Miscanthus X Giganteus Research Articles

Torrefaction as a Way to Remove Chlorine and Improve the Energy Properties of Plant Biomass

This study characterizes and compares the physicochemical parameters of three types of biomass: giant miscanthus, wheat straw, and white willow. An analysis of the chlorine content in the biomass was determined using a 5E-FL2350 fluorine and chlorine analyzer. In addition, energy parameters characterizing the biomass were determined, such as the content of ash and volatile matter in the tested materials, using the LECO TGA 701 thermogravimetric analyzer. The carbon and hydrogen contents were tested using the LECO TruSpec CHN elementary organic analyzer. The calorific value was determined using the LECO AC 500 isoperibolic calorimeter. Based on the research results, it was concluded that the use of the biomass torrefaction process improves its energy parameters. In the long term, this will affect the maintenance of the technical and operational efficiency of devices, installations, and power boilers compared to the co-combustion of fresh biomass. The greatest differences in results were recorded in the case of chlorine content. Carrying out detailed tests on the material immediately after its harvest showed that the content of this element was about 70% higher than in the case of torrefied raw material. The presence of chlorine in alternative fuels is responsible for the formation of chloride corrosion. Its content can be up to five times higher compared to conventional energy sources. The degree of risk of chloride corrosion of the selected elements of devices and installations is assessed on the basis of the so-called “chlorine corrosion index”.

In-situ catalytic upgrading of bio-oils from rapid pyrolysis of torrefied giant miscanthus (Miscanthus x giganteus) over copper‑magnesium bimetal modified HZSM-5

In this study, fast pyrolysis of both raw and torrefied giant miscanthus (GM) is investigated in detail. It is found that the pyrolysis of torrefied GM results in higher distribution of phenols and aliphatic compounds in bio-oil with lower moisture content. To further improve the bio-oil quality, catalytic upgrading process of the bio-oil from the torrefied GM over copper‑magnesium (CuMg) bimetal doped zeolites is also investigated. As a result, a highest yield of aromatic hydrocarbons of 63.1% favoring in higher monoaromatic hydrocarbons such as benzene, toluene and xylene in the upgraded bio-oil is obtained as GM-300 is used as feedstock and HSZ-Cu 2:1 Mg as the catalyst. It is found that CuMg doping can not only enhance catalytic activity of zeolite but also maintain relatively low coke deposition and improve the catalyst reusability. Besides, the spent catalysts are easily regenerated only by a facile calcination way, and the regenerated catalyst shows almost the same activity as the initial one.

Nitric acid-alkali two-stage pulping of wheat straw, industrial hemp, and Miscanthus x giganteus

Index levels of the process of pulping wheat straw (WS), industrial hemp stalks (HS), and Miscanthus × giganteus (MS) using the nitric acid-alkali (NA−A) method (HNO3/KOH and HNO3/NH4OH two-stage sequential delignification systems) were determined. The research showed, as a rule, a lower total yield of NA−A pulps than kraft pulps from WS, HS, and MS, and a lower level of the tensile index and tear resistance compared to the properties of soda-AQ and kraft pulps presented in other studies, as well as the author’s own studies. Additionally, the levels of nitrogen (in different forms) and potassium in the combined post-pulping filtrate were determined. Their levels were found to be higher than in the fertilizer solution used to fertilize tomato crops grown on soilless substrates in greenhouses. However, application of filtrates from pulping of nonwoody plant straw using NA-A method requires determining the effectiveness of this type of fertilizer solution, its impact on the horticulture and agriculture plants, and the properties of their output including grains, tubers, and fruits.

