Giganteus Biomass Research Articles

Maximizing the valorization potential of lignin through optimization of the Soda pulping conditions

The valorization potential of lignin is strongly dependent on the yield that can be obtained during the pulping process as well as its chemical structure. Both of these are determined by factors such as the biomass type, the selected extraction strategy and the employed conditions. Within this study, Miscanthus x giganteus biomass was subjected to systematically varying Soda pulping conditions, i.e., temperature (100 °C – 180 °C), OH– concentration (0.158 mol/L – 1.000 mol/L) and time (60 min – 360 min). These pulping conditions can be combined into a single factor, reflecting the processing severity, which in this work varied from approximately 1 to 5. The resulting black liquor, precipitated lignin, lignin stock solution (i.e., lignin dissolved in the solvent used in the subsequent depolymerization step) and product pool after mild reductive catalytic depolymerization (200 °C, 10 bar H2 initial, 4 h) were thoroughly characterized using a plethora of analysis techniques. Increasing the severity factor of the pulping was found to result in an enhancement of the delignification degree from 25.3 ± 2.6 % to 95.4 ± 9.9 %. However, beyond a severity factor of 3, fragmentation of native ether linkages and condensation reactions start to cause unfavourable changes in the chemical structure of the lignin and depolymerization product pool. Furthermore, these reactions significantly reduce the total mass yield from biomass to depolymerization product pool. An Adaboost model with quadratic base estimator was trained against the experimental data, and subsequently used to optimize the pulping conditions, aiming at a maximum total mass yield with minimal fragmentation and, hence, condensation, of the lignin. The optimum was experimentally validated, which resulted in a lignin with high β-O-4 content (42.7 ± 2.8 linkages per 100 aromatic units) and a total mass yield of 30.9 ± 3.4 wt% and a pulp with a residual lignin content of 8.25 ± 0.94 wt%.

Miscanthus x giganteus biochar: Effective adsorption of pharmaceuticals from model solution and hospital wastewater

This study investigated the adsorption of pharmaceuticals, including atenolol (AT), 17-α-ethinylestradiol (EE2), and sulfamethoxazole (SMX), in model solutions and in the effluent from a hospital wastewater treatment plant. The pharmaceuticals were adsorbed on biochar prepared from Miscanthus x giganteus biomass obtained from the phytoremediation of contaminated or marginal soil. The feedstock was pyrolyzed at 360 °C (M-3) and 500 °C (M-5). The representation of functional groups, specific surface area, porosity, and pore volume were lower for M-5. Pore diameters were comparable, but their depth decreased for M-5. The specific surface area and porosity surface area of M-5 were 30 times higher after 4 h of shaking compared to properties without shaking. The biochar leachate pH was 9.8 ± 1.0 (M-3), and 11.1 ± 1.1 (M-5). No desorption of potentially risk organic compounds was detected. M-3 was generally a better adsorption material. The removal of EE2, AT and SMX was greater than 90%, 70% and 30 % respectively after 4 h in model waters. There was no evidence of a linear relationship between the sorption efficiency of pharmaceuticals and the biochar dose. Sorption experiments with real wastewater from a hospital wastewater treatment plant demonstrated high removal rates of monitored pharmaceuticals, including e.g. SMX (80%), trimethoprim (91%), venlafaxine (100%), clarithromycin (96%), tramadol (93%), diclofenac (86%). It was proven that the efficiency of the adsorption process is influenced not only by the dose or physico-chemical properties of the biochar, but also by the initial concentration of the pharmaceutical and its properties. The presence of other components of real wastewater, which can cause competitive sorption and overlapping of active centers on the surface of the biochar, also decreased the efficiency. The results demonstrate that both biochars are suitable for tertiary or quaternary water treatment for pharmaceutical removal. Due to the lower energetic, and therefore economic, costs of pyrolysis, a lower pyrolysis temperature can be preferred.

