Agricultural Energy Crops Research Articles

The role of the «Sugar Beet» magazine in popularization of agricultural energy crops and technologies of their processing for biofuel (1997–2018)

Introduction. Ukraine in the Russian Empire and in Soviet times, as you know, occupied a leading position in the production of beets and sugar. But until 1997, Ukrainian beet growers did not have their own professional Ukrainian-language print publication, although there was an urgent need for it. The industry journal Sugar Beet, which, in fact, became the first communication platform in Ukraine for the implementation of production-scientific and educational-explanatory functions related to the development of beet-growing and bioenergy, was founded in 1997. Sugar Beet was one of the first journals in independent Ukraine in 1998 to be included in the List of Professional Scientific Publications of Ukraine Recommended for the Publication of the Main Results of Doctoral and Candidate's Dissertations in the Department of Agricultural Sciences. The key place in the columns of the publication was occupied not only by sugar beets (Beta vulgaris), but also by the coverage of research work related to the launch of the process of moving some dual-application crops in the research fields and research laboratories of the institute located on Batyi Hill, and some new and until recently little-known for Ukraine so-called ‘energy’ crops (sugar sorghum, miscanthus, switchgrass, Sudan grass, salix, etc.), in special bioenergy plantations to obtain biomass and process it into various types of energy, which later stimulated and, in fact, symbolized a breakthrough in terms of forming a new independent bioenergy (phytoenergy) industry in Ukraine. 1076 original research and production articles were published in the columns, the authors of which are not only scientists and practitioners of the crop industry, but creators of high-yielding varieties in Ukraine and abroad – in Russia, Kazakhstan, Germany, Switzerland, Belarus and others. countries; At the same time, each 5–6 articles published under the headings such as Non-traitional Crops, Biotechnology, Breeding and Genetics, Agrotechnology or Bioenergy directly or indirectly covers the problems of development of so-called special ‘energy’ plants. A section on world and domestic trends in the development of renewable and non-traditional energy sources has found a permanent residence on the pages of the journal.
 Conclusion. The study shows that one of the oldest scientific and production editions – Sugar Beet – has played an important and timeless role not only in the development of the beet and sugar industry, but also in the history of bioenergy. Its issues are still available online on the official website of the IBCSB (see journal.sugarbeet.gov.ua.).

ENERGY CROPS AS ALTERNATIVE AGRICULTURE CROPS FOR BIOMASS PRODUCTION IN MACEDONIA AND BULGARIA

In this review the focus is on few agricultural energy crops, which means crops that are grown exclusively or primarily for the purpose of producing biomass for energy purposes in an agricultural rather than a forestry context. However, cultivation of most of these crops is restricted to certain regions, e.g. by requirements for a certain climate zones. Having in mind the similar agro ecological conditions in R. Macedonia and Bulgaria, but also needs of the crops for successful growth and development, species as miscanthus, switch grass and sweet sorghum are introduced as a potentially used energetic plant species for this part of the Balkan region.

Biomass valorisation of Arundo donax L., Miscanthus × giganteus and Sida hermaphrodita for biofuel production

Abstract In the context of the growing demand for biomass, which is being encouraged by the EU directives on the promotion of the use of renewable energy, recent investigations have been increasingly focused on fast-growing energy crops. The aim of this study was to investigate the energy properties of three types of agricultural energy crops: Arundo donax L., Miscanthus × giganteus and Sida hermaphrodita. This investigation looked into the content of non-combustible and combustible matter, higher and lower heating values, lignocellulose content, and biomass macro-elements. The results indicate that the energy values of these crops are comparable, while their lignocellulose content shows significant variations. Thus, Arundo donax L. can best be utilised as solid biofuel due to its highest lignin content, while Miscanthus × giganteus and Sida hermaphrodita L. can be used for both liquid and solid biofuels production. As far as Arundo donax L. is concerned, a higher ash level should be taken into consideration.

Process parameters and changes in the microbial community patterns during the first 240days of an agricultural energy crop digester.

