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- ItemHydrothermal carbonization (HTC): Near infrared spectroscopy and partial least-squares regression for determination of selective components in HTC solid and liquid products derived from maize silage(Amsterdam : Elsevier, 2014) Reza, M. Toufiq; Becker, Wolfgang; Sachsenheimer, Kerstin; Mumme, JanNear-infrared (NIR) spectroscopy was evaluated as a rapid method of predicting fiber components (hemicellulose, cellulose, lignin, and ash) and selective compounds of hydrochar and corresponding process liquor produced by hydrothermal carbonization (HTC) of maize silage. Several HTC reaction times and temperatures were applied and NIR spectra of both HTC solids and liquids were obtained and correlated with concentration determined from van-Soest fiber analysis, IC, and UHPLC. Partial least-squares regression was applied to calculate models for the prediction of selective substances. The model developed with the spectra had the best performance in 3–7 factors with a correlation coefficient, which varied between 0.9275–0.9880 and 0.9364–0.9957 for compounds in solid and liquid, respectively. Calculated root mean square errors of prediction (RMSEP) were 0.42–5.06 mg/kg. The preliminary results indicate that NIR, a widely applied technique, might be applied to determine chemical compounds in HTC solid and liquid.
- ItemThe 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, ClaasCrop 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.
- ItemRisk 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, MichaelThe 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.
- ItemA 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, JoachimThe 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.
- ItemEffects of storage conditions and duration on physicochemical and microbial quality of the flour of two cassava cultivars (TME 419 and UMUCASS 36)(Milton Park : Taylor & Francis, 2015) Uchechukwu-Agua, Amarachi D.; Caleb, Oluwafemi J.; Manley, Marena; Opara, Umezuruike LinusThis study investigated the effects of storage conditions: cool (15 ± 1°C, 90% relative humidity (RH)), ambient (23 ± 2°C, 60% RH) and higher (38 ± 2°C, 60% RH) on changes in physicochemical quality attributes of two cassava flour cultivars (TME 419 and UMUCASS 36) packaged in paper bags and stored for 12 weeks. Physicochemical and microbial qualities were studied at weeks 0, 4, 8 and 12. Moisture content decreased from 12.0% to 7.1% and 9.8% to 6.8% in cultivars ‘TME 419’ and ‘UMUCASS 36’, respectively. Carotenoid content was higher in cultivar (cv.) ‘UMUCASS 36’ (2.5 ± 0.10 mg/g) compare to cv. ‘TME 419’ (1.8 ± 0.11 mg/g). Colour indices of the cassava flour were significantly influenced by storage duration. A slight decrease in microbial load from 5.4 to 4.8 log CFU/g was observed, with increase in temperature from 15°C to 38°C at the end of storage. The ambient storage condition best maintained nutritional and physicochemical quality.
- ItemEnzyme-based lignocellulose hydrolyzation – Brief data survey for cellulase performance characterization on behalf of the Sauter mean diameter of raw material particles(Amsterdam : Elsevier, 2015) Glaser, RobertThe data presented here supports the informational background of enzyme-based lignocellulose hydrolyzation, cellulase characterization, and sugar yield prediction for the work “Enzyme-based lignocellulose hydrolyzation – Sauter mean diameter of raw materials as a basis for cellulase performance characterization and yield prediction” by Glaser [1]. Glucose yields from the enzymatic hydrolysis of the raw materials were shown as a function of cellulase enzyme loading as well as of particle size with different solid loading. The data for the proposed methods of the determination of enzyme activity in inhomogeneous samples of lignocellulosic raw materials are presented. The data of the empirical model that was developed for the prediction of hydrolysis yields for different enzyme concentrations, substrate specific particle size, and solid loadings, are given. Data are also given in relation of terms of scale-up opportunities.
- ItemImpact 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, JoachimBiogas 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.