Impact of cultivation conditions on physicochemical characteristics of Miscanthus × giganteus biomass

AbstractMiscanthus × giganteus has emerged as a successful energy crop for remediating marginal land, offering potential as an alternative energy source for climate change mitigation. This study aimed to assess the physicochemical properties for gasification of Miscanthus × giganteus biomass from plantations with diverse soil origins, characteristics, contamination levels, age, and climate conditions, aiming to determine their influence on the energy properties. Fuel parameters, i.e.: ash content, volatile matter, calorific value, ultimate analysis, and ash melting behavior were measured. Analysis of biomass samples revealed significant variations in the ash content and volatile matter with the average values of 4.5 and 78.8%, respectively, depending of the produced biomass. The calorific value remained consistently high, ranging from 18 to 19 MJ kg−1, even when biomass was derived from the contaminated soil. Additionally, biomass ash exhibited complete melting at temperatures exceeding 1300 °C, signifying its suitability for gasification without encountering technical obstacles. Employing PCA analysis, the significance of plantation age, location, and soil characteristics in shaping the physicochemical properties of Miscanthus × giganteus biomass for gasification was highlighted. The results illustrated that soil contamination by trace elements had a minimal impact on the physicochemical properties, whereas plantation age and climate conditions significantly influenced to the fuel properties of biomass.

The influence of diesel contaminated soil on Miscanthus x giganteus biomass thermal utilization and pyrolysis products composition

The second-generation energy crop Miscanthus x giganteus (Mxg) demonstrated ability to produce adequate biomass yield even in marginal or contaminated soils. This renewable biomass can be utilized energetically or transformed into various biobased products and thus contribute to decrease of primary resources and fossil fuel use. To evaluate potential effects on energetic biomass properties Mxg was grown in diesel contaminated soils. Traces of total petroleum hydrocarbons were found solely in the leaves, however most likely resulting from air contamination. No differences were detected in the elemental composition of the raw biomass. Biomass combustion heat value reached average of 17.23 ± 0.21 MJ kg−1; contamination-originated leaves had slightly but significantly decreased heat values (14.41 ± 1.10 MJ kg−1) while heat of other parts was comparable to control. Thermogravimetric curves, simulating thermic utilization processes, were comparable both under oxygen (combustion) and nitrogen (pyrolysis). No diesel impacts were observed on the pyrolysis products yield. Higher amounts of CH4, C2H6, C3H4, C3H6 and C3H8 were detected in the pyrolysis gas from aboveground biomass from contaminated soil. Diesel contamination decreased significantly biochar surface. Concentrations of acids and esters in biooil were increased on the expense of concentrations of furans in the case of samples from contaminated soils. No significant effect on phenols and ketones concentrations in the biooil was observed. The amount of acetic acid, as the main biooil component, increased in the above- and below-ground plant parts along with the higher diesel concentrations in soil. Despite slight changes detected, the parameters of the biomass produced in diesel-contaminated soils present no obstacle to its energetic utilization and Mxg can be recommended for productive phytomanagement of such soils.

Enhanced hydrophobic paper-sheet derived from Miscanthus × giganteus cellulose fibers coated with esterified lignin and cellulose acetate blend

Biobased packaging materials derived from carbon-neutral feedstocks are sustainable alternatives to conventional fossil-based polymers. In this study, a method was developed to prepare paper-sheets derived from Miscanthus × giganteus cellulose fibers for potential food contact applications. The papers were hydrophobized with modified lignin from Miscanthus × giganteus biomass and commercial Kraft alkali lignin through hydroxyethylation with ethylene carbonate, followed by esterification with propionic acid. The esterified lignin (10 % w/w) and cellulose acetate (5 % w/w, based on lignin content) were dissolved in acetone and applied as a coating on the miscanthus paper sheets. The esterified lignins were characterized using FTIR, NMR, DSC, TGA, and elemental analyses. The uncoated and coated paper-sheets had contact angle values 52.4° and >130°, respectively, indicating an increased surface hydrophobicity of the coated paper samples. The water vapor transmission rate decreased significantly from 213.7 (uncoated paper-sheet) to 63.3 g/m2.d (coated paper-sheet). The tensile strength of the coated paper (64.6 MPa) was higher than the uncoated counterpart (57.1 MPa). Results from this study suggest that the esterified lignin coated miscanthus paper is a promising hydrophobic food packaging material alternative to conventional fossil-based thermoplastics.

