaves, (2) nutritional quality of fig and other bat-dispersed fruits and their importance for Ca balance in relation to reproduction of fruit-eating bats, (3) Ca fluxes with litterfall, throughfall, stemflow, bat pellets and faeces, (4) the importance of the contribution of bats to the Ca cycle of individual fig trees, and (5) the effect of fig trees on soil Ca concentrations.

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.

Light in - Light out

Das Projekt "Light in - Light out" wird/wurde gefördert durch: Kommission der Europäischen Gemeinschaften Brüssel. Es wird/wurde ausgeführt durch: Universität Basel, Institut für Anorganische Chemie.Mankind is approaching a crisis in energy generation and utilization. Traditional fossil fuel reserves are diminishing and legislative issues regarding CO2 emission will make use of existing lower grade reserves unattractive. New technologies have to be developed to satisfy the ever-increasing energy demand and to maximize efficient energy usage. The materials chemist, through the design of new materials with novel properties and by controlling interfacial interactions between materials, will play a crucial role in these endeavours and in enabling the paradigm shift that is required. This project is centred around two core and inter-related issues (i) energy generation from photovoltaics using sunlight and (ii) efficient lighting devices based on light-emitting electrochemical cells (LECs) and organic light emitting diodes (OLEDs). Both of these topics are areas of intense activity world-wide. Within Europe the PIs research group is one of the leaders in the field. However, as research efforts in these areas are proving successful and proof-ofprinciple systems are being established and optimized, a new factor needs to be addressed. State of the art photovoltaic devices based upon the dye-sensitized solar cell (DSC) most frequently utilize inorganic dyes comprising ruthenium complexes of oligopyridine ligands. The projected next generation mass market OLEDs and prototype LECs are based upon iridium complexes containing cyclometallated pyridine ligands. A traditional criticism of these approaches related to the costs of the raw materials although this is in reality low compared to the costs of other components. However, the price reflects in part the availability of these metals and in this respect devices based upon ruthenium (1 ppb by atom in Earth crust) or iridium (0.05 ppb by atom in Earth crust) are unsustainable. This project is concerned with the development of complexes based upon abundant and sustainable first row transition metals to replace second and third row transition metals in these devices. Initial efforts will centre upon complexes of copper(I) and zinc(II) which have well-established photochemistry and photophysics making them suitable for such applications. The PI has already established proof-of-principle for the replacement of ruthenium by copper in DSCs and is a world leader in this technology. The work on the two projects will involve (i) materials synthesis and characterization (ii) computational modelling (iii) device construction and testing and (iv) property optimization.

The sustainable freight railway: Designing the freight vehicle track system for higher delivered tonnage with improved availability at reduced cost (SUSTRAIL)

Das Projekt "The sustainable freight railway: Designing the freight vehicle track system for higher delivered tonnage with improved availability at reduced cost (SUSTRAIL)" wird/wurde gefördert durch: Kommission der Europäischen Gemeinschaften Brüssel. Es wird/wurde ausgeführt durch: Consorzio Per La Ricerca e lo Sviluppo di Tecnologie Per il Trasporto Innovativo.A sustainable and efficient freight transport in Europe plays a vital role in having a successful and competitive economy. Freight transport is expected to grow by some 50 % (in tonne-kilometres) by 2020. However rail has, in many areas, been displaced from a dominant position as road transport services have grown and developed in capability and levels of sophistication that have not been matched by rail service providers. SUSTRAIL aims to contribute to the rail freight system to allow it to regain position and market and the proposed solution is based on a combined improvement in both freight vehicle and track components in a holistic approach aimed at achieving a higher reliability and increased performance of the rail freight system as a whole and profitability for all the stakeholders. The SUSTRAIL integrated approach is based on innovations in rolling stock and freight vehicles (with a targeted increased in speed and axle-load) combined with innovations in the track components (for higher reliability and reduced maintenance), whose benefits to freight and passenger users (since mixed routes are considered) are quantified through the development of an appropriate business case with estimation of cost savings on a life cycle basis. In fact, a holistic approach to vehicle and track sustainability has to be taken, since improvements in track design and materials alone are not enough as demands on the rail system increase. Contributions from the different topic areas (vehicles, track, operations) will be demonstrated on real routes, offering geographic dispersion as well as differences in type, speed, and frequency of traffic. A strong multidisciplinary consortium committed to concrete actions aligned toward a common outcome has been grouped for the achievement of the challenging objectives of the project with a balanced combination of Infrastructure managers, freight operators and Industry, including Large and Small enterprises, with support from Academia.

Effects of biochar amendment on plant growth, microbial communities and biochar decomposition in agricultural soils