- ItemDynamic variation of the microbial community structure during the long-time mono-fermentation of maize and sugar beet silage(Milton Park : Taylor & Francis, 2015) Klang, Johanna; Theuerl, Susanne; Szewzyk, Ulrich; Huth, Markus; Tölle, Rainer; Klocke, MichaelThis study investigated the development of the microbial community during a long-term (337 days) anaerobic digestion of maize and sugar beet silage, two feedstocks that significantly differ in their chemical composition. For the characterization of the microbial dynamics, the community profiling method terminal restriction fragment length polymorphism (TRFLP) in combination with a cloning-sequencing approach was applied. Our results revealed a specific adaptation of the microbial community to the supplied feedstocks. Based on the high amount of complex compounds, the anaerobic conversion rate of maize silage was slightly lower compared with the sugar beet silage. It was demonstrated that members from the phylum Bacteroidetes are mainly involved in the degradation of low molecular weight substances such as sugar, ethanol and acetate, the main compounds of the sugar beet silage. It was further shown that species of the genus Methanosaeta are highly sensitive against sudden stress situations such as a strong decrease in the ammonium nitrogen (NH4 +-N) concentration or a drop of the pH value. In both cases, a functional compensation by members of the genera Methanoculleus and/or Methanosarcina was detected. However, the overall biomass conversion of both feedstocks proceeded efficiently as a steady state between acid production and consumption was recorded, which further resulted in an equal biogas yield.
- ItemExperimente zum Partikelfluss an einer neu entwickelten Geometrie für Dächerschachttrockner(Darmstadt : KTBL, 2014) Weigler, Fabian; Franke, Georg; Scaar, Holger; Mellmann, JochenUm große Mengen an Körnerfrüchten über einen längeren Zeitraum lagerfähig zu machen, werden weltweit zunehmend Dächerschachttrockner (DST) eingesetzt. Trocknereinbauten, die ungünstig konstruiert oder angeordnet sind, können eine breite Verweilzeitverteilung des zu trocknenden Gutes verursachen. Dadurch kommt es lokal zu unterschiedlichen Trocknungsbedingungen, die zu einer inhomogenen Trocknung und damit zu einem erhöhten spezifischen Energieverbrauch, zu wirtschaftlichen Verlusten und zu Qualitätseinbußen führen. Mit dem Ziel der Sicherung der Produktqualität und der Steigerung der Energieeffizienz wurde daher eine neuartige Apparategeometrie entwickelt. Um das traditionelle Design mit der neu entwickelten Geometrie hinsichtlich der Partikeldurchströmung vergleichen zu können, wurden Durchflussversuche am Modellgut Weizen mit eingefärbten Körnern als Tracerpartikel im Technikumsmaßstab durchgeführt.
- ItemZielflächenorientierte, präzise Echtzeit-Fungizidapplikation in Getreide(Darmstadt : KTBL, 2015) Dammer, Karl-Heinz; Hamdorf, André; Ustyuzhanin, Anton; Schirrmann, Michael; Leithold, Peer; Leithold, Hermann; Volk, Thomas; Tackenberg, MariaIm Rahmen eines Verbundprojektes wurden Echtzeit-Applikationstechnologien mit berührungslosen Sensoren für präzise Fungizid-Spritzungen in Getreide entwickelt. Das Entscheidungshilfe- System proPlant expert.classic bzw. die Internetversion proPlant expert.com (proPlant GmbH) empfiehlt geeignete Fungizide und Dosierungen für ein bestimmtes Infektionsszenario der acht wichtigsten Blatt- und Ährenkrankheiten von Winterweizen. Das Precision- Farming-Modul „Fungizid“, welches auf dem Terminal in der Traktorenkabine läuft, steuert das präzise Spritzverfahren. Das Modul bestimmt die lokale Zielapplikationsmenge während des Spritzens durch Nutzung des lokalen Ultraschallsensorwerts als Eingabeparameter. In den Jahren 2013 und 2014 wurden Feldversuche in Winterweizen durchgeführt, um die Beziehung zwischen den Sensorwerten (Ultraschall- und Kamerasensor) und den Pflanzenparametern Pflanzenoberfläche (Leaf Area Index, LAI) sowie Biomasse zu analysieren. Diese sind für einen örtlich angepassten variablen Fungizideinsatz zur Bemessung der Spritzmenge wichtig. Die Messungen wurden mehrmals während der Vegetationsperiode an visuell ausgewählten Stichprobenpunkten entsprechend der unterschiedlichen Bestandsdichte durchgeführt. Nach Änderungen an der Sensortechnik konnten für 2014 signifikante lineare Regressionsmodelle zur Beschreibung der Beziehung zwischen den Sensorwerten und den zwei Pflanzenparametern LAI sowie Biomasse gefunden werden.