PERSPECTIVES FOR THE USE OF BIOMASS GENERATED BY SOME MISCANTHUS GENOTYPES IN THE PRODUCTION OF DENSIFIED SOLID BIOFUELS

Miscanthus is a Poaceae family perennial crop of C4 bioenergy characterized by the multilateral use potential, including the production of biofuels. The paper aimed to study the opportunity to use the biomass generated by two Miscanthus genotypes: Miscanthus × giganteus and Miscanthus sinensis in the production of densified solid biofuels. We quantified the biomass generated by crops that were 5 years old, harvested from both genotypes after the vegetation period, the year 2020. Samples were taken from the experimental lots of the Alexandru Ciubotaru National Botanical Garden (Institute) from the Republic of Moldova in autumn, immediately after the initial onset of senescence and in spring of the following year, before the start of the growing season. The results showed that the above-ground biomass generated by both Miscanthus genotypes harvested in spring had had significantly higher quality characteristics compared to the biomass harvested in autumn. Virtually all qualitative indices of the Miscanthus × giganteus biomass harvested in spring comply with the requirements of the ENPlus international standards for densified solid biofuels. The Miscanthus sinensis biomass, both, had lower indices than the Miscanthus × giganteus biomass from both qualitative and quantitative points of view and the former can be used as a filler in various mixtures of raw material for the production of solid biofuels.

Biomass yield and quality of the Miscanthus × giganteus in northern China

AbstractMiscanthus × giganteus has attracted much attention and occupied a significant niche as a bioenergy crop to meet the world's energy demand and in the fight against climate change. In this study, a field experiment was conducted to evaluate the yield and biomass characteristics of M. × giganteus over a period of three years from 2013 to 2015 in Beijing, China. M. × giganteus plants showed higher tiller density and litter leaf weight in the third year, whereas no significant difference in plant height was observed among the years. In contrast, a larger number of nodes per plant were recorded in the first year. Biomass yield potential was the highest in the third year (42.3 t ha−1). In addition, plant height (r = .594, p = .042), tiller density (r = .854, p < .01), and number of nodes per plant (r = ‐.589, p = .044) were significantly correlated with biomass yield. Contents of cellulose and lignin were higher in stems, while that of hemicellulose and ash were higher in leaves. M. × giganteus biomass may be used for cellulosic ethanol conversion due to high cellulose and hemicellulose contents and low lignin content and for direct combustion and co‐combustion due to high calorific value (18.5 MJ kg−1). To conclude, our findings indicate that M. × giganteus can be cultivated in northern China as an excellent herbaceous bioenergy crop. Rational utilization of the agronomic characteristics would be helpful to screening and breeding bioenergy grass for promoting bioenergy production in China.

Primary Mechanical Modification to Improve Performance of Miscanthus as Stand-Alone Growing Substrates

Selecting proper mechanical processing can improve performance of miscanthus substrates. We studied the effects of mechanical processing methods on substrate morphology, hydrological properties, pH, and nitrogen immobilization. Miscanthus × giganteus biomass was processed into field chips (FC, forage harvester), shreds (S5, mechanical fraying machine through a 5-mm screen) and chips (C15, C10, C5 and C3, hammermill with screen size of 15, 10, 5, or 3 mm). Processed miscanthus materials were also tested as propagation substrates for Chinese cabbage seedlings. Results showed that particle size distribution of miscanthus substrates formed four groups in ascending order of particle size: C3 < C5 < (C10, C15, S5) < FC. The finer miscanthus substrates had higher water holding capacity following the same groupings in particle size. The hydrophobicity of processed miscanthus was low and reversible, with the increasing order of risk as C3 < C5 < C10, C15 < S5, FC. All miscanthus substrates had similar and low pH buffering capacity. Nitrogen immobilization was similar among miscanthus substrates. The seedlings in miscanthus substrates had similar germination rates but a lower biomass compared to those grown in peat and coir. Primary mechanical modification of miscanthus offers opportunities for different sizes of substrate materials with few changes to the physical or chemical properties tested in this work.