Das Projekt "Effects of biochar amendment on plant growth, microbial communities and biochar decomposition in agricultural soils" wird/wurde gefördert durch: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung. Es wird/wurde ausgeführt durch: Forschungsinstitut für biologischen Landbau Deutschland e.V..Biochar has a great potential to ameliorate arable soils, especially those that are low in organic matter due to intensive use or erosion. Biochar is carbonised organic material with high porosity that brings about changes in physical, chemical and biological soil functions. Biochar amended soils show a higher water and cation exchange capacity with reduced leaching and enhanced availability of plant nutrients. The microbial biomass in biochar amended soils is enhanced and more diverse. Biochar is stabilised organic material, which is likely to remain for hundreds of years in the soil. Photosynthetically fixed atmospheric CO2 stabilised in biochar may thus act as a direct carbon sink and help to mitigate climate change. As feedstock and production conditions produce different biochar qualities predictions of effects in soil need to consider biochar and soil properties case by case. To date biochar has been approved to ameliorate highly weathered tropical soils with positive effects on crop growth and yield. Distinct microbial groups were reported to be enhanced in soils but if this depends on the particular soil or biochar or a combination of both is an open question, especially in temperate climates. Likewise, it is not known if microorganisms colonising biochar surfaces are responsible for its mineralization or if they just use the new niches provided. The aim of the proposed project is to investigate the influence of two biochar types on soil-plant systems by determining i) soil nutrient availability, plant growth and nutrient uptake, ii) structure and function of soil microbial communities, iv) the decomposition and fate of biochar in soils. We will use two loessial soils from the well-known DOK-trial with different soil organic matter content. Other soils from the region will be selected to provide a wider range of soil quality, in particular pH. The biochars will be produced by pyrolysis and hydrothermal carbonization (HTC) from the C4-plant Miscanthus gigantea. Pyrolysis derived material has bigger pore sizes due to the evaporating gasses and is commonly alkaline, whereas the HTC derived biochar has a finer pore size, a much higher oxygen content and more acidic functional groups.

Use of scavengers in the pretreatment of lignocellulosic biomass for improved chemicals production

Das Projekt "Use of scavengers in the pretreatment of lignocellulosic biomass for improved chemicals production" wird/wurde gefördert durch: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung. Es wird/wurde ausgeführt durch: Eidgenössische Technische Hochschule Zürich, Institut für Verfahrenstechnik.Combined production of fuels and chemicals from wood This project examines an innovative approach for pre-treating wood in order to produce fuels and chemicals. In this approach, the researchers combine hot water treatment with so-called radical scavengers. Background Biofuels from wood have economic and ecological advantages as compared to fuels from corn starch and sugar cane (costs, availability, no conflict with food production). However, it is much more difficult to transform wood into biofuels. This is because the components of wood-cellulose, hemicelluloses and lignin-are strongly interwoven to protect the plant against external forces, in particular. In the production of biofuels, this impedes the enzymatic degradation of cellulose and lignocellulose into their respective sugars, which can subsequently be fermented to produce, for example, bio-ethanol. Therefore, it is necessary to pre-treat the wood in order to break up its structure and improve the enzymatic access. Aim One possible treatment of biomass would be to dissolve it in hot water, but this is hampered by cross-linking reactions of emerging lignin fragments. So-called 'radical scavengers' can stop these undesired reactions and make the wood much more soluble. This procedure is aimed at achieving, on the one hand, a cellulose fraction with improved enzymatic access and, on the other hand, a high-quality lignin fraction. The latter serves as a starting material for the production of aromatic chemicals. Significance The examined approach is aimed at producing fuels and aromatic chemicals which are today still gained from petrochemical resources. This opens up new avenues for gradually replacing fossil oil with biomass.

Arid Southern Levant: a joint environmental and human history for the Holocene, derived from new archives of climate change (Dead Sea edge, Jordan)

Das Projekt "Arid Southern Levant: a joint environmental and human history for the Holocene, derived from new archives of climate change (Dead Sea edge, Jordan)" wird/wurde gefördert durch: Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung. Es wird/wurde ausgeführt durch: Universität Bern, Departement Biologie, Institut für Pflanzenwissenschaften.This project proposes to explore the potential of sedimentary sequences from arid Southern Levant to record past environmental and climate changes that can be compared with the evolution of human societies during the Holocene. The Levant, crucible of history, actually possesses very few archives of past climate change in its most arid parts, which restricts the possibility to compare, on a regional scale, environmental variation and the evolution of human communities through time. The region is characterised by contrasted bioclimatic conditions, from Mediterranean-type to arid. Most of the known records of environmental change are located in the moister, Mediterranean zones of the region, where increased water availability permits the presence - or the better preservation - of high-resolution and continuous archives of past climates. However, the potential of the arid environments of the Southern Levant (roughly corresponding to modern Israel, Palestine, and Jordan) to harbour records of Holocene (last ca. 11,500 years) climate change, is far from being exploited to its full extend. Following the unique discovery of Holocene organic, peat-like deposits in the rain-shadow of the Dead Sea area in Jordan, this project proposes to investigate the potential of this currently arid region to record past environmental and climate change. The organic sequences present in the mountain slopes East of the Dead Sea have been shown to contain very good pollen information. Results from a preliminary pollen study provided in particular evidence for the periodic extension of Mediterranean-type forest vegetation, from the upper Mediterranean plateaus down to the study area. These organic sequences can be further exploited to generate more precisely dated (mainly through radiocarbon techniques) and higher-resolution records of climate and environmental change for the Holocene. Pollen data will be complemented by a series of other proxies: charcoal studies indicating recurrent fires, spores and fungi revealing past grazing activities, diatom assemblages showing changes in the water quality, increased detrital content marking periods of enhanced erosion. All these results can then be integrated into dynamic models of local environmental changes and vegetation response. Furthermore, the same area contains multiple sequences of spring carbonates (tufa / travertine) waiting to be studied. The stable isotopic (oxygen and carbon) composition of spring carbonates can provide a good record of past climate change, as it registers variations in environmental factors such as temperature, parent-water composition (itself related to the source and amount of rainfall), and evaporation. The presence of carbonate sequences near organic sequences on the edge of the Dead Sea, offers an unprecedented occasion to directly compare the isotopic variations of carbonate series with environmental variations recorded in the peaty archives.

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