Korean J. Soil Sci. Fert. Vol.51, No.4, pp.547-554, 2018 Korean Journal of Soil Science and Fertilizer Article https://doi.org/10.7745/kjssf.2018.51.4.547 pissn : 0367-6315 eissn : 2288-2162 Effect of Application Levels of Inorganic Fertilizer with Biochar on Corn Growth in an Upland Field Se-Won Kang, Won-Jun Lee 1, Hong-Guk Jeong 1, Jae-Hyuk Park 1, Ju-Hee Lee 1, Jin-Ju Yun 1, Sang Yoon Kim 1, Dong-Cheol Seo 2, and Ju-Sik Cho 1 * Red River Research Station, Louisiana State University Agricultural Center, Bossier City, LA 71112, United States 1 Department of Bio-Environmental Sciences, Sunchon National University, Suncheon 57922, Korea 2 Division of Applied Life Science, Gyeongsang National University, Jinju 52828, Korea *Corresponding author: chojs@scnu.ac.kr A B S T R A C T Received: October 4, 2018 Revised: November 30, 2018 Accepted: November 30, 2018 This study was conducted to evaluate the effect of application levels of inorganic fertilizer (IF) with corn waste biochar (BC) for corn cultivation in an upland field (34 94ʹ 24ʺ N, 127 56ʹ 55ʺ E). The IF (N-P-K 14.5-3.0-6.0 kg 10a -1 ) was applied at levels of 25%, 50%, 75%, and 100% of standard amount with BC (BC+IF25, BC+IF50, BC+IF75, and BC+IF100, respectively), and Cn (control), BC and IF treatments were added in this study. The BC was application of 500 kg 10a -1 at 20 days before corn sowing. The mean biomass productivity of corn plants, when grown under Cn, BC, IF, BC+IF25, BC+IF50, BC+75, and BC+IF100 treatment conditions, were 1.82, 2.21, 2.74, 2.40, 3.12, 3.73, and 4.05 kg m -2, respectively. The corn length was 14.6-18.3 cm ear -1 in all treatments, and the total weight of corn increased in the order BC+IF100 BC+IF75 > BC+IF50 > IF > BC BC+IF25 > Cn treatments. The corn productivity was highest (3.97 kg m -2 ) in the BC+IF100 treatment. The corn grain yields in BC+IF50, BC+IF75, and BC+IF100 treatments increased by 145, 129, and 103% respectively, over that in the IF treatment. Based on our results, the minimum IF application level using biochar for corn cultivation was N of 7.25 kg 10a -1, P of 1.5 kg 10a -1, and K of 3.0 kg 10a -1, respectively. Therefore, proper application of inorganic fertilizer with biochar is effective at improving corn cultivation and can benefit the soil environment. Keywords: Application levels, Inorganic fertilizer, Corn waste biochar, Corn cultivation, Soil environment 160 140 Biomass productivity 160 140 Corn yield Grain yield 120 120 Index (%) 100 80 60 Index (%) 100 80 60 40 40 20 20 0 Cn BC IF BC+IF25 BC+IF50 BC+IF75 BC+IF100 0 Cn BC IF BC+IF25 BC+IF50 BC+IF75 BC+IF100 Treatments Treatments Comparison of biomass productivity and yields under different application levels of inorganic fertilizer with biochar. C The Korean Society of Soil Science and Fertilizer. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non- Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
