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Field and laboratory studies of aerosol formation from halogenated precursor gases

Das Projekt "Field and laboratory studies of aerosol formation from halogenated precursor gases" wird vom Umweltbundesamt gefördert und von Technische Universität Berlin, Institut für Technischen Umweltschutz durchgeführt. This project was part of the HaloProc research unit on natural halogenation processes, and explored the impact of reactive halogen species on aerosol formation in field and laboratory experiments. Field studies were focused on the Lake King salt lake area in Western Australia. New particle formation events were frequently observed and characterized by measuring the temporal evolution of the submicron aerosol size distributions, and collecting aerosol samples for subsequent chemical analysis. 9 out of 11 measurement days in 2013 showed secondary aerosol formation with particle growth rates from 2.9 to 25.4 nm h^-1. Raman spectroscopy and ultrahigh resolution mass spectrometry revealed a contribution of organohalogen compounds (mostly organochlorine) to the secondary organic aerosol, however, organosulfate and organonitrate formation seemed to play a larger role in the studied environment. Nevertheless, a new experimental approach that made use of a mobile Teflon chamber set up above the salt crust and the organic-rich mud layer of various salt lakes directly linked new particle formation to the hypersaline environment of Western Australia. For more detailed process studies, these field results provided realistic scenarios and constraints for simulation experiments in the laboratory. Salt lake conditions were successfully simulated in aerosol chamber experiments and showed secondary aerosol formation in the presence of light and organic precursor compounds. The particle formation dynamics and the chemical speciation of aerosol samples, which were collected from the chamber experiments and analyzed by Raman spectroscopy and mass spectrometry, indicated a coupling of aqueous phase chemistry and secondary aerosol formation. In particular, the Fe(II) concentrations of the simulated salt lakes were a key control for the intensity of new particle formation. In saline environments with low pH values and high solar radiation, Fe(II) might be converted to Fe(III) in the presence of organic matter in a Fenton-like reaction, which can act as a major source for highly reactive OH radicals in the aqueous phase. On the one hand, this expands the potential oxidation pathways for organic compounds, which led to a larger chemical diversity. On the other hand, Fe(II)-controlled aqueous phase chemistry competes with secondary aerosol formation in the gas phase, which led to reduced particle formation in our experiments. While it is premature to fully incorporate these findings in chemistry box models, additional laboratory studies provided experimental data that will guide the development of model parameterizations, e.g., for the organic aerosol yield from the oxidation of organic compounds by chlorine and bromine, or for reactive bromine loss due to uptake in secondary organic aerosol. In conclusion, this project bridged gaps between field studies of halogen-influenced new particle formation in the real world and laboratory experiments within the HaloProc research u

Charakterisierung der mit Natriumpyrophosphat löslichen organischen Bodensusbstanz mittels FT-IR

