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Kreins P.,Thunen Institute of Rural Studies | Henseler M.,Thunen Institute of Rural Studies | Henseler M.,University of Le Havre | Anter J.,Thunen Institute of Agricultural Technology | And 2 more authors.
Water Resources Management | Year: 2015

Climate change is expected to impact agricultural production conditions and groundwater resources. The climate change impacts are expected to be of particular importance for the German region North Rhine-Westphalia. Due to a high population density and intensive partial irrigation of agricultural production, future resource conflicts for groundwater are expected. An integrated model framework consisting of climate, crop-soils and ground-water models represents the regional heterogeneous climatic, geographic and agronomic conditions. The integrated model framework simulates the irrigation demand and groundwater recharge. An ex-post comparison between the simulated reference period (1961 to 1990) and statistical data prove a good model validity. The climate change scenario for the future period 2051 to 2080 assumes decreasing precipitation and increasing transpiration. The simulated total irrigation demand increases by nearly 20 times compared to the reference period (1961 to 1990) and increases regionally to more than 40 mm/ha. Decreasing groundwater recharge results in a tenfold increased share of irrigation water from groundwater. This share accounts regionally for more than 30%. The results indicate important impacts for both agricultural production and other groundwater users. © Springer Science+Business Media Dordrecht 2015. Source

Hahne J.,Thunen Institute of Agricultural Technology
Landtechnik | Year: 2013

Relevant trace gas emissions from two chicken houses in small group housing were measured from 2009 to 2012. The emissions were varying widely and, in case of ammonia, depending on the dung removal rates. Between those the ammonia emission increased daily up to 120 %. The trace gas and particulate matter emissions as well could be correlated with the volume flow at a constant stable management. While methane, nitrous oxide and hydrogen sulfphide emissions were low with 9 ± 7, 7 ± 2 and 4 ± 1 g per head and year at specific air flow rates of 8.2 ± 1.4 m3 per head and hour, ammonia emission for this housing system was in a common range with 148 ± 29 g per head and year. The carbon dioxide emission exceeded with 46 kg per head and year the ammonia emission by a factor of 311. Specific odor emissions varied with 15-84 odor units (OU) per second (s) and livestock unit (LU). In mean the odor emission was 43 OU s-1 LU-1. Source

Willke T.,Thunen Institute of Agricultural Technology
Applied Microbiology and Biotechnology | Year: 2014

This paper presents an updated critical review about several attempts to contribute methionine (Met) to the world market with an emphasis on fermentation processes, especially from natural biological sources. Analytical methods for the determination of methionine are reviewed as well as applications in feed, food, pharmacy, and medicine. Fermentation studies published within the last five decades are elucidated critically, mainly with respect to the sulfur balance, substrate yield, and the analytical validity. From all the published fermentation data, it can be concluded that up to now no more than 5 g/L methionine are achievable without using genetically modified organisms (GMOs). The highest l-methionine concentration from natural sources reached so far amounts to 35 g/L and is published as a patent using a GMO of Escherichia coli. The review closes with a comprehensive overview of the role and activities of global methionine manufacturers. Some current market data is also presented. © 2014, Springer-Verlag Berlin Heidelberg. Source

Clauss M.,Thunen Institute of Agricultural Technology | Hoppe A.,University of Veterinary Medicine Hannover | Hartung J.,University of Veterinary Medicine Hannover
Gefahrstoffe Reinhaltung der Luft | Year: 2013

Measurements were conducted at the trade fair Biotechnica 2011 in Hannover, Germany, The concentrations of different particle size fractions In the air of the exhibition hall were measured by Bio-aerosol-Spectrometer and the numbers of airborne bacteria and mould spores were determined by cultivation and by a fluorescence microscopic method. Bacteria-containing particles were also classified with the latter method. The concentrations of bacteria (on average 30,500 cells/m3 and 410 cfu/m3) and moulds (on average 1,090 cells/m3 and 31 cfu/m3) were slightly higher than in ambient air. Their concentrations showed large variations during the trade show as well as those of different particle size fractions. Both were influenced heavily by the subjectively observed numbers of visitors and the general activity in the course of the day. Of the bacteria detected with the fluorescence microscopic method, 45% were most likely of human origin and found on skin scales and in small droplets. Of the cultivated bacteria 70% belonged to the Gram positive cocci. The fluorescence microscopic method is suitable for the rapid detection and classification of selected airborne particles in the field. Source

Westphal G.A.,Ruhr University Bochum | Krahl J.,Coburg University of Applied Sciences | Munack A.,Thunen Institute of Agricultural Technology | Rosenkranz N.,Ruhr University Bochum | And 5 more authors.
Environmental Science and Technology | Year: 2013

Research on renewable fuels has to assess possible adverse health and ecological risks as well as conflicts with global food supply. This investigation compares the two newly developed biogenic diesel fuels hydrotreated vegetable oil (HVO) and jatropha methyl ester (JME) with fossil diesel fuel (DF) and rapeseed methyl ester (RME) for their emissions and bacterial mutagenic effects. Samples of exhaust constituents were compared after combustion in a Euro III heavy duty diesel engine. Regulated emissions were analyzed as well as particle size and number distributions, carbonyls, polycyclic aromatic hydrocarbons (PAHs), and bacterial mutagenicity of the exhausts. Combustion of RME and JME resulted in lower particulate matter (PM) compared to DF and HVO. Particle numbers were about 1 order of magnitude lower for RME and JME. However, nitrogen oxides (NOX) of RME and JME exceeded the Euro III limit value of 5.0 g/kWh, while HVO combustion produced the smallest amount of NOX. RME produced the lowest emissions of hydrocarbons (HC) and carbon monoxide (CO) followed by JME. Formaldehyde, acetaldehyde, acrolein, and several other carbonyls were found in the emissions of all investigated fuels. PAH emissions and mutagenicity of the exhausts were generally low, with HVO revealing the smallest number of mutations and lowest PAH emissions. Each fuel showed certain advantages or disadvantages. As proven before, both biodiesel fuels produced increased NOX emissions compared to DF. HVO showed significant toxicological advantages over all other fuels. Since jatropha oil is nonedible and grows in arid regions, JME may help to avoid conflicts with the food supply worldwide. Hydrogenated jatropha oil should now be investigated if it combines the benefits of both new fuels. © 2013 American Chemical Society. Source

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