Climate cooling benefits of cellulosic bioenergy crops from elevated albedo

AbstractChanges in land surface albedo can alter ecosystem energy balance and potentially influence climate. We examined the albedo of six bioenergy cropping systems in southwest Michigan USA: monocultures of energy sorghum (Sorghum bicolor), switchgrass (Panicum virgatum L.), and giant miscanthus (Miscanthus × giganteus), and polycultures of native grasses, early successional vegetation, and restored prairie. Direct field measurements of surface albedo (αs) from May 2018 through December 2020 at half‐hourly intervals in each system quantified the magnitudes and seasonal differences in albedo (∆α) and albedo‐induced radiative forcing (RF∆α). We used a nearby forest as a historical native cover type to estimate reference albedo and RF∆α change upon original land use conversion, and a continuous no‐till maize (Zea mays L.) system as a contemporary reference to estimate change upon conversion from annual row crops. Annually, αs differed significantly (p < 0.05) among crops in the order: early successional (0.288 ± 0.012SE) >> miscanthus (0.271 ± 0.009) ≈ energy sorghum (0.270 ± 0.010) ≥ switchgrass (0.265 ± 0.009) ≈ restored prairie (0.264 ± 0.012) > native grasses (0.259 ± 0.010) > maize (0.247 ± 0.010). Reference forest had the lowest annual αs (0.134 ± 0.003). Albedo differences among crops during the growing season were also statistically significant, with growing season αs in perennial crops and energy sorghum on average ~20% higher (0.206 ± 0.003) than in no‐till maize (0.184 ± 0.002). Average non‐growing season (NGS) αs (0.370 ± 0.020) was much higher than growing season αs (0.203 ± 0.003) but these NGS differences were not significant. Overall, the original conversion of reference forest and maize landscapes to perennials provided a cooling effect on the local climate (RFαMAIZE: −3.83 ± 1.00 W m−2; RFαFOREST: −16.75 ± 3.01 W m−2). Significant differences among cropping systems suggest an additional management intervention for maximizing the positive climate benefit of bioenergy crops, with cellulosic crops on average ~9.1% more reflective than no‐till maize, which itself was about twice as reflective as the reference forest.

Effects of diclofenac, sulfamethoxazole, and wastewater from constructed wetlands on Eisenia fetida: impacts on mortality, fertility, and oxidative stress.

Soil contamination with micropollutants is an important global problem and the impact of these pollutants on living organisms cannot be underestimated. The effects of diclofenac (DCF) and sulfamethoxazole (SMX), their mixture (MIX), and wastewater containing these drugs on the mortality and reproduction of Eisenia fetida were investigated. The impact on the activities of antioxidant enzymes in earthworm cells was also assessed. Furthermore, the influence of the following parameters of the vertical flow constructed wetlands on wastewater toxicity was investigated: the dosing system, the presence of pharmaceuticals and the plants Miscanthus giganteus. The compounds and their mixture significantly affected the reproduction and mortality of earthworms. The calculated values of LC50,28 days values were 3.4 ± 0.3 mg kg-1 for DCF, 1.6 ± 0.3 mg kg-1 for SMX, and 0.9 ± 0.1 mg kg-1 for MIX. The EC50 (reproduction assay) for DCF was 1.2 ± 0.2 mg kg-1, whereas for SMX, it was 0.4 ± 0.1 mg kg-1, and for MIX, it was 0.3 ± 0.1 mg kg-1, respectively. The mixture toxicity index (MTI) was calculated to determine drug interactions. For both E. fetida mortality (MTI = 3.29) and reproduction (MTI = 3.41), the index was greater than 1, suggesting a synergistic effect of the mixture. We also observed a negative effect of wastewater (raw and treated) on mortality (32% for raw and 8% for treated wastewater) and fertility (66% and 39%, respectively) of E. fetida. It is extremely important to analyze the harmfulness of microcontaminants to organisms inhabiting natural environments, especially in the case of wastewater for irrigation of agricultural fields.

Co-culture between Miscanthus x giganteus and Trifolium repens L. to enhance microbial activity, biomass and density in a PAH contaminated technosol

Phytoremediation is a biological soil remediation technique using plants and their associated microorganisms to clean-up contaminated soils and improve soils’ quality. We tested whether a co-culture between Miscanthus x giganteus (MxG) and Trifolium repens L. would enhance the soil biological quality. The objective was to determine the influence of MxG in mono- and in co-culture with white clover on the soil microbial activity, biomass and density. MxG was tested in mono- and in co-culture with white clover in a mesocosm over 148 days. The microbial respiration (CO2 production), the microbial biomass and the microbial density of the technosol were measured. Results showed that MxG induced an increase in microbial activity in the technosol compared to the non-planted condition with the co-culture having a greater impact. Regarding the bacterial density, MxG in mono- and in co-culture significantly increased the 16S rDNA gene copy number. The co-culture increased the microbial biomass, the fungal density and stimulated the degrading bacterial population, contrary to the monoculture and the non-planted condition. We can conclude the co-culture between MxG and white clover was more interesting than MxG monoculture in regards to the technosol biological quality and its potential for PAH remediation improvement.