Das Projekt "Charakterisierung der mit Natriumpyrophosphat löslichen organischen Bodensusbstanz mittels FT-IR" wird vom Umweltbundesamt gefördert und von Leibniz-Zentrum für Agrarlandschaftsforschung (ZALF) e.V., Institut für Bodenlandschaftsforschung durchgeführt. Zusammensetzung und Menge der organischen Bodensubstanz (OBS) werden durch die Landnutzungsform beeinflußt. Die OBS läßt sich nach ihrer Abbaubarkeit und nach ihrer Löslichkeit in verschiedene Pools einteilen. So kann die wasserlösliche organische Bodensubstanz (DOM) als Maßzahl für die abbaubare OBS herangezogen werden. Mit Natriumpyrophosphat-Lösung als Extraktionsmittel läßt sich ein weit größerer Anteil der OBS erfassen, da der stabilisierende Bindungsfaktor zwischen OBS und Bodenmineralen entfernt wird. Extrahiert man zuerst mit Wasser und anschließend mit Natriumpyrophosphat-Lösung, erhält man im letzten Schritt den schwer abbaubaren OBS-Anteil. Über die funktionelle Zusammensetzung der organischen Substanz dieser Pools und deren Abhängigkeit von Landnutzungsformen ist relativ wenig bekannt. Ziel der geplanten Untersuchung ist es, den Pool der löslichen abbaubaren und schwer abbaubaren OBS zu quantifizieren und deren funktionelle Zusammensetzung mittels FT-IR Spektroskopie zu erfassen. Die so gewonnenen Daten sollen der Validierung von Soil Organic Matter Turnover modellen (z.B. Roth 23.6) dienen und die im Modell berechneten Pools um einen qualitativen Term ergänzen. In Zusammenarbeit mit anderen Arbeitsgruppen sollen im DFG-Schwerpunktprogramm 1090: ;Böden als Quelle und Senke für CO2 die Pools der löslichen abbaubaren und schwer schwer löslichen, schwer abbaubaren organischen Bodensubstanz (OBS) quantifiziert, die funktionelle Zusammensetzung dieser Pools mittels FT-IR Spektroskopie erfasst und Abbaubarkeit der erhaltenen Extrakte überprüft werden, um Mechanismen, die zur Stabilisierung der OBS führen, aufzuklären.

SFB Waldoekosystemsanierung

Das Projekt "SFB Waldoekosystemsanierung" wird vom Umweltbundesamt gefördert und von Universität für Bodenkultur Wien, Institut für Botanik durchgeführt. Projektteil 2 des Spezialforschungsbereiches'Waldoekosystemsanierung'. Interpretation of water stress indicators from soil parameters.

Clean Sky Technology Eco Design (Clean Sky ECO)

Das Projekt "Clean Sky Technology Eco Design (Clean Sky ECO)" wird vom Umweltbundesamt gefördert und von Airbus Helicopters Deutschland GmbH durchgeführt. The Eco-Design ITD (ED-ITD) gathers and structures from one side activities concerned specifically with development of new material and process technologies and demonstration on airframe and rotorcraft related parts stressing the ecolonomic aspects of such new technologies; from the other side, activities related to the All Electrical Aircraft concept related to small aircraft. ED-ITD is directly focused on the last ACARE goal: 'To make substantial progress in reducing the environmental impact of the manufacture, maintenance and disposal of aircraft and related products'. Reduction of environmental impacts during out of operation phases of the aircraft lifecycle can be estimated to around 20 % reduction of the total amount of the CO2 emitted by all the processes (direct emissions and indirect emissions i.e. produced when producing the energy) and 15 % of the total amount of the energy used by all the processes. In addition, expected benefit brought by the All Electric Aircraft concept to be highlighted through the conceptual aircraft defined in the vehicle ITDs is estimated to around 2% fuel consumption reduction due to mass benefits and better energy management. The status of the global fleet in the year 2000 constitutes the baseline against which achievements will be assessed. Progress toward these goals will result not only from ED internal activities but also from the collaboration with the relevant cross-cutting activities in GRA , GRC, SFWA (business jet platform) and SGO (electrical systems).