548 Korean Journal of Soil Science and Fertilizer Vol. 51, No. 4, 2018 Introduction 무기질비료는작물의수량을증대시키고안정적인먹을거리확보를위하여기여해온중요한물질로편리성과식물이쉽게이용할수있는효율성을가지고있지만, 장기적또는과다시비될경우토양구조를악화시키는단점을가지고있다 (Kang et al., 2017). 이로인해최근환경부하를최소화한친환경농업이증가하고유기질비료, 녹비작물, 가축분뇨액비등의지원사업이지속적으로추진되어왔다 (Ok et al., 2016). 하지만, 국내농가에서는작물의안정적인생산량을유지하기위해무기질비료가꾸준히사용되고있으며, 그결과무기질비료의사용량은 2010년 233 kg ha -1 에서 2016년 268 kg ha -1 으로무기질비료의사용량이증가되고있는추세이다. 현재우리나라의 ha당무기질비료의사용량은 OECD 주요국가와비교하여높은수준으로분류되고있어장기적으로볼때토양환경을위한무기질비료의시비관리가필요한실정이다 (Kang et al., 2017). Biochar는혐기조건에서바이오매스를열분해시킨후얻어지는물질로, 진정한탄소네거티브방법은식물을 biochar로만들어토양에넣는방법을제안하면서많은관심을갖기시작한물질이다 (Lehman, 2007; Major, 2010). 이로인해 biochar는탄소격리를비롯해기후변화대응, 에너지생산, 토양개량및폐기물관리등다양한측면에서효과가있다고보고되었다 (Yamato et al., 2006; Case et al., 2012; Angst et al., 2014). Biochar는작물의생육을증진시킬수있는영양성분이무기질비료, 녹비작물, 가축분뇨액비등과비교하였을때상대적으로부족하지만, biochar의토양시용은토양구조를변화시키고토양내공기및양수분의흐름을원활하게하여작물의생육에도움을줄수있다고여러연구자들에의해보고되었다 (Kang et al., 2016). 특히, biochar는토양의 ph와 CEC를증가시켜작물의양분이용효율을증가시키는특성을가지고있기때문에적절한수준의무기질비료를 biochar와함께토양에투입한다면작물의수량과토양의비옥도를지속적으로유지시킬수있는관리방안이될것으로판단된다. 이에본연구에서는옥수수재배지에서 biochar를이용하여무기질비료의시용수준에따른옥수수의생산량을평가한후적절한무기질비료의시용수준을선정하여향후무기질비료의시비량을감축하고자하였다. Materials and Methods 공시재료 Biochar를이용한무기질비료 (N, 요소 ; P, 용과린 ; K, 염화가리 ) 의시용수준이옥수수의생육에미치는영향을평가하기위한시험지역은 Fig. 1에서보는바와같다. Fig. 1. Corn cultivation area in this study.
Effect of Application Levels of Inorganic Fertilizer with Biochar on Corn Growth in an Upland Field 549 선정된시험지역은전라남도광양시광양읍세풍리에위치한옥수수-배추윤작재배지로써배추수확후에옥수수를재배하였다. 시험지역은미사질양토의특성을가지고있었고, 재배시험전토양의용적밀도와공극률은각각 1.42 Mg m -3 및 46.4% 로용적밀도가일반밭에비해높은편이었다. 공시토양의화학적특성은 Table 1에서보는바와같이토양의 ph 및 OM 함량은각각 6.97 및 24.5 g kg -1 으로조사되었다. 공시작물은 N, P 및 K의투입에따라서긍정적으로반응하는하는옥수수를선정하였고 (Agegnehu et al., 2016), 옥수수종자는당도가높고재배지역이광범위한고당옥을선정하여사용하였다. 본시험에사용된 biochar는전남순천시서면에위치한순천대학교부속농장에서옥수수수확후남은부산물을사용하였다. Biochar 제조는드럼형제조장치를사용하였고, 혐기성조건을유지하면서 1시간동안열분해하였고, 제조된 biochar의화학적특성은 Table 2에서보는바와같다. Table 1. Chemical properties of experimental soil used in the study. ph EC OM T-N Avail. P 2 O 5 Exch. cations (cmol c kg -1 ) (1:5) (ds m -1 ) (g kg -1 ) (mg kg -1 ) K Ca Mg CEC 6.97 0.43 24.5 1.07 82.8 0.24 6.53 0.82 8.14 Table 2. Characteristics of corn waste biochar used in this study. ph EC T-N T-P K (1:10) (ds m -1 ) ----------------------------------------- (%) ----------------------------------------- 10.3 8.46 0.27 1.84 4.71 실험방법본시험을수행하기위한처리조건은 Table 3에서보는바와같다. 처리조건은 control (Cn), inorganic fertilizer (IF), corn waste biochar (BC), 그리고무기질비료의기준시비량대비 25% (BC+IF25), 50% (BC+IF50), 75% (BC+IF75) 및 100% (BC+IF100) 으로각각나누었다. BC의혼입시기와혼입량은 Kang et al. (2017) 의연구결과에준하여혼입시기는옥수수파종 20일전, 혼입량은 500 kg 10a -1 으로실시하였다. 무기질비료의시비량은농촌진흥청작물별시비처방기준에준하였다. 옥수수는 2018년 4월 6일에파종하였고, 7월 6일에옥수수를수확하였다. 옥수수식물체의생육특성은지상부길이, 생체중및단위면적 (m 2 ) 당바이오매스생산량을조사하였고, 수확한옥수수는길이, 옥수수와껍질그리고낱알의무게를조사한후단위면적 (m 2 ) 당수확량을산정하였다. Table 3. Treatment condition of this experiment. Treatment N-P-K Biochar ------------------------------------------------ (kg 10a -1 ) ------------------------------------------------ Cn - - IF 14.5-3.00-6.00 - BC - 500 BC+IF25 3.63-0.75-1.50 500 BC+IF50 7.25-1.50-3.00 500 BC+IF75 10.9-2.25-4.50 500 BC+IF100 14.5-3.00-6.00 500
