ISSN 1392-3196 Zemdirbyste-Agriculture Vol. 106, No. 4 (2019) 297 ISSN 1392-3196 / e-ISSN 2335-8947 Zemdirbyste-Agriculture, vol. 106, No. 4 (2019), p. 297–306 DOI 10.13080/z-a.2019.106.038 Efect of biochar on N 2 O emission, crop yield and properties of Stagnic Luvisol in a feld experiment Elena Y. RIZHIYA 1 , Irina M. MUKHINA 1 , Eugene V. BALASHOV 1 , Vladimír ŠIMANSKY 2 , Natalya P. BUCHKINA 1 1 Agrophysical Research Institute Grazhdansky 14, 195220 St. Petersburg, Russia E-mail: buchkina_natalya@mail.ru 2 Slovak University of Agriculture, Faculty of Agrobiology and Food Resources Tr. A. Hlinku 2, 949 76 Nitra, Slovakia Abstract Soils are one of the main sources of nitrous oxide (N 2 O) in agriculture. Soil management practices can signifcantly afect N 2 O emissions through changing soil physical, chemical and biochemical properties. Application of biochar to arable soils can be an option for N 2 O emission mitigation, but the efect of biochar can be diferent for soils with diferent fertility levels. The objective of this study was to evaluate the efect of biochar application on N 2 O emission, soil properties and barley yield from loamy sand Stagnic Luvisol with high and medium levels of fertility caused by high rates of farmyard manure and fertilizer application for 10 years. A small-scale feld experiment was conducted during the growing season of 2012 in North-Western Russia. Four treatments were used in the experiment: 1) control (no biochar, no N-fertilizer), 2) biochar (12 t ha -1 ), 3) N-fertilizer (90 kg ha -1 N) and 4) biochar (12 t ha -1 ) + N-fertilizer (90 kg ha -1 N), in fve replicates. Signifcant changes in water-holding capacity and the amount of available nitrogen (N) occurred in the soil with high fertility, and thus it emitted signifcantly more N 2 O for the growing season than the soil with medium fertility. Biochar application efect on N 2 O emissions depended on the soil management history and was reducing the emission from the soil with high fertility rich in mineral N and C but not from the soil with medium fertility if no nitrogen fertilizer was applied to the latter soil. The yield-scaled N 2 O emission was the highest from the control treatments for the soil with both fertility levels, and the soil with high fertility was always characterized by higher yield-scaled N 2 O emissions than the soil with medium fertility. Application of biochar reduced yield-scaled N 2 O emission from the soil with medium and high fertility levels showing that biochar application to the soil can improve N use by the plants. Key words: biochar, N 2 O emissions, small-scale experiment, soil fertility, soil properties, yield-scaled emissions. Introduction It is well known that a regular application of farmyard or green manure to a light-textured soil contributes to higher soil fertility due to decreasing soil bulk density, increasing mineral nitrogen (N) and organic carbon (C) content, increasing soil porosity and water- holding capacity (Dabek-Szreniawska, Balashov, 2007; Ding et al., 2007; Buchkina et al., 2013). Apart from this positive efect, application of manures can cause increased nitrous oxide (N 2 O) fuxes (Broucek, 2017), supported by higher content of total organic C and plant- available N. One of the tools for an essential improvement of soil fertility and quality could be biochar application (Glaser et al., 2002; Horak et al., 2017). Biochar is manufactured through the pyrolysis of biomass feedstocks at temperatures of 300–800°C under complete exclusion of oxygen (Lehmann et al., 2003; Yanai et al., 2007; Van Zwieten et al., 2010 b). Biochar is a heterogenenous material which, due to its aromatic structure, is highly recalcitrant in soils with long-term residence time. Incorporation of biochar into arable soils can result in an improvement of their physical (porosity, aeration) and physico-chemical (pH, cation exchange capacity) properties, because porous, carbonaceous biochar with a high afnity to adsorption of water, cations (Ca, Zn and Mn) and organic substances demonstrates a high water- holding and cation exchange capacity (Saarnio et al., 2013; Tesfahun, 2018). In some experiments, a decrease in N 2 O emission from agricultural soils was often observed after application of biochar of diferent origin due to a lower mineral N availability and higher mineral N Please use the following format when citing the article: Rizhiya E. Y., Mukhina I. M., Balashov E. V., Šimansky V., Buchkina N. P. 2019. Efect of biochar on N 2 O emission, crop yield and properties of Stagnic Luvisol in a feld experiment. Zemdirbyste-Agriculture, 106 (4): 297–306. DOI 10.13080/z-a.2019.106.038