Element cycles in mountain regions under various land use

Das Projekt "Element cycles in mountain regions under various land use" wird vom Umweltbundesamt gefördert und von Universität Bayreuth, Fachgruppe Geowissenschaften, Bayreuther Zentrum für Ökologie und Umweltforschung (BayCEER), Lehrstuhl für Agrarökosystemforschung durchgeführt. Research question: What is the role of agricultural land use in changes of nutrient cycles and losses dependingon surface slope and climate? Approach: Annual balance of main nutrients for 3-4 main agricultural farms based on fertilizer input, partitioning of nutrients in above and below ground plant parts, output with harvest, losses with DOM and erosion (in collaboration with other TP). The balances will be done depending on agricultural practices in Eger and Haean Catchment and will be compared with adjacent grassland and forest. Obtained element cycles will be upscaled from farm area to the level of both catchments basins depending on specific land use, surface slope and climate. Research question: Can we reconstruct previous erosion and nutrient losses and separate them under forest and under agricultural use? Approach: Undisturbed sediment cores (7 for Eger and 7 for Haean) will be taken from the lakes and soils of landscapes subordinated to agricultural fields. Three radiocarbon data of wood particles at increasing depth for each sediment core will be used as references. The age of the bottom sediment layer should be less than 1000 years. The total content of C, N, P, K, Mg, Ca, Si will be analyzed in individual laminae or sediment layers. Conclusions will be drawn based on the thickness of the laminae, their elements content and the ratio between nutrients and Si. The conclusions will be proven by 13C (vegetation change) and 15N (N input by fertilizers) of individual laminae. Research question: What are the best management practices for sloping uplands? Approach: Measured element cycles and losses under various agriculture practice will be analysed and practices with the least nutrient losses and erosion will be selected. The best management practices for landscapes with different slopes will be elaborated.

B 2: Lateral water flow and transport of agrochemicals - Phase 1

Das Projekt "B 2: Lateral water flow and transport of agrochemicals - Phase 1" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Bodenkunde und Standortslehre durchgeführt. The project aims at developing a model of the dynamics of agrochemicals (fertilisers, pesticides) and selected heavy metals on a regional scale as a function of cropping intensity in the highland areas of Northern Thailand. The model shall predict the effects of cropping intensity on mobility and leaching of agrochemicals in the agriculturally used system itself but also on the chemical status of neighbouring ecosystems including downstream areas. The methods for measuring and estimating the fluxes of agrochemicals in soils will be adapted to the conditions of the soils and sites in Northern Thailand. Fluxes of agrochemicals will be measured in fruit tree orchards on the experimental sites established together with projects B1, C1 and D1. Also, processes governing the dynamics of agrochemicals will be studied. The objectives for the first phase are as follows: - To identify suitable study sites - To establish the methods for measuring the fluxes of agrochemicals in the study sites - To adopt the analytical procedures for pesticides - To identify and parametrise the processes governing the mobility of agrochemicals - To identify the major chemical transformation processes for agrochemicals in the soils of the project area - To establish models of the fate of agrochemicals an the plot scale. Dynamics of agrochemicals include processes of mobilisation/immobilisation, degradation and transport. Both, experiments and field inventories are needed to elucidate the complex interaction of the various processes. Field measurements of the fluxes of nutrient elements (N, P, K, Ca, Mg, Mn, Zn, Cu), pesticides and some heavy metals will be conducted at different regional scales (plot, agricultural system, small catchment, region). Laboratory and field experiments consider chemical, physicochemical and biological processes. Biological processes and degradation of pesticides will not be considered in the first phase of the project, however, they should be included later on. The project as a whole is broken down into three essential parts, which consecutively follow each other. The subproject is methods- and processes-orientated. Methods, which were developed in Hohenheim to quantify the fluxes of chemicals in soils have to be adapted to meet the requirements of the specific conditions in the study area. Recently, these methods are already under development in tropical environments (Vietnam, Costa Rica). After adaptation the methods will be used to yield flux data on the plot scale. These data are needed to help deciding which of the hypothesised processes are of major importance for modelling the dynamics of agrochemicals. The final outcome of this project phase are models of the fate of agrochemicals as a function of management intensity on the plot scale.

