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    The MiLA tool: Modeling greenhouse gas emissions and cumulative energy demand of energy crop cultivation in rotation
    (Amsterdam : Elsevier, 2016) Peter, Christiane; Specka, Xenia; Aurbacher, Joachim; Peter Kornatz, Peter Kornatz; Herrmann, Christiane; Heiermann, Monika; Müller, Janine; Nendel, Claas
    Crop rotations are part of current agricultural practice, since they and their effects can contribute to a sustainable agricultural cropping system. However, in current Life Cycle Assessment (LCA) studies, crop rotation effects are insufficiently considered, since these effects are difficult to measure. LCA studies from crop production typically take only one vegetation period into account. As a result, the consideration of how the assessed crop is influenced by the previous crop (crop rotation effects) including: (1) nutrient carryover, (2) reduction in operational requirements and (3) different intensity and timing of farming activities, is outside of the system boundary. However, ignoring these effects may lead to incorrect interpretation of LCA results and consequently to poor agricultural management as well as poor policy decisions. A new LCA tool called the “Model for integrative Life Cycle Assessment in Agriculture (MiLA)” is presented in this work. MiLA has been developed to assess GHG emissions and cumulative energy demands (CED) of cropping systems by taking the characteristics of crop cultivation in rotation into account. This tool enables the user to analyze cropping systems at farm level in order to identify GHG mitigation options and energy-efficient cropping systems. The tool was applied to a case study, including two crop rotations in two different regions in Germany with the goal of demonstrating the effectiveness of this tool on LCA results. Results show that including crop rotation effects can influence the GHG emission result of the individual crop by − 34% up to + 99% and the CED by − 16 up to + 89%. Expanding the system boundary by taking the whole crop rotation into account as well as providing the results based on different functional units improves LCA of energy crop production and helps those making the assessment to draw a more realistic picture of the interactions between crops while increasing the reliability of the LCA results.
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    Risk efficiency of irrigation to cereals in northeast Germany with respect to nitrogen fertilizer
    (Amsterdam : Elsevier, 2016) Meyer-Aurich, Andreas; Gandorfer, Markus; Trost, Benjamin; Ellmer, Frank; Baumecker, Michael
    The potential role of irrigation of cereals as a response to climate change is under debate. Especially under temperate continental conditions empirical evidence of crop yield response to irrigation in interaction with nitrogen fertilizer supply is rare. Besides mean yield effects, irrigation reduces yield variance, which may be an incentive for farmers to use irrigation. This paper investigates the risk-efficiency of irrigation in cereal production in a temperate continental climate, based on data from a long term field experiment on a sandy soil. Irrigation and no irrigation of winter rye (Secale cereale) and winter barley (Hordeum vulgare) were investigated in three different nitrogen (N) fertilizer levels. Crop yield response data (1995–2010) to irrigation and N fertilizer were used to calculate net returns, certainty equivalents (CE) for different levels of risk aversion and the conditional value at risk (CVaR) as a downside risk indicator in two price scenarios. The scenarios were calculated with a total cost and a partial budget approach. Irrigation was found to be profit-maximizing in all partial budget calculations, which sometimes required higher N input to be profit-maximizing. Irrigation and N fertilizer reduction were identified as risk mitigation strategies, even though their impact was limited. Irrigation reduced the downside risk only in the partial budget calculations. The analysis based on the CE did not show improved risk efficiency with irrigated management options. In contrast, reduced fertilizer input proved to be risk efficient at specific levels of risk aversion. The price expectations of winter rye and winter barley had a much higher impact on the ranking of the management options than risk aversion based on the crop yield variances. At low crop prices for all levels of risk aversion, irrigation of winter barley and winter rye was only economically justified if fixed costs for irrigation were not taken into account. At high crop prices, irrigation of winter barley was also justified based on the total cost calculation. However, this advantage was only given at a very low level of risk aversion. With increasing levels of risk aversion irrigation was not efficient based on the CE in the total cost accounting scenario. In conclusion, irrigation of cereals can contribute to downside risk mitigation and increased profits, if fixed costs for irrigation are covered. However, this conclusion holds only when irrigation is combined with an increased N intensity. If total costs need to be accounted for, irrigation in cereals is not an appropriate risk reduction strategy and a reduction of N input is more effective.