550 Korean Journal of Soil Science and Fertilizer Vol. 51, No. 4, 2018 분석방법본시험에사용된토양및식물체의화학적특성은농촌진흥청의토양및식물체분석법 (NIAST, 2000) 에준하여분석하였다. 토양및 biochar의 ph 및 EC는 ph meter 및 EC meter (S230 Mettler Toledo) 를사용하였으며, 토양내유기물분석은 Tyurin법으로하였다. T-N 분석은 Kjeldahl법 ( 질소자동분석기, Gerhardt autosampler Vapodest 50 carouse, Germany) 을사용하였고, 유효인산분석은 Lancaster법 (UV2550PC, Pekinelmer) 을사용하였으며, 치환성양이온은 1N-NH 4 OAc 용액으로침출한후 ICP (ICPE-9000, Shimadzu) 를사용하여분석하였다. Biochar는습식분해법 (H 2 SO 4 + HClO 4 ) 으로전처리하여 T-N은 Kjeldahl법 ( 질소자동분석기, Gerhardt autosampler Vapodest 50 carouse, Germany) 으로분석하였고, T-P는 Vanadate법 (UV2550PC, Pekinelmer) 으로분석하였으며, K는 ICP (ICPE-9000, Shimadzu) 를사용하여분석하였다. 무기질비료의시용수준에따른옥수수의생육결과에대한통계분석은 SPSS 25 버전을사용하여 5% 유의수준에서 Duncan s multiple range test를수행하였다. Results and Discussion 옥수수의생육특성옥수수식물체의생육특성을조사한결과는 Table 4에서보는바와같다. 식물체의지상부길이는 Cn 처리구에서 148 cm plant -1, BC 처리구에서 154 cm plant -1 이었고, 무기질비료가시비된처리구에서는 164-171 cm plant -1 범위로큰차이없이비슷하였다. 옥수수수확후발생된식물체의생체중은처리조건에따라차이가났으며, 특히 BC+IF100 처리구가다른처리구에비해생체중이많았다. 옥수수식물체의생체중결과를이용하여단위면적 (m 2 ) 당바이오매스생산량으로환산한결과 BC+IF100 처리구가 4.05 kg m -2 으로가장많은생산을보였고, Cn 처리구가 1.82 kg m -2 으로가장적은생산을보였다. 한편, BC와수준별 IF 혼합처리구인 BC+IF25, BC+IF50, BC+IF75 및 BC+IF100 처리구에서생산된바이오매스생산량은 IF 처리구대비각각 87.5, 114, 136, 그리고 148% 의결과를보였다 (Fig. 2). Table 4. Growth characteristics of plant after corn harvest. Treatment Plant height Fresh weight Biomass productivity (cm plant -1 ) (g plant -1 ) -------------------- (kg m -2 ) -------------------- Cn 148a 152a 1.82a BC 154b 184b 2.21b IF 170d 228c 2.74c BC+IF25 164c 200b 2.40b BC+IF50 167bc 260d 3.12d BC+IF75 166bc 311e 3.73e BC+IF100 171d 338f 4.05f Means by the same within a column are not significantly different at 0.05 probability level according to Duncan s Multiple Range Test. 옥수수수확후처리구별생육을비교한결과는 Table 5와같다. 옥수수의단위면적 (m 2 ) 당생산량은 BC+IF75 및 BC+IF100 처리구에서각각 3.56 및 3.97 kg m -2 으로 IF 처리구 (2.81 kg m -2 ) 에비해약 127 및 142% 증가된수준으
Effect of Application Levels of Inorganic Fertilizer with Biochar on Corn Growth in an Upland Field 551 160 140 Biomass productivity 120 Index (%) 100 80 60 40 20 0 Cn BC IF BC+IF25 BC+IF50 BC+IF75 BC+IF100 Treatments Fig. 2. Comparison of biomass productivity after corn harvest. Table 5. Growth characteristics of corn after corn harvest. Treatment Total weight Corn yield Straw Grain yield Corn productivity Length ---------------------------- (g plant -1 ) ---------------------------- (kg m -2 ) (cm ea -1 ) Cn 102a 78.3a 23.7a 45.8a 1.88a 14.8a BC 128b 85.5ab 42.7b 49.4a 2.05ab 15.1a IF 141c 117c 23.7a 87.9c 2.81c 16.3b BC+IF25 120b 87.8b 32.2a 62.4b 2.11b 14.6a BC+IF50 179d 126d 53.1c 90.2c 3.03d 17.4bc BC+IF75 212e 148e 63.8d 113d 3.56e 18.3c BC+IF100 213e 166f 47.8bc 128e 3.97f 17.7c Means by the same within a column are not significantly different at 0.05 probability level according to Duncan s Multiple Range Test. 