D 6.1: Improving fruit set and quality standards of mango in the mountainous area of Vietnam

Das Projekt "D 6.1: Improving fruit set and quality standards of mango in the mountainous area of Vietnam" wird vom Umweltbundesamt gefördert und von Universität Hohenheim, Institut für Kulturpflanzenwissenschaften, Fachgebiet Ertragsphysiologie der Sonderkulturen (340f) durchgeführt. A major problem in mango production in Northern Vietnam is a premature fruit drop. However, the underlying plant processes in response to environmental and/or crop management factors are not understood. There is a general belief that this phenomenon is caused by different combinations of stressing factors which may vary between different regions and sites. In the mountainous area of northern Vietnam (Son La Province), fruit drop in mango may be caused by relatively hot, dry prevailing winds which typically occur in February/March. Consequently, it has to be determined which plant process responds sensitively to specific environmental conditions and subsequently causes, through its alteration, premature fruit drop. The identification of the physiological basis of premature fruit drop not only is of scientific interest but also of commercial significance, allowing the development of effective, fruit drop reducing crop management strategies and thus ensuring a economically sustainable cultivation of mango in this region. The research project has two main parts; environmental crop physiology and fruit quality. The environmental crop physiology part investigates whether premature fruit drop is caused by high temperature/vapour pressure deficit (VPD) conditions and related to: 1. temperature dependence of pollen tube growth and flower quality; 2. altered carbon fixation and carbon partitioning between sources (leaves) and sinks (fruit), thus possible limitations of carbon supply to developing mango fruit; 3. altered basipetal auxin export from fruit and fruit ethylene concentration. The fruit quality part will primarily carry out sensory fruit analyses and establish harvest quality criteria with the aim to improve the economic returns and thereby the economic situation of the fruit growers in the long-term.

Impacts of Solar Home System Usage in Rural Burkina Faso

Das Projekt "Impacts of Solar Home System Usage in Rural Burkina Faso" wird vom Umweltbundesamt gefördert und von Rheinisch-Westfälisches Institut für Wirtschaftsforschung e.V. RWI, Kompetenzbereich Umwelt und Ressourcen durchgeführt. In remote areas with low electrification rates, Solar Home Systems (SHS) can be seen as a promising alternative to the investment-intensive extension of the electricity grid. The Dutch Ministry of Foreign Affairs provides funding to a project in Burkina Faso that offers SHS to rural households using a market-based approach. The SHS that are distributed can provide electric lighting and - depending on the chosen capacity of the system - allow for the usage of small electric appliances up to colored television. As part of the series of impact evaluations of development activities supported by the Netherlands on behalf of the Dutch Ministry of Foreign Affairs, RWI and ISS assess the socio-economic impact of the usage of SHS such as improved living conditions, time savings, increased security, better health conditions, and educational attainment trough extended study hours. The idea is to conduct a difference-in-difference approach based on household surveys before and after the intervention, in combination with propensity score matching (PSM) to better match control and treatment households on pre-program characteristics (e.g. education, socio-economic status, income, asset-ownership, characteristics of the villages they live in). Following the roll-out plan of Yeelen Ba's activities, a baseline survey was conducted in November 2010 based on a random sample of villages that are in the program's catchment area. In total, 1,200 households in 40 villages (30 households per village) were interviewed. A particular focus was on the use of appliances and energy expenditures, as well as convenience and comfort aspects before and after the SHS was installed. For the difference-in-difference approach the sample will be divided into a treatment group consisting of households who will have obtained an SHS in the meantime and a control group consisting of untreated households. The follow-up survey will be conducted two years after the baseline survey in November 2012. All households will be revisited and differences in the changes in the outcome variables between the treatment group and the control group will be assessed, providing insights about how ownership of an SHS changes the socio-economic living conditions of the households.

Biomass Fuell Cell Utility System (BIOCELLUS)