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    A brief dataset on the model-based evaluation of the growth performance of Bacillus coagulans and l-lactic acid production in a lignin-supplemented medium
    (Amsterdam : Elsevier, 2017) Glaser, Robert; Venus, Joachim
    The data presented in this article are related to the research article entitled “Model-based characterization of growth performance and l-lactic acid production with high optical purity by thermophilic Bacillus coagulans in a lignin-supplemented mixed substrate medium (R. Glaser and J. Venus, 2016) [1]”. This data survey provides the information on characterization of three Bacillus coagulans strains. Information on cofermentation of lignocellulose-related sugars in lignin-containing media is given. Basic characterization data are supported by optical-density high-throughput screening and parameter adjustment to logistic growth models. Lab scale fermentation procedures are examined by model adjustment of a Monod kinetics-based growth model. Lignin consumption is analyzed using the data on decolorization of a lignin-supplemented minimal medium.
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    Impact of energy crop rotation design on multiple aspects of resource efficiency
    (Hoboken, NJ : Wiley, 2016) Peter, Christiane; Glemnitz, Michael; Winter, Katharina; Kornatz, Peter; Müller, Janine; Heiermann, Monika; Aurbacher, Joachim
    Biogas production can cause environmental problems due to a biased alignment of one energy crop used as a feedstock, e.g., maize in Germany. Diversification of crop rotations and resource-efficient management can be the key to sustainable crop management. Four crop rotations on eight sites across Germany were evaluated in terms of their resource efficiency (area use, energy, and economic efficiency) to derive options. Analysis revealed high variation in all indicators under review, with a high variance explanation by the interaction between crop rotation and regional characteristics. Furthermore, results indicate that high area-specific methane yields do not equate to high energy efficiency. Crop management adaptation is a useful tool for optimizing resource efficiency.
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    Kontrollierte Entleerung mit ganzflächigen Austrageinrichtungen
    (Darmstadt : KTBL, 2016) Franke, Georg; Weigler, Fabian; Mellmann, Jochen; Müller, Peter
    Bei der Entleerung komplexer Schüttgutapparate und Silos kann die Austrageinrichtung am Behälterboden einen erheblichen Einfluss auf den Energiebedarf des Prozesses und die Produktqualität nehmen. In der Praxis hat sich eine Vielzahl von Austrageinrichtungen entwickelt, die sich nach Art ihres Verschließmechanismus und der Gestaltung ihrer feststehenden Einbauten unterscheiden. Experimentelle Untersuchungen am Schüttgut Weizen haben gezeigt, dass einige ganzflächige Austrageinrichtungen zu ausgeprägten Fließprofilen führen. Aufgrund ihres konstruktiven Aufbaus bieten derartige Systeme ein bislang ungenutztes Potenzial, die Schüttgutbewegung örtlich zu beeinflussen und eine kontrollierte Entleerung umzusetzen. Auf der Grundlage eines Prototyps wird am Leibniz-Institut für Agrartechnik und Bioökonomie e.V. (ATB) eine neuartige Austrageinrichtung entwickelt. Erste Untersuchungen haben gezeigt, dass feststehende Leitorgane an den Wänden zu einer verlangsamten Entleerung am Rand der Austrageinrichtung führen. Der gänzliche Verzicht auf diese Einbauten führt hingegen zu einer starken Beschleunigung in den wandnahen Regionen. Durch eine optimierte Gestaltung feststehender Einbauten soll es zukünftig möglich sein, die Schüttgutbewegung örtlich über den Verschließmechanismus zu steuern. Darüber hinaus soll mit der neuartigen Austrageinrichtung untersucht werden, inwieweit sich auch der Trocknungsverlauf in Getreide- Durchlauftrocknern beeinflussen und vergleichmäßigen lässt.