로조사되었다. 이는 biochar 시용으로인해토양물리성이개선되면서옥수수생육에필요한양수분의공급이원활했던것으로판단된다 (Nigussie et al., 2012; Carter et al., 2013). Carvalho et al. (2016) 및 He et al. (2016) 은 biochar 와다른물질의혼합은토양의다각적인기능을향상시킬수있다고보고한바있기때문에본연구에서 biochar와무기질비료의혼합처리구가전반적으로높은수확량을나타낸것으로보인다. 또한, Major et al. (2010) 은 biochar가 Ca나 Mg 같은토양내에부족한토양영양분을공급하여옥수수의생육을개선할것을제안한바있다. 한편, BC 및 BC+IF25 처리구는 IF 처리구에비해옥수수의생산량이각각 27% 및 25% 감소되는결과를보여주었고, BC+IF50 처리구에서는 IF 처리구에비해약간증가된옥수수생산량을보여주었다. Biochar 시용후에작물생육은작물의종류, 기후, 그리고토양특성등에크게영향을받는다 (Gakin et al., 2010; Alburguerque et al., 2013; Karer et al., 2013). Rogovska et al. (2014) 는 biochar 시용이옥수수의수량과바이오매스생산량에긍정적인영향을미친다고보고한바있지만, Asai et al. (2009) 는 biochar의낮은무기성분특성과높은 C/N비로인해서식물생육에필요한양분이용을제한할수있기때문에작물의수확량이감소될수있다고보고한바있다. Biochar는원재료및열분해제조조건에따라서그특성이달라지기때문에본연구에서는다른양분의도움없이 biochar 자체만으로는작물의높은생산성을기대하기에한계가있었던것으로사료된다. 따라서본연구에서 biochar를이용한옥수수재배에서는무기질비료를기준시비량대비최소한 50% 이상을시비하여야안정적인옥수수생산량을유지할수있었다 (Fig. 3).
552 Korean Journal of Soil Science and Fertilizer Vol. 51, No. 4, 2018 160 140 Corn yield Grain yield 120 Index (%) 100 80 60 40 20 0 Cn BC IF BC+IF25 BC+IF50 BC+IF75 BC+IF100 Treatments Fig. 3. Comparison of corn and grain yields after corn harvest. 토양특성변화옥수수수확후토양의화학적특성을조사한결과는 Table 6에서보는바와같다. 처리구별토양 ph는 Cn 처리구에서 6.78, IF 처리구에서 6.77로옥수수재배전토양의 ph에비해감소하였고, biochar가혼입된처리구는 7.01-7.48 범위로 ph가증가하였다. 토양내 OM, T-N 및 CEC는 ph의경향과유사하게 biochar가혼입된처리구에서유의성있게증가되었다 (Pandey et al., 2016). 바이오매스가열분해되면유기매트릭스로부터알칼리염이분리되면서생성물질의 ph를증가시킨다. 이로인해열분해로부터생성된옥수수부산물 biochar는높은 ph를가지게되었고, 토양에혼입되어 ph를증가시켰던것으로판단된다 (Peng et al., 2011; Kamara et al., 2015). 또한, biochar는높은표면적과전하밀도를가지고있어 biochar를혼입한처리구내토양의 CEC를증가시킨것으로보인다 (Liu et al., 2016). Table 6. Changes in soil chemical properties after corn harvest. Treatment ph EC OM T-N Avail. P 2 O 5 CEC (1:5) (ds m -1 ) ----------- (g kg -1 ) ----------- (mg kg -1 ) (cmol c kg -1 ) Cn 6.79a 0.29a 22.2a 0.87a 80.9d 7.96a BC 7.48e 0.31b 25.3b 1.02bc 74.8b 8.26ab IF 6.77a 0.29a 21.3a 0.99b 68.6a 8.04a BC+IF25 7.27d 0.33c 26.2b 1.14d 70.7a 8.21b BC+IF50 7.02b 0.34d 25.6b 1.11d 77.4c 8.33b BC+IF75 7.13c 0.37e 25.8b 1.15d 85.6e 8.45b BC+IF100 7.01b 0.34cd 25.5b 1.08cd 80.8d 8.38b Means by the same within a column are not significantly different at 0.05 probability level according to Duncan s Multiple Range Test. Conclusions 본연구는 biochar와무기질비료의수준별시용이옥수수의생육에미치는영향을평가하여무기질비료의시비량을절감하기위한방안을제시하고자하였다. 무기질비료의수준별시용량은기준시비량의 25%, 50%, 75% 및