Enhanced microfibrillation of Miscanthus × giganteus biomass by binary-enzymes pre-treatment

Miscanthus, a high yield and low maintenance perennial plant with a high cellulose fiber contents, is a potential feedstock for pulp production. In this study, a binary enzyme cocktail of cellulase and laccase was employed for the extraction of cellulose microfibers from miscanthus biomass. The effect of enzyme concentrations (0.10%, 0.15%, 0.20%, and 0.25%, w/w) for the binary enzymes (cellulase-laccase: 1:1 ratio) pre-treatments on pulp and hand-sheet materials were studied and compared with those prepared from the single enzyme (cellulase or laccase) pre-treatment. The binary enzymes concentration at 0.25% (w/w) showed the maximum extraction yield of cellulose (47.2%, w/w) and lignin (27.9%, w/w). The resulting fibers had 43.7% crystallinity, a degree of polymerization of 1435, a water retention value of 312.7%, and a crystallite size of 23.4 nm. Furthermore, the resulting fibers from binary enzymes concentration at 0.25% (w/w) exhibited a higher thermal stability and fibrillated strands than those obtained from the single enzyme pre-treatment. Hand-sheets developed from the cellulose microfibers extracted by the enzyme cocktail at 0.25% (w/w) enzyme concentration showed higher mechanical properties and water absorption capacity than those prepared from the single enzyme pre-treatment.

Morphological growth pattern of Phanerochaete chrysosporium cultivated on different Miscanthus x giganteus biomass fractions

BackgroundSolid-state fermentation is a fungal culture technique used to produce compounds and products of industrial interest. The growth behaviour of filamentous fungi on solid media is challenging to study due to the intermixity of the substrate and the growing organism. Several strategies are available to measure indirectly the fungal biomass during the fermentation such as following the biochemical production of mycelium-specific components or microscopic observation. The microscopic observation of the development of the mycelium, on lignocellulosic substrate, has not been reported. In this study, we set up an experimental protocol based on microscopy and image processing through which we investigated the growth pattern of Phanerochaete chrysosporium on different Miscanthus x giganteus biomass fractions.ResultsObject coalescence, the occupied surface area, and radial expansion of the colony were measured in time. The substrate was sterilized by autoclaving, which could be considered a type of pre-treatment. The fastest growth rate was measured on the unfractionated biomass, followed by the soluble fraction of the biomass, then the residual solid fractions. The growth rate on the different fractions of the substrate was additive, suggesting that both the solid and soluble fractions were used by the fungus. Based on the FTIR analysis, there were differences in composition between the solid and soluble fractions of the substrate, but the main components for growth were always present. We propose using this novel method for measuring the very initial fungal growth by following the variation of the number of objects over time. Once growth is established, the growth can be followed by measurement of the occupied surface by the mycelium.ConclusionOur data showed that the growth was affected from the very beginning by the nature of the substrate. The most extensive colonization of the surface was observed with the unfractionated substrate containing both soluble and solid components. The methodology was practical and may be applied to investigate the growth of other fungi, including the influence of environmental parameters on the fungal growth.

CHARACTERISTICS OF PULP OBTAINED FROM MISCANTHUS x GIGANTEUS BIOMASS PRODUCED IN LEAD-CONTAMINATED SOIL

"The main goal of the study was to investigate processing of Miscanthus x giganteus biomass produced in soil contaminated with lead and other trace elements (TEs) into pulp using chemical pulping. The phytoremediation parameters of the plant were measured during two growing seasons, which confirmed that the process can be defined as phytostabilization; the contaminants were mainly concentrated in the roots and practically did not translocate to the stalks and leaves, which permitted the use of the aboveground biomass to process into pulp using the organosolvent cooking. The chemical composition, morphological structure, and microscopic characteristics of various crops’ stalks were investigated and compared with the same parameters received for wood and other non-wood plant materials: rape, flax, hemp, and wheat straw. Indicators of pulp were studied depending on the duration of the organosolvent cooking. After 90 minutes of the cooking process, the peroxide pulp from M. x giganteus had a breaking length of 8300 m, tear resistance of 310 mN, and burst resistance of 220 kPa, testifying the high values of the indicators. Further research should investigate the properties of pulp produced from M. x giganteus biomass grown in soils contaminated with various TEs, as well as the possible translocation of elements to pulp."