Economically justified technological map of the cultivation of giant miscanthus (on the example of the Kaluga region)

Relevance. Recently, the demand for paper of non-wood origin has increased. One of such sources is a perennial herbaceous plant Miscanthus giganteus from the bluegrass family.Methods. The technology of growing giant miscanthus was developed by scientists of the Kaluga Research Institute. The study was conducted in accordance with generally accepted methods and recommendations of leading technological and economic research institutes. Technological maps are calculated on the basis of the methods of M.A. Bunkov, V.M. Golovach, as well as E.V. Fastov, O.A. Kovalenko, N.G. Belova. The economic component of miscanthus production is calculated based on the methods of V.R. Boev and I.G. Ushachev.Results. During the calculations, it was found that the production of 1 ton of giant miscanthus straw according to the proposed production technology, with a planned yield of 15 tons/ha, will require 1,370 rubles. In the third year of using crop cultivation, the profitability of production, depending on the studied yield parameters (10, 15, 20 c/ha) is, respectively, 94,6%, 192,0%, 287,2%. The payback period of the project is five to eight years.

Productivity of giant miscanthus plantations depending on the applied elements of cultivation technology in the conditions of the Forest Steppe of Ukraine

Purpose. To improve the technology of caring for giant miscanthus plantations, starting from the second year of the crop vegetation, and to establish the peculiarities of the formation of biomass yield with the use of different types of fertilizers. Methods. The research was carried out in the years 2020–2021 in the conditions of the Bila Tserkva Experimental and Breeding Station of the Institute of Bioenergy Crops and Sugar Beet of the National Academy of Agrarian Sciences located in the zone of unstable moisture of the Right Bank Forest Steppe of Ukraine. The design of the experiment involved the application of mineral fertilisers (ammonium nitrate N24 kg/ha a. i., ammonium nitrate + ammonium sulfate N24 + S6 kg/ha a. i.) in row in the spring, foliar application of humates (Vermisol, 8.0 l/ha, Humifield VR-18, 0.4 l/ha), and complex fertiliser with amino acids (Quantum Aminomax, 0.5 l/ha). Mineral fertilizers were applied locally in row before the emergence of miscanthus seedlings. Split foliar application of humates and amino acids was carried out in the five-leaf stage and two weeks later. Results. Productivity of miscanthus plants differed significantly over growing seasons, while the main regularities of the influence of the investigated elements of plantation care technology on the productivity formation were maintained. In the second year of vegetation (2020), each plant formed from 18 to 37 shoots and in the third year from 37 to 50 shoots. Four-year-old plants had 28–50 shoots each. The yield of raw biomass at the end of the growing season in 2020 varied from 14.5 to 43.5 t/ha. Compared to 2020, in 2021 the biomass yield increased 1.5–2 times – up to 31.0–74.6 t/ha. According to the experiment, the average yield of biomass for the fourth year of the growing was 17% lower compared to the respective indicators of 2021 and varied according to the experiment treatments from 25.3 to 67.1 t/ha. The yield of dry matter varied from 9.78 to 28.30 t/ha in 2020, from 17.50 to 37.85 t/ha in 2021, and from 12.11 to 32.46 t/ha in 2022. The estimated energy output from miscanthus biomass, depending on the influence of the experimental factors, was 174.8–509.6 GJ/ha in 2020, 315.5–683.2 GJ/ha in 2021, and in 2022 – 219.0–587.3 GJ/ha. Conclusions. The minimum values of all studied productivity indicators of miscanthus were obtained in the control treatment of the experiment. Application of ammonium nitrate (N24) and ammonium nitrate with ammonium sulfate (N24 + S6) in spring contributed to a significant increase in the number of shoots per plant, as well as biomass yield and estimated energy yield per hectare. Similarly, significant increase in all indicators of productivity was ensured by foliar application of humates (Humifield BP-18, 0.4 l/ha and Vermisol, 8,0 l/ha). In general, over the years of research, the maximum indicators of the number of shoots per plant, the yield of biomass and the estimated energy output from biomass were obtained under the combined application of mineral fertilisers [ammonium nitrate + ammonium sulfate (N24 + S6)] with two-time foliar application of humates (Vermisol, 8.0 l/ha or Humifield VR-18, 0.4 l/ha) and complex fertiliser Quantum Aminomax, 0.5 l/ha.

