ISSN 2617-6106 (print) ISSN 2617-6114 (online) Agrology, 3(1), 3‒11 AGROLOGY doi: 10.32819/020001 Оriginal researches The Biochar Impact on Miscanthus and Sunflower Growth in Marginal Lands M. M. Kharytonov1, I. I. Klimkina2, N. V. Martynova3, I. V. Rula1, Received: 22 November 2019 M. Gispert4, G. Pardini4, J. Wang5 Revised: 02 December 2019 1Dnipro State Agrarian and Economic University, Dnipro, Ukraine Accepted: 03 December 2019 2Dnipro University of Technology, Dnipro, Ukraine 3Oles Honchar Dnipro National University, Dnipro, Ukraine Dnipro State Agrarian and Economic 4Girona University, Girona, Spain University, Serhii Efremov Str., 25, Dnipro, 5Lousiana State University, Baton Rouge, USA 49000, Ukraine Dnipro University of Technology, Dmytro Yavornytsky Av., 19, Dnipro, 49005, Ukraine Abstract. The results of the experiment with biochar as a soil amendment are presented. Two energy crops (Miscanthus × giganteus and Helianthus annuus) were grown in the vegetation Oles Gonchar Dnipro National University, containers with two types of marginal lands. Low humus black soil Low humus black was taken Gagarin Av., 72, Dnipro, 49000, Ukraine in flood plain of Kilchen river. Red-brown clay was taken from the quarry board 15 yeas ago to Girona University, Maria Aurelia Capmany, create reclaimed mine land in site near “Blagodatna” coal mining tailing. It was defined that the 61, Girona, 17003, Spain biochar addition intensifies growth processes from 7‒30% (Helianthus) to 20‒88 % (Miscanthus). For Miscanthus, the effect was more pronounced on black soil, and for Helianthus on red-brown Lousiana State University, 313 M. B. Sturgis, Baton Rouge, LA 70803, Baton Rouge, USA clay. Due to the biochar application, the plant capacity to take up heavy metals by above-ground organs decreased. As a result, the heavy metal content in leaves and stems has reduced by an av- Lousiana State University, 313 M. B. Sturgis, erage of 10‒25%. However, because of the gain in biomass productivity, the uptake level of some Baton Rouge, LA 70803, USA heavy metals has increased. Especially, this was characteristic of the Miscanthus leaf biomass. So, the uptake of heavy metals by leaves increased from 28.1% (Pb) to 62.9% (Fe) on the black soil, Tel.: +38-096-057-17-84 and from 20.3% (Cu) to 46.6% (Zn) on the red-brown clay. The addition of biochar had a slight E-mail: [email protected] effect on thermolysis passing of Miscanthus and Helianthus biomass. So, in Miscanthus, duration of the process has grown shorter. The rate of thermal degradation in the leaf biomass was greater, Cite this article: Kharytonov, M. M., which is especially noticeable in the region of hemicelluloses destruction. In the stem biomass a Klimkina, I. I., Martynova, N. V., Rula, I. V., pronounced increase in the thermolysis rate was noted in the region of volatile components evap- Gispert, M., Pardini, G., & Wang, J. (2020). oration (on the black soil) and during the cellulose decomposition. Besides, under the impact of The biochar impact on miscanthus and biochar, biomass combustion was more complete (by 5.1% on the red-brown clay and by 30% on sunflower growth in marginal lands. Agrology, 3(1), 3‒11. doi: 10.32819/020001 the black soil). In leaf biomass of Helianthus, the onset of thermolysis has shifted toward higher temperatures. In addition, the magnitude of the thermal effect was greater at almost all stages of decomposition. In stem biomass, thermal effects also increased, but only slightly. Under the influence of biochar, the first stage of decomposition was faster. In biomass taken from red-brown clay, the rate of hemicellulose degradation also increased. In biomass taken from black soil, bi- ochar application contributed to more intensive decomposition of lignin. After combustion, the share of residual mass in stem of plants grown on black soil with the biochar addition increased by 30%. The opposite effect was observed on red-brown clay: the share of residual mass decreased by 49%. Besides, the thermal stability of stem biomass grown on the substrates using biochar lessened by 8‒16%. Keywords: Miscanthus; Helianthus; post-mining soils; biochar; heavy metals; biomass thermal features. Introduction Soil degradation trends can be reversed by conversion to a re- storative land use and adoption of recommended management prac- Soil degradation processes, as a result of anthropogenic activ- tices. Improving soil quality can reduce risks of physical, chemical, ity, exceeding the natural soil formation rates, are urgent problems biological and ecological soil degradation. Techniques of restor- of our time. Among the major soil degradation processes are acce- ing soil quality include conservation agriculture, integrated nutri- lerated erosion, depletion of the soil