The Influence of Three Years of Supplemental Nitrogen on Above- and Belowground Biomass Partitioning in a Decade-Old Miscanthus × giganteus in the Lower Silesian Voivodeship (Poland)

Because of the different opinions regarding nitrogen (N) requirements for Miscanthus × giganteus biomass production, we conducted an experiment with a set dose of nitrogen. The objective of this study was to examine the effects of nitrogen fertilization on the biomass yield, water content, and morphological features of rhizomes and aboveground plant parts in various terms during a growing season over the course of three years (2014–2016) in Lower Silesia (Wroclaw, Poland). The nitrogen fertilization (dose 60 kg/ha and control) significantly affected the number of shoots (p = 0.0018), the water concentration of rhizomes (p = 0.0004) and stems (p = 0.0218), the dry matter yield of leaves (p = 0.0000), and the nitrogen uptake (p = 0.0000). Nitrogen fertilization significantly affected the nitrogen uptake in all plant parts (p = 0.0000). Although low levels of nitrogen appeared to be important in maintaining the maximum growth potentials of mature Miscanthus × giganteus, the small reductions in the above- and belowground biomass production are unlikely to outweigh the environmental costs of applying nitrogen. More studies should use the protocols for the above- and belowground yield determination described in this paper in order to create site- and year-specific fertilizer regimes that are optimized for quality and yield for autumn (green) and spring (delayed) harvests.

Quantifying the peak yields of four cellulosic bioenergy crops in the East-Central Poland.

Through the six successive years (2010–2015), from the 5th to the 10th year of cultivation, research was carried out on yielding and species characteristics of 4 perennial vegetatively propagated energy crops. These were: 2 species of Miscanthus, Sida hermaphrodita, and 2 Salix viminalis clones (1047 and 1054), cultivated side-by-side. The height and shoot number, yield and biomass moisture were evaluated. The highest shoot density of Miscanthus sacchariflorus was found, while the largest yield of Miscanthus × giganteus. Salix viminalis and Miscanthus × giganteus biomass was characterized by the highest content of accumulated moisture (on average 50%). The Sida hermaphrodita plants were appeared as the tallest ones on the six-year average. It is worth mentioning, we have concluded that yield of Miscanthus, and Sida is high and stable in the long-term study. However, in the average yields of these 2 species (Miscanthus × giganteus and Sida hermaphrodita) no statistically significant differences were found. Results can strengthen the improved species diversity in perennial energy crops cultivation.

Calorific values of Miscanthus x giganteus biomass cultivated under suboptimal conditions in marginal soils

Calorific values of Miscanthus x giganteus biomass cultivated under suboptimal conditions in marginal soils

Sustavi žetve biomase Miscanthus x giganteusa: Pregled

The agricultural biomass classification includes the biomass obtained from fast growing energy crops. One of these crops is the perennial grass Miscanthus x giganteus, which after the third and fourth year of plantation forms a high-density stand with exceptionally high and firm shoots. Thus, special emphasis should be put on the harvesting systems. For Miscanthus harvesting, haymaking and silage making machinery is mainly used by applying single-phase or multi-phase techniques. The aim of this paper is to give an overview of the Miscanthus x giganteus biomass harvesting systems with regard to the form of harvested biomass, either shredded or/and baled biomass. In addition to application of fertilizers, biomass harvest is the only agro-technical measure that is used when a plantation reaches full maturity and it should be applied with the lowest possible energy input and biomass loss. Due to increased interest in production of energy from Miscanthus x giganteus biomass, the existing machinery is being adjusted to these new requirements and new specialised machines are being developed.