ВИКОРИСТАННЯ БІОЧАРУ І МІСКАНТУСУ ГІГАНТСЬКОГО (MISCANTHUS GIGANTEUS) ДЛЯ РЕМЕДІАЦІЇ ҐРУНТУ, ЗАБРУДНЕНОГО НАФТОПРОДУКТАМИ

The dynamics of changes in the chemical composition of soils contaminated with oil products during the vegetation of Miscanthus giganteus, as well as under the conditions of adding biochar (biochar) were studied. The possibility of using the culture of Miscanthus giant and biochar for soil remediation under conditions of oil pollution was analyzed. It was shown that the introduction of biochar into the soil enriched it with nitrate nitrogen, which was actively assimilated by giant miscanthus plants during the growing season. The absorption of nitrate anions by plants was especially active in the second series of the experiment, when the soil + biochar was contaminated with diesel fuel. It was established that the content of NH4+ ions in both series of the experiment increased until the end of the growing season. Obviously, ammonium nitrogen is absorbed to a lesser extent by M. giganteus plants, compared to nitrate. The increase in ammonium content can be additionally caused by the activity of soil microbes in the rhizosphere of plants, which contributes to the accumulation of ammonium nitrogen in the soil. It has been shown that miscanthus plants actively absorbed water-soluble forms of phosphorus, especially in the period from June to September. The application of biochar was a significant source of phosphorus, although its release into the soil is a rather slow process. It was determined that additional amounts of potassium were added to the soil with biochar, which was actively used by the M. giganteus culture. The minimum amounts of potassium in both series of studies were absorbed by plants of E groups, where the content of diesel fuel in the soil was the highest. The introduction of petroleum products had a minor effect on the value of exchangeable acidity. The addition of biochar contributed to the shift of the acid-base balance in the direction of alkalinity, but after the end of the miscanthus vegetation (September), a decrease in the pH of the saline extract of the soil was noted. It is shown that the most noticeable decrease in the concentration of diesel fuel in the soil was noted under the conditions of adding biochar and after growing miscanthus, which can be effectively used for the remediation of lands contaminated by oil products.

Formation of productivity of giant miscanthus (Miscanthus×giganteus) under symbiosis of its root system with fungi and bacteria

The relevance of the subject under study is to increase the yield of dry biomass of giant miscanthus plants by using fungi and bacteria in its cultivation technology. The purpose of this study was to determine the effect of mycorrhization of the root system of this crop by fungi and symbiosis with bacteria on the growth and development of plants and the formation of their productivity. Field studies were conducted at the Veselopodilska Experimental Breeding Station of the Institute of Bioenergy Crops and Sugar Beet of the National Academy of Agrarian Sciences of Ukraine (Poltava region) during 2017-2019 on saline and slightly saline black soil. The significance of the deviation between the experimental variants was determined by the P-level calculated according to the Student’s test. The use of symbiosis of fungi and bacteria with the root system of giant miscanthus contributed to positive results in improving plant growth, development and dry biomass yield. The use of biological products Mycofriend, Mikovital, and Florobacillin (fungi Glomus VS. and Trichoderma harzianum Rifa, Tuber melanosporum Vittad and bacteria Bacillus subtilis Cohn) significantly increased the area of the leaf apparatus (by 6.9-19.0%), the weight of the root system (by 4.1-16.3%), increased plant height (by 3.7-13.6%), and the number of stems (by 5.7-15.1%) compared to the control. At the same time, there was an improvement in the soil’s moisture-holding capacity by 10.3-23.7% and its structural and aggregate state – the proportion of clods 0.25-10.0 mm in size was 3.2-5.7% higher than in the control. The use of mycorrhizal fungi and nitrogen-fixing bacteria contributes to an increase in the yield of dry plant biomass by 1.82-6.11 t/ha compared to the control, which is of practical importance in increasing the raw materials for biofuel production

Prediction of Storage Conditions to Increase the Bioenergy Efficiency of Giant Miscanthus Pellets Produced through On-Site Integrated Pretreatment Machines