Effect of Application Levels of Inorganic Fertilizer with Biochar on Corn Growth in an Upland Field 553 100% 를 biochar와혼입하여옥수수재배시험을진행하였다. 무기질비료의시용수준에따른옥수수의생육은전반적으로 BC+IF50, BC+IF75 및 BC+IF100 처리구에서식물체의길이, 바이오매스및옥수수의생산량등이기준처리구인 IF 처리구에비해증가되는결과를나타내었고, 무기질비료시용수준이높을수록옥수수의생육이증가되는유의성을보여주었다. 하지만, BC+IF25 처리구에서조사된옥수수의생산량및생육지표가 IF 처리구에비해감소되는결과를보였다. 옥수수수확후조사된토양의화학적특성은무기질비료의수준별시용에상관없이 biochar 시용유무에따른결과를보여주었으며, biochar를시용한처리구가작물의생장과관련이깊은 ph, OM 및 CEC 등의항목에서유의성있게증가되는결과를보였다. 따라서본시험의결과로미루어볼때 biochar와무기질비료의혼입은옥수수의생산량을증가시킬수있을것으로보이며, 농가에서 biochar를이용한옥수수재배에서는 BC+IF50 조건이옥수수의안정적인생산량을유지하고토양건전성을유지하는데적당하다고판단된다. Acknowledgement This work was carried out with the support of Cooperative Research Program for Agriculture Science & Technology Development (Project No. PJ011227042018) Rural Development Administration, Republic of Korea. References Agegnehu, G., A.M. Bass, P.N. Nelson, and M.I. Bird. 2016. Benefits of biochar, compost and biochar compost for soil quality, maize yield and greenhouse gas emissions in a tropical agricultural soil. Sci. Total Environ. 543:295-306. Alburquerque, J.A., P. Salazar, V. Barrόn, J. Torrent, M.C. del Campillo, A. Gallardo, and R. Villar. 2013. Enhanced wheat yield by biochar addition under different mineral fertilization levels. Agron. Sustain. Dev. 33:475-484. Angst, T.E., J. Six, D.S. Reay, and S.P. Sohi. 2014. Impact of pine chip biochar on trace greenhouse gas emissions and soil nutrient dynamics in an annual ryegrass system in California. Agric. Ecosys. Environ. 191:17-26. Asai, H., B.K. Samson, H.M. Stephan, K. Songyikhangsuthor, K. Homma, Y. Kiyono, Y. Inoue, T. Shiraiwa, and T. Horie. 2009. Biochar amendment techniques for upland rice production in Northern Laos 1. Soil physical properties, leaf SPAD and grain yield. Field Crops Res. 111:81-84. Carter, S., S. Shackley, S. Sohi, T.B. Suy, S. Haefele. 2013. The impact of biochar application on soil properties and plant growth of pot grown lettuce (Lactuca sativa) and cabbage (Brassica chinensis). Agronomy. 3:404-418. Carvalho, M.T.M., B.E. Madari, L. Bastiaans, P.A.J. van Oort, W.G.O. Leal, A.B. Heinemann, M.A.S. da Silva, A.H.N. Maia, D. Parsons, and H. Meinke. 2016. Properties of a clay soil from 1.5 to 3.5 years after biochar application and the impact on rice yield. Geoderma. 276:7-18. Case, S.D.C., N.P. McNamara, D.S. Reay, and J. Whitaker. 2012. The effect of biochar addition on N 2 O and CO 2 emissions from a sandy loam soil - The role of soil aeration. Soil Biol. Biochem. 51:125-134. Gaskin, J.W., R.A. Speir, K. Harris, K.C. Das, R.D. Lee, L.A. Morris, and D.S. Fisher. 2010. Effect of peanut hull and pine chip biochar on soil nutrients, corn nutrient status, and yield. Agron. J. 102:623-633. He, L., X. Zhao, S. Wang, and G. Xing. 2016. The effects of rice-straw biochar addition on nitrification activity and nitrous oxide emissions in two Oxisols. Soil Tillage Res. 164:52-62. Kamara, A., H.S. Kamara, and M.S. Kamara. 2015. Effect of rice straw biochar on soil quality and the early growth and biomass yield of two rice varieties. Agric. Sci. 6:798-806.
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