Studies of CO2 gasification of the Miscanthus giganteus biomass over Ni/Al2O3-SiO2 and Ni/Al2O3-SiO2 with K2O promoter as catalysts

An assessment of the catalytic and non-catalytic gasification process of the Miscanthus giganteus (MG) biomass in an atmosphere of carbon dioxide was performed on the basis of thermogravimetric and thermovolumetric analyses. In the first step, the thermal behavior of biomass was determined by analyzing the mass loss during non-catalytic gasification with the use of TGA. The results of thermogravimetric analysis were used to assess the course of the biomass heating process in the atmosphere of CO2 and to distinguish the individual phases of this process. Then, the thermovolumetric measurements of MG gasification were taken with the use of Ni/Al2O3-SiO2 and Ni/Al2O3-SiO2 with K2O promoter as catalysts. The obtained results allowed determining the process rate as well as composition of the resulting gas and yields of main gaseous products (CH4, CO, H2). The use of Ni/Al2O3-SiO2 as catalyst resulted in the highest conversion rate of MG gasification into gaseous products with considerably increased contents of H2 and CO. The second analyzed catalyst—Ni/Al2O3-SiO2 with K2O promoter—did not catalyze the gasification process. However, the use of both tested catalysts had a positive effect on reducing the methane content in the resulting gas. One can also suppose that it promotes the decomposition of the tar formed in the process.

The comparison of single and double cut harvests on biomass yield, quality and biogas production of Miscanthus × giganteus

The aim of the research was to determine the impact of double-cut harvest system on yield, as well as on suitability of Miscanthus × giganteus biomass for ensiling and biogas production. Biomass was harvested at the end of June (harvest I) and at the beginning of October (harvest II, regrowth). A single-cut regime at the end of October was also conducted. Biomass from harvests I and II was ensiled and subjected to anaerobic fermentation. The total dry matter (DM) yield from double-cut harvest system was similar to the DM yield from one-cut harvest, but two harvests per year had a positive effect on chemical composition of the biomass. C/N ratio and lignin content in the biomass from harvest I was lower compared to the single-cut biomass. Double harvest biomass was susceptible to ensiling, however, the biomass from harvest I characterized by low dry matter and water soluble sugars content resulted in poorer quality of the obtained silage (butyric acid was present). There were no significant differences between the methane yields obtained from ensiled biomass from harvests I and II.

Impact of plant growth regulators and soil properties on Miscanthus x giganteus biomass parameters and uptake of metals in military soils.

The impact of plant growth regulators (PGRs) "Stimpo" and "Regoplant" on Miscanthus x giganteus (Mxg) biomass parameters was investigated when the plant was grown in military soils with different properties from Dolyna, Ukraine and Hradcany, Czech Republic. The results showed that PGRs positively influenced the biomass parameters when the plant was grown in soil in Dolyna with good agricultural characteristics, the influence of "Regoplant" was higher and the best results were obtained with combined treatment: application to rhizomes before planting and spraying on the biomass during vegetation. Using of PGRs did not improve the biomass parameters when the plant was grown in poor soil in Hradcany. In parallel the peculiarities of the metals uptake process were studied for the following metals: chromium (Cr), manganese (Mn), nickel (Ni), copper (Cu), zinc (Zn), strontium (Sr) and lead (Pb). The uptake behavior of the monitored elements differed based on the soil quality. According to the bioconcentration factor uptake of the abiogenic elements, Cr and Pb, was dominant in the plant roots in both soils, whereas Ni was not detected in any plant tissues. The behavior of biogenic elements (Mn, Cu, Zn) and their analogs (Sr) was different. Those elements were more intensively taken up in shoot tissues in low-nutrient sandy Hradcany soils, while they were mainly taken up in plant roots in fertile Dolyna soils. The unusual behavior of biogenic elements in the low-nutrient soils may be explained by the effect of stress. However, more research is needed focused mainly on soil properties and nutrient availability in order to confirm or disprove this hypothesis and to explore the cause of the stress. The summarized results here show that soil properties influenced Mxg biomass parameters, affected the uptake behavior of metals significantly and tested PGRs cannot be utilized universally in the production of Mxg in the poor military soils.