Fossil fuels are associated with problems such as resource depletion and pollution, necessitating the exploration of alternatives. Giant miscanthus (Miscanthus × giganteus Greef et Deu), a perennial that can be harvested yearly, requires a low production energy input. It has less ash content and high heat efficiency and has attracted attention as an energy source. An on-site processing equipment, powered via a tractor and equipped with a chipper and a two-stage compression roller, was developed that can harvest 1000 kg of giant miscanthus per hour and simultaneously produce compressed pellets eliminating unnecessary processes such as transportation and processing. With its use, 33–74.5 kWh/t of electrical energy can be saved by producing pellets. The changes in moisture content between the produced compressed pellets and two samples of the ground product were measured immediately before compression for 24 h at relative humidity ranging from 65% to 80%. The moisture content was 6% initially; it ranged from 6.71% to 7.81% in compressed pellets, depending on the conditions, and from 7.44% to 9.82% in the ground sample immediately before compression, indicating the effect of the physical form of the biomass and humidity in the environment. The possible storage period (while maintaining the moisture content at 8–10% for optimal biofuel efficiency based on the measured data) was predicted. The optimal relative humidity of the storage environment for maintaining biomass quality for more than 6 months was predicted to be ≤77% and ≤70% for the compressed pellet and ground sample, respectively. Moreover, at a relative humidity ≥77%, giant miscanthus biomass, immediately before compression, had >10% moisture content in 2 days, warranting caution in storage.

Перспективні енергетичні культури на осушуваних торфовищах Лісостепу та їх водоспоживання в умовах зміни клімату

Goal. To determine the productivity of energy plantations, to investigate the parameters of water consumption of the main bioenergy crops on the drained organogenic soils of the Forest Steppe of Ukraine in modern conditions of climate change. Methods. Experimental on the basis of lysimeter studies and comparative-analytical, carried out on experimental sites of reclamation systems, mathematical modeling and processing of experimental data. The results. It was found that the maximum water consumption characteristic of the tristem willow in August is 8.02 thousand m3/ha, and this fact confirms the significant drying effect of tree crops. The lowest water consumption during the period of active vegetation was recorded in giant miscanthus — 2.53 thousand m3/ha. The total water consumption of Jerusalem artichoke from May to October was 18,100 m3/ha, corn — 12, sorghum — 10,800 m3/ha. It was found that lowering the groundwater level from 80 to 100 cm had little effect on the water consumption of Jerusalem artichoke, willow and miscanthus. The difference for these cultures does not exceed 1–3%. However, corn water consumption decreased by 112 L/kg dry matter, or 17%, and sorghum water consumption decreased by 205 L/kg, or 30% overall. In case of creation of large-scale bioenergy plantations, the area of which is measured in hundreds of hectares, it is necessary to modernize and repair the drying and humidification system. Conclusions. Climatic changes had a positive effect on the productivity of corn and sweet sorghum, the yield of dry biomass of which increased by 0.8 and 3.4 t/ha on average over three years, respectively, and negatively on the productivity of willow, it fell by 1.4 t/ha ; the productivity of miscanthus and Jerusalem artichoke did not change significantly. Therefore, when growing large plantations of energy crops, it is necessary to take into account the water regime of the land used: in fields with limited water resources, grow such annual crops as sorghum and corn, on lands with sufficient moisture — miscanthus, Jerusalem artichoke, in overmoistened places — willow plantations.

Energy and Biomass Yield of Industrial Hemp (Cannabis sativa L.) as Influenced by Seeding Rate and Harvest Time in Polish Agro-Climatic Conditions

ABSTRACT Energy produced directly from biomass represents an important part of available alternative energy sources. Industrial hemp has potential energy yields that are higher than those of many other energy crops and, as an annual herbaceous crop, hemp fits into existing crop rotations. The total biomass of hemp per hectare is similar to other energy crops, including mostly grown giant miscanthus, poplar, or willow. Industrial hemp is characterized by a short growing cycle, a decreased need for pesticides, and low plant maintenance. The energetic value of hemp depending on agrotechnical factors, such as sowing density and time of harvest, has been assessed in this study. A three-year field experiment was carried out to prove the possibility of using whole plants and separately hemp straw and panicles for energy purposes. C. sativa was sown at eight sowing rates − 5, 10, 15, 20, 30, 40, 50, and 60 kg · ha−1 and harvested at three developmental stages: at the beginning of panicle formation, at full flowering and at the end of seed setting. The optimal harvest time of hemp grown for energetic purposes was demonstrated to be at full flowering and the optimal sowing rate at 30 kg · ha−1 when hemp yielded 14.65 t · ha−1 equals 275.56 GJ · ha−1.