organic carbon pool, loss of ent management, and continuous vegetative cover such as residue soil fertility and elemental imbalance, acidification and salinization mulch and cover cropping, and controlled grazing at appropriate (Jie, Jing-zhang, Man-zhi, & Zi-tong, 2002; Lal, 2015). In industri- stocking rates. The strategy is to produce “more from less” by re- ally developed regions, degradation occurs especially quickly, since ducing losses and increasing soil, water, and nutrient use efficiency during the cycles of mining and production a large amount of land (Labreuche, Lellahi, Malaval, & Germon, 2011; Lal, 2015). Sus- is formed, unsuitable for farming. The disadvantage of such soils is tainable intensification, producing more from less by reducing los- not only loss of fertility, but also pollution by heavy metals and oth- ses and increasing the use efficiency, is attainable through improve- er industrial wastes. A direct implication of the imbalance between ment of soil quality including chemical quality or soil fertility. Use agricultural soil loss and erosion is that, given time, continued soil of organic amendments, by recycling organic by-products is a useful loss will become a critical problem for global agricultural produc- strategy to enhance soil fertility and improve structural stability or tion (Pimentel, 2006; Montgomery, 2007; Gomiero, 2016). aggregates (Abbott & Murphy, 2007; Laird, 2007; Lal, 2015). Use AGROLOGY | Volume 3 | Issue 1 3 M. M. Kharytonov, I. I. Klimkina, N. V. Martynova, I. V. Rula, M. Gispert, G. Pardini, J. Wang The biochar impact on miscanthus and sunflower growth in marginal lands of biochar and biochar-compost mixtures from different alternative top of salinated stratum (0‒20 cm) in flood plain of Kilchen river organic sources can be proposed as an option for improving soil (Samara river tributary). Red brown clay was taken from quarry fertility, restoring degraded land, and mitigating the emissions of board 15 yeas ago to create reclaimed mine land in site near Blago- greenhouse gasses associated with agriculture. Biochar application datnaya coal mining tailing in Pavlogradsky district (Western Don- could be a feasible alternative to remediate the degraded soils and bass coal ming region). 40 cm stratum of brown clay was replaced improve their productivity potential in the long-term (Verheijen, Jef- over salinated and polluted with heavy metals stratum consisting of fery, Bastos, van der Velde, & Diafas 2009; Scislowska, Wlodarczyk, 4 m mass of mining rocks mix (Kharytonov & Kroik, 2011; Klim- Kobylecki, & Bis, 2015; Agegnehu, Srivastava, & Bird, 2017). kina, Kharytonov, & Zhukov, 2018). Biochar was applied to test its In the conventional sense, the term biochar means biomass that effect on plant growth, the ability of plants to accumulate of heavy has undergone pyrolysis in an oxygen-free environment. Owing to its metals and the thermal characteristics of biomass. Treatments in- immanent properties, the biochar is regarded as soil amendment for cluded control and nutshell biochar (3% by weight). sustained carbon sequestration and concurrent improvement of soil Germinating ability (for Helianthus) and growth parameters functions. In the presence of biochar in the soil mixture, its contribu- were studied by biometric methods. The content of heavy metals in tion to the physical nature of the system may be significant, influencing above-ground biomass was determined. For analysis, biomass sam- depth, texture, structure, porosity and consistency through changing ples weighing 2 g each were combusted in a muffle furnace at 450 °C the bulk surface area, pore-size distribution, particle-size distribution, by means of drying method and then dissolved in 5 ml of 6N spectral density and packing. Biochar’s effect on soil physical properties may purity hydrochloric acid. The content of mineral elements in obtained then have a direct impact upon plant growth because the penetration mineralizes was measured by atomic absorption spectrophotometric depth and availability of air and water within the root zone is deter- analysis at Varian Cary-50. The received data represented the arithme- mined largely by the physical make-up of soil horizons (Downie, tic means of three replicates of each sample, their ranges and standard Crosky, & Munroe, 2012; Hardie, Clothier, Bound, Oliver, & Close, deviations values. The thermal characteristics of biomass were stu- 2014; Chia, Downie, & Munroe, 2015). Each biochar made with a died by thermogravimetric analysis. The analysis was performed using particular feedstock and process combination presents a unique mix- the derivatograph Q-1500D of the “F. Paulik-J. Paulik-L. Erdey” sys- ture of phases and microenvironments that gives rise to a unique set of