Kinetic study of the pyrolysis and gasification of Rosa multiflora and Miscanthus giganteus biomasses via thermogravimetric analysis

The thermal behaviour of the Rosa multiflora (3 groups: control, irradiated 3 × 3 seconds, and 3 × 9 seconds by low power laser of wavelength 672 nm) and Miscanthus giganteus (3 groups: R, V, and Z) biomass by thermogravimetric analysis (TGA) was studied at heating rate 3 K per minute from ambient temperature to 950°C. The TGA tests were performed in high purity CO2 (99.998%) with a flow rate 200 mL per minute and 100 mg of sample, milled and sieved to a particle size below 250 μm. In contrast to the majority of the conducted examinations, which are carried out with the use of chars, the measurements were conducted for raw biomass. The kinetics parameters of the biomass conversion process were determined from the experimental data by integral methods (Murray and White; Senum and Yang). The methods used have allowed distinguishing and analysing the different stages of the process, i. e. the primary and secondary pyrolysis as well as gasification. Both methods gave comparable results. The activation energy determined using more accurate Senum and Yang method ranged from 85-88 kJ/mol (primary pyrolysis), from 29-32 kJ/mol (secondary pyrolysis), and from 173-190 kJ/mol (gasification) for Rosa multiflora biomass and from 86-111 kJ/mol (primary pyrolysis), from 22-25 kJ/mol (secondary pyrolysis), and from 181-217 kJ/mol (gasification) for Miscanthus giganteus. The pre-exponential factor was in the range of 5.95 ⋅ 106 to 13.05 ⋅ 106 min–1 (primary pyrolysis), 2.25-4.22 min–1 (secondary pyrolysis), and 13.96 ⋅ 106 to 1.18 ⋅ 108 min–1 (gasification) for Rosa multiflora biomass and 6.94 ⋅ 106 to 1.79 ⋅ 109 min–1 (primary pyrolysis), 0.88-1.62 min–1 (secondary pyrolysis), and 131.54 ⋅ 106 to 1.92 ⋅ 109 min-1 (gasification) for Miscanthus giganteus biomass.

Nitrogen Fertilization Effects on Biomass Production and Yield Components of Miscanthus ×giganteus.

Grasses such as Miscanthus ×giganteus and Panicum virgatum (switchgrass) can potentially be used to produce bioenergy on a large scale in the Midwestern USA. The biomass productivity of these warm-season perennial grasses, particularly M. × giganteus, can be substantial, even when grown with limited inputs. The literature, however, varies regarding the nitrogen requirements for M. ×giganteus biomass production. In addition, there is a lack of information that identifies the yield-component(s) (including total tiller number, tiller weight, total tiller diameter, total tiller height, phytomer number, reproductive tiller number, vegetative tiller number, reproductive tiller height, vegetative tiller height, reproductive tiller diameter, vegetative tiller diameter, and reproductive tiller phytomer number) that contributes to M. ×giganteus biomass yields. Thus, the objective of this study was to examine the effects of fertilization on biomass yield and individual M. × giganteus plant-yield components. Plots of M. ×giganteus were planted in 2008 in Urbana, IL, USA, and received annual applications of 0, 60, or 120 kg N ha-1. M. ×giganteus productivity increased when nitrogen was applied; between 2011 and 2014, nitrogen applications of 60 or 120 kg N ha-1 produced average annual yields of 22.0 dry Mg ha-1 compared to 11.8 dry Mg ha-1 for unfertilized M. ×giganteus. Both the total number of tillers per m2 and the tiller weight also increased as N-application rates increased. Our results indicate that increased reproductive tiller density and tiller weight with increased N fertilization increased M. ×giganteus biomass yield.