The Mobilization of Energy Crop Resources in Moldova

In the context of the current sharp rise in energy prices and frequent weather anomalies caused by climate change, humankind faces two major problems: food supply and energy security, which compels us to look for alternative ways of solving these problems, including the reduction of the dependence on fossil fuels and the development of new technological processes for renewable energy production. The main objectives of this study were to evaluate some agrobiological peculiarities and the quality of harvested biomass from local cultivars: ‘Solar’ Helianthus tuberosus, ‘Ileana’ Inula helenium, ‘Vital’ Silphium perfoliatum, ‘Energo’ Sida hermaphrodita, ‘Vigor’ Astragalus galegiformis, ‘Titan’ Miscanthus giganteus, ‘Argentina’ Sorghum almum, ‘Gigant’ Polygonum sachalinense and the prospects of using their biomass as feedstock for renewable energy production. It was found that the studied cultivars, in the second and following growing seasons, were characterised by optimal growth rate and moderate regenerative capacity after being mowed, making it possible to cut by 1-3 times per season, obtaining 4.61-14.25 kg/m2 green mass, which may be used for anaerobic digestion in biogas plants, with biochemical methane potential of 297-336 litre/kg organic matter. Besides, digestate and fugate are believed to be good fertilizers, being rich in plant available nutrients such as nitrogen, phosphate and potash, and could serve as a replacement for fossil based mineral fertilizers in organic farming. The stems of the studied cultivars quickly dehydrate in the autumn-winter period, and can be chopped, milled and used as feedstock for the production by cellulosic ethanol and solid bio fuel. The analysis of lignocellulose composition showed that the dry matter contained 375-517 g/kg cellulose, 211-305 g/kg hemicellulose, 68-134 g/kg acid detergent lignin. The estimated theoretical ethanol yield from cell wall carbohydrates averaged 408-591 L/t. The gross calorific value of stem biomass was 18.63-19.50 MJ/kg. The specific density of densified solid fuel pellets and briquettes meet the quality standard requirements. The obtained results indicate the possibility of using the local cultivars for the creation of energy plantations in the Republic of Moldova. The cultivation and harvesting of these cultivars do not require sophisticated mechanisms and specific equipment like as in forest exploitations.

Development of technology for accelerated propagation of miscanthus (Miscanthus giganteus)

Materials on the study of the low propagation coefficient of Miscanthus giganteus, the search for new ways of propagation and the development of technologies for accelerated propagation of this crop are presented. Artificial lighting and conditions of elevated temperature and humidity have shown a negative impact on the growth and development of Miscanthus gigantus plants in laboratory conditions. Artificial lighting stimulated the stretching of plants, which led to their lodging. Conditions of high temperature and humidity contributed to the development and rapid spread of brown rust disease.

Problems of production of Miscanthus Giganteus planting material

Purpose. Justification of directions for improvement of technology and means of production of miscanthus giant planting material through in-depth analysis of theoretical and experimental domestic and international research. Method. Analytical studies of the production processes of miscanthus giant planting material. Comparison of theoretical and experimental data of the analysis of existing information, many years of production and scientific experience of cultivation, collection and preparation of planting material using modern technical means. Results. Technologies for the production of planting material in Ukraine and the leading countries of the world are shown. The promising elements of the production technology of miscanthus giant planting material are substantiated. Conclusion. The priority direction of the development of the production of miscanthus giant planting material can be based on the improved elements of the technology of the comb method of planting rhizomes and the justification of the technical means for their implementation. The improvement of technological processes requires new research, which will be related to the study of planting density in combination with uprooting of plants in a row, establishing optimal terms for harvesting biomass and digging up rhizomes, further processing of biomass with increased humidity and storage of rhizomes in field conditions (in piles).