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    Untersuchung der Trocknungsluftströmung an einer neu entwickelten Geometrie für Dächerschachttrockner
    (Darmstadt : KTBL, 2016) Scaar, Holger; Weigler, Fabian; Franke, Georg; Mellmann, Jochen
    Der Dächerschachttrockner wurde in den letzten Jahren hinsichtlich der Trocknungseffizienz, Regelungstechnik und Leistungssteigerung vielfach analysiert. Dennoch besteht erheblicher Optimierungsbedarf bezüglich Energieeffizienz und Gleichmäßigkeit der Trocknung. Zur Analyse des spezifischen Energieverbrauchs und der Homogenität des Trocknungsprozesses wurden thermodynamische Prozesszustände anhand der konventionellen Trocknergeometrie numerisch und experimentell analysiert. Aus den gewonnenen Ergebnissen wurde eine neue Trocknergeometrie entwickelt, mit der eine deutliche Effizienzsteigerung erreicht werden soll. Wie die strömungsmechanische Analyse des ersten Designentwurfs ergab, ist weiterer Entwicklungsbedarf bis zur Praxisüberführung erforderlich. Während im Kernflussbereich in der Trocknermitte gleichmäßige Strömungsbedingungen nachgewiesen werden konnten, ist die Konstruktion in den wandnahen Bereichen zu optimieren.
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    CE-UV/VIS and CE-MS for monitoring organic impurities during the downstream processing of fermentative-produced lactic acid from second-generation renewable feedstocks
    (London : BioMed Central, 2016) Laube, Hendrik; Matysik, Frank-Michael; Schmidberger, Andreas; Mehlmann, Kerstin; Toursel, Andreas
    During the downstream process of bio-based bulk chemicals, organic impurities, mostly residues from the fermentation process, must be separated to obtain a pure and ready-to-market chemical. In this study, capillary electrophoresis was investigated for the non-targeting downstream process monitoring of organic impurities and simultaneous quantitative detection of lactic acid during the purification process of fermentatively produced lactic acid. The downstream process incorporated 11 separation units, ranging from filtration, adsorption and ion exchange to electrodialysis and distillation, and 15 different second-generation renewable feedstocks were processed into lactic acid. The identification of organic impurities was established through spiking and the utilization of an advanced capillary electrophoresis mass spectrometry system
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    Direct production of lactic acid based on simultaneous saccharification and fermentation of mixed restaurant food waste
    (Amsterdam : Elsevier, 2016) Pleissner, Daniel; Demichelis, Francesca; Mariano, Silvia; Fiore, Silvia; Gutiérrez, Ivette Michelle Navarro; Schneider, Roland; Venus, Joachim
    This study introduces to a one-step process for the fermentative production of L(+)-lactic acid from mixed restaurant food waste. Food waste was used as carbon and nitrogen source in simultaneous saccharification and fermentation (SSF) using Lactobacillus sp. or Streptococcus sp. strains for L(+)-lactic acid production. Waste consisted of (w/w) 33.5% starch, 14.8% proteins, 12.9% fat and 8.5% free sugars. Lactobacillus sp. strains showed a productivity of 0.27–0.53 g L−1 h−1 and a yield of 0.07–0.14 g g−1 of theoretically available sugars, while Streptococcus sp. more efficiently degraded the food waste material and produced lactic acid at a maximum rate of 2.16 g L−1 h−1 and a yield of 0.81 g g−1. For SSF, no enzymes were added or other hydrolytic treatments were carried out. Outcomes revealed a linear relationship between lactic acid concentration and solid-to-liquid ratio when Streptococcus sp. was applied. Statistically, from a 20% (w/w) dry food waste blend 52.4 g L−1 lactic acid can be produced. Experimentally, 58 g L−1 was achieved in presence of 20% (w/w), which was the highest solid-to-liquid ratio that could be treated using the equipment applied. Irrespective if SSF was performed at laboratory or technical scale, or under non-sterile conditions, Streptococcus sp. efficiently liquefied food waste and converted the released nutrients directly into lactic acid without considerable production of other organic acids, such as acetic acid. Downstream processing including micro- and nanofiltration, electrodialysis, chromatography and distillation gave a pure 702 g L−1 L(+)-lactic acid formulation.