Commercial biogas production takes place by complex microbial communities enclosed in controlled “technical ecosystems”. Once established, the communities tend to be resilient towards disturbances, although the relative abundance of their members may vary. The start-up phase, during which the community establishes itself, is therefore decisive for the later performance of the reactor. In this study, we followed the first 240 days of a standard agricultural energy crop digester consisting of a 400 m3 plug flow fermenter and a 1000 m3 agitated post digester, operated at 40–45 °C. The feed consisted of corn and later grass silage augmented by ground wheat. Changes in both the eubacterial and methanogenic archaeal communities were followed by automated ribosomal intergenic spacer analysis (ARISA). In addition the copy number of the methyl-coenzyme reductase A (mcrA)-genes found in all known methanogens were followed by quantitative PCR, while selected samples from two phases—one early, one late—of the community structure development were subjected to high throughput sequencing. Biogas volume and composition (CH4, CO2, H2, H2S, O2), pH, ammonia-N, and volatile fatty acids (VFA), were measured as part of the routine process control. VFA/TIC values were calculated on this basis. Whereas the total gas production of the plant established itself at about 2500 m3 biogas per day within the first months, the composition of the microbial communities showed distinct spatial and temporal differences over the investigated time period. Absolute values for DNA isolation procedures are difficult to certify, hence comparative results on community structures obtained using standardized ARISA with identical primers are of value. Moreover, ARISA patterns can be statistically analyzed to identify distinct subgroups and transitions between them as well as serial correlations. Thereby the microbial community and its structural development can be correlated with statistical relevance to changes in operational (feed) and process parameters (pH-value, biogas composition). In particular when augmented by deep sequencing data of judiciously chosen samples, this allows a hitherto unknown level of insight into the performance of technical biogas plants.Electronic supplementary materialThe online version of this article (doi:10.1186/s13568-016-0219-7) contains supplementary material, which is available to authorized users.

Critical comparison of different model structures for the applied simulation of the anaerobic digestion of agricultural energy crops

Different model structures were compared to simulate the characteristic process variables of the anaerobic digestion of maize, sugar beet and grain silage. Depending on the type and number of the required components, it can be shown that in comparison to the complex Anaerobic Digestion Model No. 1 (ADM1) different simplified model structures can describe the gas production rate, ammonia nitrogen and acetate concentration or pH value equally well. Since the reduction of the predominantly fast kinetics of the methanogenesis, acetogenesis or acidogenesis will only have little effect on the simulation of the specific gas production, it can be proven that the hydrolysis is the rate-limiting step during the uninhibited anaerobic digestion of complex particulate substrates. However, the stoichiometric comparison reveals that the model protein gelatine is not suitable for a representative characterization of agricultural energy crops.

Emission of N2O from Biogas Crop Production Systems in Northern Germany

There is a growing concern that greenhouse gas (GHG) emissions during agricultural energy crop production might negate GHG emission savings which was not intended when promoting the use of renewable energy. Nitrous oxide (N2O) is a major GHG, and in addition, it is the most powerful ozone-depleting compound that is emitted by human activity. The use of N fertilizers and animal manures is the main anthropogenic source of N2O emissions. In spite of their high relevance, we still have limited understanding of the complex underlying microbial processes that consume or produce N2O and their interactions with soil types, fertilizers (rate and types), plants, and other environmental variables. In a 2-year field experiment, we compared two important biogas crops in two different agro-ecological regions of northern Germany for their productivity and GHG emissions, using the closed-chamber technique and high time-resolution sampling. Silage maize, which is currently the most widespread crop grown for biogas fermentation purposes in Germany, was compared with an alternative bioenergy crop at each site. The three forms of nitrogen fertilizers/manures were given: calcium ammonium nitrate, cattle/pig slurry, and biogas residue. The greatest N2O flux activity occurred in the period of May–July in all crops and at both sites. Flux patterns indicated pronounced effects of soil moisture-soil mineral-N interactions which were also seen as causation of the higher N2O fluxes in the bioenergy crop maize compared to the other tested energy crops. However, the N2O emission per unit methane production (specific N2O emission) was clearly lower in soils planted with maize due to significantly higher methane hectare yield of maize. Our data suggest a linear relationship between increasing N input and increases in N2O emission in both years at site with sandy loam texture where highest N2O fluxes were measured. At sandy loam site, the percentage of applied N being emitted as N2O was 1.9 and 1.1 % in soils cropped with maize and 0.9 and 0.8 % in soils cropped with wheat during the investigation period 2007–2008 and 2008–2009, respectively. In contrast, at site with sandy soil texture, the percentage of applied N emitted as N2O was only 0.6 and 0.7 % in maize soils and 0.4 and 0.3 % in grassland during 2007–2008 and 2008–2009 period, respectively. Higher daily and annual N2O emissions at the sandy loam site were attributed to the finer soil texture and higher denitrification activity. The present study provides a very good basis for the assessment of direct emissions of greenhouse gases from relevant biogas crops in North-West Europe.

