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[en] Highlights: • Two processing routes using green solvents were used to fractionate Miscanthus. • Purified cellulose fibres were analysed using physicochemical & statistical tools. • Different processes generated fibres with different physicochemical properties, which impacted in downstream processing. - Abstract: Using a biorefinery approach, biomass polymers such as lignin and carbohydrates can be selectively purified from lignocellulosic feedstocks with the aim of generating not only lignocellulosic bioethanol but also high value bio-based compounds. Furthermore, the efficient use of the entire biomass can increase overall feedstock value and significantly contribute to process cost-effectiveness. Therefore, the aim of this work was to fractionate the main compounds of the energy crop Miscanthus x giganteus (MxG) using ‘green’ solvents in order to obtain cellulose-enriched fibres as well as non-toxic streams rich in hemicellulose and lignin. Two processing routes were compared: a direct 1-step modified organosolv method for simultaneous lignin and hemicellulose removal; and a 3-step sequential process using subcritical water extraction for recovery of first extractives then hemicellulose, followed by modified organosolv lignin extraction. Both methods successfully generated cellulose-enriched fibres; from a complex mixture of compounds present in MxG, it was possible to obtain fibres comprising 78% cellulose without the use of commonly-applied toxic solvents that can potentially limit end uses for processed biomass and/or need additional neutralization steps. Fibres generated by the direct and sequential processes were very similar in composition; however, physicochemical analysis of the fibres using scanning electron microscopy, Fourier-transform infrared spectroscopy and principal component analysis confirmed structural differences resulting from the two processing routes, which were demonstrated to have an impact on downstream processing.
[en] The cultivation of energy crops on landfills represents an important challenge for the near future, as the possibility to use devalued sites for energy production is very attractive. In this study, four scenarios have been assessed and compared with respect to a reference case defined for northern Italy. The scenarios were defined taking into consideration current energy crops issues. In particular, the first three scenarios were based on energy maximisation, phytotreatment ability, and environmental impact, respectively. The fourth scenario was a combination of these characteristics emphasised by the previous scenarios. A multi-criteria analysis, based on economic, energetic, and environmental aspects, was performed. From the analysis, the best scenario resulted to be the fourth, with its ability to pursue several objectives simultaneously and obtain the best score relatively to both environmental and energetic criteria. On the contrary, the economic criterion emerges as weak, as all the considered scenarios showed some limits from this point of view. Important indications for future designs can be derived. The decrease of leachate production due to the presence of energy crops on the top cover, which enhances evapotranspiration, represents a favourable but critical aspect in the definition of the results.
[en] Highlights: • Effective and simple regeneration system of three Miscanthus spp. was developed. • Efficiency for M. sinensis and M. × giganteus was about 20 plants per explant. • Micropropagation rate for M. sacchariflorus was as high as 6.7 plants per explant. • Potential scale of direct production is 1500–- 2000 seedlings from a donor clump. - Abstract: Miscanthus species are important energy crops, due to their high yield of biomass, used for combustion, biofuel fabrication and as a feedstock for various products. They can be also utilised for phytoremediation and other ecological programmes. Extensive needs require considerable amounts of planting material, which can be provided by in vitro micropropagation. A new effective and simple regeneration system of M. sinensis, M. × giganteus and M. sacchariflorus was developed, which comprises just two media supplemented exclusively with growth regulators and lasts for 5 months. Significant differences in regeneration capacity were observed between species, genotypes, and initial explants, and also in the effects of media and growth regulators. Embryogenic callus was induced on explants excised from whole immature inflorescences for M. sinensis and M. × giganteus, or inflorescence axes for M. sacchariflorus, implanted on C17 medium with 90 g l−1 maltose, 5.0 mg l−1 2,4-D and 0.5 mg l−1 BAP. Plant regeneration, tillering, and rooting were conducted on 190-2 medium with 30 g l−1 sucrose, 0.5 mg l−1 KIN and 0.5 mg l−1 NAA. The system produces about 7–20 plantlets per a single explant depending on responsiveness of a genotype of M. sinensis, M. × giganteus and M. sacchariflorus. This indicates the potential scale of direct production at 1500–2000 plantlets from a donor clump. The presented system may provide a large number of plants for field trials and physiological research, as well as facilitate the application of biotechnological methods to improve utility traits of bioenergy crops.
[en] Primary energy mix in Kosovo with 98 % consisting of lignite and only 2 % of water is far from portfolio of primary energy sources which could contribute to a sustainable and environmental friendly energy supply of the country. In order to improve the situation, government is supporting activities in favor of upgrading of electricity production capacities based on Renewable Energy Sources. Corresponding action plans and feed in tariffs are already in place. However, prior to any investment, one needs specific results on available potential. Current study provides results of the analysis of Kosovo potential for energy production by using of agricultural crops. Study is based on national statistics on available agricultural crops in Kosovo and provides results on biomass potential of crops, corresponding energy potential and an assessment of financial cost of energy produced.