Patterns of changes in biometric indicators and productivity of giant miscanthus under the effect of mineral fertilization and foliar application of fertilizers in the Right Bank Forest-Steppe

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Growth and development of giant miscanthus under the effect of cultivation technology in the Right Bank Forest Steppe of Ukraine

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The concentration of heavy metals in the energy crops phytomass when grown in the conditions of Zhytomyr Polissia

The high level of anthropogenic pressure on agro-landscapes recently leads to an increased level of their contamination with heavy metals, which are among the most harmful chemical pollutants for the environment. Heavy metals are transmitted through trophic chains with a pronounced cumulative effect, in connection with which their toxicity can appear suddenly on individual links of trophic chains. The danger from heavy metals is determined by the fact that, unlike organic pollutants, they do not break down, but change from one form to another. Based on the results of the study, it was established that the accumulation of heavy metals by energy plants depended on the type of crop. Thus, it was proved that the concentration of heavy metals in energy crops plants when grown in the territory of radioactive contamination was within the limit of permissible concentrations. The lowest concentration of toxicants was noted when all energy crops were grown without fertilizers. The subject of the study was energy crops (Silhium perfoliatum L., Sorghum almum Parodi, Bunias orientalis L., Sida hermaphrodita Rusby, Miscanthus giganteus G.), heavy metals in plants, sod-podzolic sandy soil, mineral fertilizers. Therefore, the purpose of our research was to determine the phytomass of energy crops grown in areas contaminated with radionuclides as a result of the accident at the Chernobyl Nuclear Power Plant to determine the concentration of toxic substances. When performing the work, both general and special research methods were used: field – for conducting stationary and short-term field experiments, analytical – for determining the content of heavy metals in plants crops (Silhium perfoliatum L., Sorghum almum Parodi, Bunias orientalis L., Sida hermaphrodita Rusby, Miscanthus giganteus G.). The research was conducted during 2017−2020 on sod-podzolic soils in the territory of the village. Khrystynivka, Zhytomyr region, which belongs to the zone of unconditional (mandatory) resettlement (2nd zone of radioactive contamination). Prospects for further research will be aimed at establishing patterns of distribution of heavy metals in soil layers when growing energy crops. Key words: Silhium perfoliatum L., Sorghum almum Parodi, Bunias orientalis L., Sida hermaphrodita Rusby, Miscanthus giganteus G., lead, cadmium, copper, zinc.

The effect of nitrogen fertilization and foliar application of fertilizers on yield and energy efficiency of giant miscanthus plantations

Purpose. To improve the technology of caring for giant miscanthus plantations and establish the features of its productivity formation with the use of different types of fertilizers, starting from the second year of crop vegetation.
 Methods. The research was carried out in the years 2020–2021 in the Bila Tserkva Experimental and Breeding Station of the Institute of Bioenergy Crops and Sugar Beet of the National Academy of Agrarian Sciences of Ukraine, which is located in the zone of unstable moisture of the Right Bank Forest Steppe of Ukraine. The design of the experiment included application of mineral fertilizers [ammonium nitrate + ammonium sulfate (N24 + S6 kg/ha a.i.), ammonium nitrate (N24 kg/ha a.i.)] in a row zone in spring, foliar application of humates (Vermisol, 8.0 l/ha, Humifield BP-18, 0.4 l/ha) and complex fertilizer with amino acids (Quantum Aminomax, 0.5 l/ha). Mineral fertilizers were applied before the emergence of miscanthus sprouts; foliar application of fertilizers was carried out in the 5-leaf stage and the second time after two weeks.
 Results. Giant miscanthus plants in second year of vegetation formed from 18 to 37 shoots with an average weight of 76.3 to 111.0 g, with the maximum weight of one plant reaching 4091 g. In the next year of research, the number of stems per plant and their average weight increased by 1.5–2 times, and the maximum weight of one plant was 7016 g. Biomass yield of giant miscanthus in the third year of vegetation was 31.0–74.6 t/ha, the estimated yield of solid biofuel was 19.2–41.6 t/ha and energy 315.5–683.2 GJ/ha.
 Conclusions. Application of mineral fertilizers (ammonium nitrate + ammonium sulfate, ammonium nitrate) in spring contributed to significant increase in the indicators of raw biomass yield, solid biofuel output, and energy yield per hectare. Foliar application of Humifield BP-18 has a significant positive effect on the productivity of giant miscanthus. The best indicators of crop productivity were obtained in treatments combining spring fertilization with ammonium nitrate and ammonium sulfate (N24 + S6) followed by two-time foliar application of humates (Vermisol, 8.0 l/ha, Humifield BP-18, 0.4 l/ha) and complex fertilizer with amino acids Quantum Aminomax, 0.5 l/ha.