Interest in energy wood and energy crop production among Finnish non-industrial private forest owners

EU targets and regulations regarding energy production and the reduction of greenhouse gas emissions have been tightening in the 2000s. In Finland the targets are planned to be achieved mainly by increasing the use of biomass. Wood already accounts for a marked proportion of Finnish energy production, but additional reserves are still available. Energy crop production also has considerable potential. Practically all Finnish farmers are also forest owners. Therefore, private forest owners are in a decisive position regarding the supply of energy wood and crops in Finland. In this paper the future supply of biomass is examined according to their past behaviour, intentions and attitudes. Finnish forest owners have a positive attitude towards the use of wood and crops in energy production. Price is becoming more critical as a motive for the supply of energy wood. Recreation and nature conservation play a smaller role than factors related to wood production and forest management as for motives for harvesting energy wood. However, almost a half of forest owners in this study were uncertain of their willingness to supply biomass. This is partly due to limited knowledge of the issues involved in energy wood and agricultural energy crop production and the underdeveloped markets for energy biomass. In order to achieve the targets, supply should be activated by further developing market practices, information, guidance and possibly other incentives for landowners. In general, there is interest among landowners in increasing the supply of energy biomass. However, the growth of supply presumes that production is an economically attractive and competitive alternative, that the markets are better organized than at present, and that more comprehensive information is available about bioenergy and biomass markets and production techniques.

Agricultural Energy Crops and the Search for Alternative Energy: Analysis of the Current Research and Core Journal Literature on Biofuels and Bioenergy

ABSTRACT This paper analyzes the agricultural research output on energy crops and bioenergy for the period 2000–2005. Seven hundred eighty-three (783) articles gathered from CAB s from this period were analyzed to determine which disciplines have been publishing the most on this subject. The findings show that engineering-related research is most prevalent but that twelve distinct agricultural disciplines produced research on the subject during the study period, with varying degrees of productivity for each discipline. The actual agricultural energy resources being researched were determined by examining the 783 articles. The resources were divided into woody crops, non-woody crops, and animal-based resources, and the number of articles for each was tabulated. The three resource types were further examined to create a list of the individual crops or animal-based resources under investigation, along with the number of articles for each individual crop or resource. The core journal literature dealing with energy crops and bioenergy was determined by doing searches in both CAB s and Web of Science and tabulating the number of articles appearing in each journal. This allowed for the creation of a core journal list, ranked by the number of appropriate articles appearing in each journal.

Pflanzenbauliche Aspekte der Energie‐und Stickstoffbilanz des Rapsanbaus

AbstractZur Bewertung landwirtschaftlicher Kulturarten als Energiepflanzen bedarf es eines geeigneten Vergleichsmaßstabes auf energetischer Basis, der die unterschiedliche stoffliche Zusammensetzung der Ernte‐ und Nebenprodukte berücksichtigt. Im Vergleich zwischen Getreidearten (Weizen, Gerste) und der Ölfrucht Raps konnten die höchsten Energiebindungen pro Fläche in der oberirdischen Biomasse von Winterweizen und Winterraps realisiert werden. Das energetisch bewertete Verhältnis zwischen Ernteorgan und Gesamtsprozeß (Energieernteindex) erreicht für beide Kulturarten annähernd gleiche Werte. Die Energiekonzentration verschiedener Pflanzenteile ist kulturartspezifisch ausgeprägt und von der (mineralischen) N‐Düngung nur marginal beeinflußbar. Der Wirkungsgrad der Energiebindung (Energienutzungseffizienz, d. h. die Relation des solaren Energieinputs zur gebundenen Biomassenenergie) weist im Rapsbestand den höchsten Wert auf. Er liegt mit maximal 3.4% allerdings auf einem insgesamt sehr niedrigen Niveau. Die Energiebindung pro Fläche zeigt eine deutliche Abhängigkeit von der mineralischen N‐Düngung, die den Nettoenergiegewinn des gesamten Anbausystems maßgeblich bestimmt. Der energetisch optimale Faktoreinsatz in der Pflanzenproduktion besteht in der Kombination aus einem ertragssichernden Fungizideinsatz und der gleichzeitigen Reduzierung des mineralischen N‐Düngeraufwandes. In diesem Zusammenhang ist die Möglichkeit der Substitution von mineralischen N‐Düngern durch organische Düngemittel in Zukunft noch genauer zu untersuchen.