Das Projekt "Biomass Fuell Cell Utility System (BIOCELLUS)" wird vom Umweltbundesamt gefördert und von Technische Universität München, TUM School of Engineering and Design, Fakultät für Maschinenwesen, Lehrstuhl für Energiesysteme durchgeführt. Objective: Energy from Biomass needs highly efficient small-scale energy systems in order to achieve cost effective solutions for decentralized generation especially in Mediterranean and Southern areas, and for applications without adequate heat consumer. Thus fuel cells are an attractive option for decentralized generation from biomass and agricultural residues but they have to meet at least two outstanding challenges: 1. Fuel cell materials and the gas cleaning technologies have to treat high dust loads of the fuel gas and pollutants like tars, alkalines and heavy metals. 2. The system integration has to allow efficiencies of at least 40-50 percent even within a power range of few tens or hundreds of kW. This proposal addresses in particular these two aims. Hence the first part of the project will focus on the investigation of the impact of these pollutants on degradation and performance characteristics of SOFC fuel cells in order to specify the requirements for appropriate gas cleaning system (WP 1-2). These tests will be performed at six existing gasification sites, which represent the most common and applicable gasification technologies. WP 3 will finally test and demonstrate the selected gas cleaning technologies in order to verify the specifications obtained from the gasification tests. The results will be used for the development, installation and testing of an innovative SOFC - Gasification concept, which will especially match the particular requirements of fuel cell systems for the conversion of biomass feedstock. The innovative concept comprises to heat an allothermal gasifier with the exhaust heat of the fuel cell by means of liquid metal heat pipes. Internal cooling of the stack and the recirculation of waste heat increases the system efficiency significantly. This so-called TopCycle concept promises electrical efficiencies of above 50 percent even for small-scale systems without any combined processes.

Pasture rehabilitation on, and management of degraded areas in the Andes of South Ecuador

Das Projekt "Pasture rehabilitation on, and management of degraded areas in the Andes of South Ecuador" wird vom Umweltbundesamt gefördert und von Universität Bayreuth, Fachgruppe Biologie, Bayreuther Zentrum für Ökologie und Umweltforschung (BayCEER), Lehrstuhl für Pflanzenphysiologie durchgeführt. Project abstract: This knowledge transfer project will be centered in the San Francisco valley in the South Ecuadorian Andes. However, the problem of abandoning pastures because of heavy infestation by weeds, in particular by bracken fern (Pteridium spec.), is a general issue in the tropical Andes. Pastures which have been abandoned for that reason amount meanwhile to 11Prozent of the area of the San Francisco valley. Infestation by bracken fern and shrubs is a consequence of the traditional use of fire for clearing of the natural forest and pasture management. Growth of both, bracken and woody weeds, is fostered by recurrent burning. In a 2-phase experiment on a heavily bracken-infested slope at c. 2000 m altitude, substantial control of the weed and subsequent pasture rehabilitation could be achieved. In the planned project, this procedure shall be scaled-up to farm level and the altitudinal range of repasturisation shall be extended from 1000 m to 2400 m altitude. To that end local farmers will put respective parts of their land to the projects disposal and public authorities will provide man-power. There are several challenges to be met: (i) Long-term bracken infestation has depleted the soils from nutrients, in particular P and N. Therefore targeted fertilization is needed for profitable grass productivity. (ii) Since bracken can never be completely eradicated, its regrowth must be suppressed by trampling, i.e. frequent grazing. A sustainable grazing management has to be developed which corresponds to soil fertility. (iii) The dominating pasture grass is the C4-type grass Setaria sphacelata. It is growing well in a warm climate but its competitive strength in the harsher climate above 2000 m is low. Bracken as a C3-type plant is less dependent on the temperature. To this adds that it occurs in 2 species in the area, one of which is an upland type. Thus the climate gradient over the elevational transect will influence the competitive strength of both competitors. Therefore the suitability of the traditional monoculture of this grass species for pasture rehabilitation shall be tested in the context of a comprehensive pasture management experiment which the farmers will be involved. (iv) A special problem is the high oxalate concentration in the growing parts of the Setaria leaves which can cause calcaemia in cattle. In a pot experiment which will be run in collaboration with a research team of the UTPL, feeding quality and toxicity of a monotonous diet of Setaria will be tested. Beside the experimental areas, demonstration sites will be installed where regular training workshops will be organized to encourage the farmers to apply the developed rehabilitation and management strategy to their own farms.

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