[en] After a year of doubt and decline the consumption of bio-fuel resumed a growth in 2014 in Europe: +6.1% compared to 2013, to reach 14 millions tep (Mtep) that is just below the 2012 peak. This increase was mainly due to bio-diesel. By taking into account the energy content and not the volume, the consumption of bio-diesel represented 79.7% of bio-fuel consumption in 2014, that of bio-ethanol only 19.1% and that of biogas 1%. The incorporating rate of bio-fuels in fuels used for transport were 4.6% in 2013 and 4.9% in 2014. The trend is good and the future of bio-fuel seems clearer as the European Union has set a not-so-bad limit of 7% for first generation bio-fuels in order to take into account the CASI effect. The CASI effect shows that an increase of the consumption of first generation bio-fuels (it means bio-fuels produced from food crops like rape, soy, cereals, sugar beet,...) implies in fact a global increase in greenhouse gas release that is due to a compensation phenomenon. More uncultivated lands (like forests, grasslands, bogs are turned into cultivated lands in order to compensate lands used for bio-fuel production. In most European countries the consumption of bio-diesel increased in 2014 while it was a bad year for the European industry of ethanol because ethanol prices dropped by 16 %. Oil companies are now among the most important producers of bio-diesel in Europe.
[en] Present article is devoted to zinc comprising coordination compounds as growth stimulants of cotton seeds. The influence of zinc coordination compounds with physiologically active ligands on germinative energy and seed germination of cotton was studied. The biogical activity and effectiveness of zinc comprising coordination compounds at application them for humidification of cotton seeds was studied as well.
[en] With a vast area of marginal land, the Loess Plateau of China is a promising region for large-scale production of second-generation energy crops. However, it remains unknown whether such production is sustainable in the long run, especially under climate change. Using a regional climate change model, PRECIS, we analyzed the impact of climate change on Miscanthus production in the Loess Plateau. Under three emission scenarios, A2, B2, and A1B, both the average yield and total area capable of supporting Miscanthus production would increase continuously in the future period (2011–2099). As a result, the total yield potential in the region would increase by about 20% in this future period from the baseline period (1961–1990). This was explained primarily by predicted increases in temperature and precipitation across the Loess Plateau, which improved the yield of the perennial C4 plants relying exclusively on rainfed production. The areas that are currently too dry or too cold to support Miscanthus production could be turned into energy crop fields, especially along the arid–semiarid transition zone. Thus the Loess Plateau would become increasingly desirable for growing second-generation energy crops in this century, which could in turn contribute to soil improvement and ecological restoration of the region. (letter)
[en] Highlights: • Farmers' willingness to grow and use land for oilseeds production is geographically dependent. • 58% of farmers surveyed were willing to grow different varieties of oilseeds for bio-energy production. • Farmers were willing to contribute 160 acres on average for bio-energy production. • A nearby crushing facility and technical information increase adoption of oilseed crops. - Abstract: The purpose of this paper is to determine farmers' willingness to adopt and allocate land for growing non-food oilseeds as bio-energy crops across the western US. A mail survey was conducted in three regions of the western US from randomly selected wheat farmers. Data was analyzed using Heckman's two stage selection model to correct for selection bias. Under favorable contracts, the study found that 58% of sample farmers were willing to adopt oilseeds as bio-energy crops and initially contribute an average of 160 acres of land for production per farm. Concerning farmers' adoption decisions, factors such as experience growing oilseed crops, availability of a nearby crushing facility, use of no till, being a first adopter and having a college degree positively affected adoption, while risk behavior, farm experience and gender negatively affected adoption. With regard to the land allocation decision, factors such as farm income and gender positively affected land allocation decisions, whereas percentage of land rented on a crop share basis, profit ratio (wheat/canola) and livestock ownership negatively affected land allocation decisions.
[en] The idea of using less productive or “marginal land” for energy crops is promoted as a way to overcome the previous land use controversies faced by biofuels. It is argued that marginal land use would not compete with food production, is widely available and would incur fewer environmental impacts. This term is notoriously vague however, as are the details of how marginal land use for energy crops would work in practice. This paper explores definitions of the term “marginal land” in academic, consultancy, NGO, government and industry documents in the UK. It identifies three separate definitions of the term: land unsuitable for food production; ambiguous lower quality land; and economically marginal land. It probes these definitions further by exploring the technical, normative and political assumptions embedded within them. It finds that the first two definitions are normatively motivated: this land should be used to overcome controversies and the latter definition is predictive: this land is likely to be used. It is important that the different advantages, disadvantages and implications of the definitions are spelled out so definitions are not conflated to create unrealistic expectations about the role of marginal land in overcoming biofuels land use controversies. -- Highlights: •Qualitative methods were used to explore definitions of the term “marginal land”. •Three definitions were identified. •Two definitions focus on overcoming biomass land use controversies. •One definition predicts what land will be used for growing biomass. •Definitions contain problematic assumptions
[en] Highlights: • Landowners who own marginal lands are more likely to supply energy crops and required a lower WTA price. • Switchgrass is the crop that landowners are most familiar with and likely to adopt. • Land use for non-production activities can compete with bioenergy crop plantations for marginal lands. - Abstract: A major critique of large scale biomass production is the land competition between food and energy crops. A commonly suggested solution is to limit energy crop production to marginal lands. Physical marginality is often used when discussing marginal lands. However, as important is the socioeconomic marginality. This research fills this gap by evaluating willingness to supply bioenergy crops for landowners who have marginal lands. We conducted contingent valuation surveys at study sites with three model crops: switchgrass, miscanthus and willow. Random utility theory is applied to evaluate factors influencing decision maker's choice to plant energy crops. The results indicate that landowners who own marginal lands are more likely to plant energy crops and they require a lower willingness to accept price compared with landowners who do not have marginal lands. At the same time, we noticed that landowners are unfamiliar with these new crops. Economic concerns are the top reasons preventing them from planting energy crops.