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    Biochars in soils: towards the required level of scientific understanding
    (Vilnius : VGTU Press, 2016) Tammeorg, Priit; Bastos, Ana Catarina; Jeffery, Simon; Rees, Frédéric; Kern, Jürgen; Graber, Ellen R.; Ventura, Maurizio; Kibblewhite, Mark; Amaro, António; Budai, Alice; Cordovil, Cláudia M.d.S.; Domene, Xavier; Gardi, Ciro; Gascó, Gabriel; Horák, Ján; Kammann, Claudia; Kondrlova, Elena; Laird, David; Loureiro, Susana; Martins, Martinho A.S.; Panzacchi, Pietro; Prasad, Munoo; Prodana, Marija; Puga, Aline Peregrina; Ruysschaert, Greet; Sas-Paszt, Lidia; Silva, Flávio C.; Teixeira, Wenceslau Geraldes; Tonon, Giustino; Delle Vedove, Gemini; Zavalloni, Costanza; Glaser, Bruno; Verheijen, Frank G.A.
    Key priorities in biochar research for future guidance of sustainable policy development have been identified by expert assessment within the COST Action TD1107. The current level of scientific understanding (LOSU) regarding the consequences of biochar application to soil were explored. Five broad thematic areas of biochar research were addressed: soil biodiversity and ecotoxicology, soil organic matter and greenhouse gas (GHG) emissions, soil physical properties, nutrient cycles and crop production, and soil remediation. The highest future research priorities regarding biochar’s effects in soils were: functional redundancy within soil microbial communities, bioavailability of biochar’s contaminants to soil biota, soil organic matter stability, GHG emissions, soil formation, soil hydrology, nutrient cycling due to microbial priming as well as altered rhizosphere ecology, and soil pH buffering capacity. Methodological and other constraints to achieve the required LOSU are discussed and options for efficient progress of biochar research and sustainable application to soil are presented.
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    Methanbildungspotenziale verschiedener Pflanzenarten aus Energiefruchtfolgen
    (Darmstadt : KTBL, 2016) Herrmann, Christiane; Plogsties, Vincent; Willms, Matthias; Hengelhaupt, Frank; Eberl, Veronika; Eckner, Jens; Strauß, Christoph; Idler, Christine; Heiermann, Monika
    Das Methanbildungspotenzial ist ein entscheidendes Qualitätsmerkmal von Biomassen bei ihrer Nutzung als Einsatzstoff für die Biogasproduktion. Von 769 unter einheitlichen Bedingungen silierten Erntegütern aus Energiefruchtfolgen wurden mittels Batch-Gärtests in zwei verschiedenen Versuchsanlagen spezifische Methanausbeuten ermittelt. Daraus konnten Richtwerte für mittlere Methanausbeuten je Fruchtart und Fruchtfolgestellung, Schnitt bzw. Trockenmassebereich oder Entwicklungsstadium zur Ernte für 93 verschiedene pflanzliche Biomassen abgeleitet werden. Die Ergebnisse stellen eine umfassende Datengrundlage dar, die in Verbindung mit Biomasseerträgen für die Abschätzung von Methanhektarerträgen zur ökonomischen und ökologischen Bewertung von Energiefruchtfolgen, zur Planung und Auslegung von Biogasanlagen sowie zur Entscheidung hinsichtlich des Anbaus alternativer pflanzlicher Kosubstrate und der Konzeption nachhaltiger Biogasfruchtfolgen genutzt werden können.