Korean J. Soil Sci. Fert. Vol.51, No.4, pp.427-434, 2018 Korean Journal of Soil Science and Fertilizer Article https://doi.org/10.7745/kjssf.2018.51.4.427 pissn : 0367-6315 eissn : 2288-2162 Estimation of Nutrient Balance in Field Crops Applied with Different Fertilization Seok Cheol Kim, Myung Sook Kim, Seong Jin Park, Seong Heon Kim**, and Chang Hoon Lee* Soil and Fertilizer Division, National Institute of Agricultural Sciences, RDA, Wanju 55365, Korea *Corresponding author: chlee915@korea.kr **This author contributed equally to this works as corresponding authors. A B S T R A C T Received: August 24, 2018 Revised: October 28, 2018 Accepted: November 1, 2018 Korea is one of those countries that have very high usage rates of chemical fertilizers per unit area of cropland. To reduce the fertilizer application rate, a variety of agricultural polices has been introduced since the 1990s. The purpose of this study was conducted to find out the situation of fertilizer use on vegetable crops at 720 farmer s fields located in 9 province area. Organic fertilizer application rates increased in major field crops. Chemical fertilizer application rates decreased in most of the field crops and vegetables surveyed; however, this reduction was concentrated in phosphate and potassium usage but not in nitrogen. In spite of this decrease, the fertilizer application levels to most crops were maintained at levels much higher than recommended. In the nutrient balance, which was calculated from the difference between input (chemical and organic fertilizers) and output (agricultural products), the nitrogen surplus were higher than recommendation fertilizer application rate. To reduce fertilizer utilization and to conserve environment, further reduction of fertilizer application is essential. Keywords: Field crop, Fertilization, Inorganic fertilizer, Organic fertilizer, Nutrient balance Distribution of nutrient balance in upland soil with different fertilization. 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.
428 Korean Journal of Soil Science and Fertilizer Vol. 51, No. 4, 2018 Introduction 비료는식물에영양을주거나식물의재배를돕기위하여토양에시용하는물질을뜻하며 (RDA, 2017), 비료중화학비료는저렴한가격, 편리성및속효성양분공급등의장점으로오랫동안농경지에사용되고있다 (Lee et al., 2008). 그러나농경지에화학비료의과다사용은토양중양분의불균형을초래하고, 토양유기물을낮춘다 (Lee et al., 2012). 또한지속적인화학비료시용은토양질을퇴보시켜지속적인작물생산에영향을미치기도한다 (Nguyen et al., 1995). 1980년대이후고투입집약농업에서지속적농업으로전환하기위해양분종합관리 (integrated nutrient management, INM) 가도입되었고, 농경지의합리적시비관리로화학비료사용량을개선시켰다 (Parris, 2011). 예를들어, OECD 국가는화학비료에의한농경지양분손실을약 17% 줄었으나, 농경지로부터유출된질소와인이주변수계의수질에각각 30-80% 및 20-70% 기여하였다 (Parris, 2011). 그러므로농경지에화학비료의적정시비는수질보전등농업환경변동에상당한영향을미칠수있다. 농경지에비료사용량은변동되어왔다. 예들들어, 1997년친환경농업육성법이제정된이후무기질비료에대한정부보조금지원이감소된결과, 무기질비료의사용량은 2000년도 381.9 kg 10a -1 에서 2010년 232.7 kg 10a -1 로 29.1% 감소되었다 (Jeon et al., 2014). 그러나농경지에퇴비및유기질비료등의과다시용은염류집적 (Mer et al., 2000), 양분불균형 (Lee et al., 2009), 환원장애 (Ramollya and Pendey, 2002) 등이발생되고, 작물생산성감소 (Cho and Park, 2002) 와더불어유출양분에의한농업환경부하량증가에원인이되고있는실정이다 (Lee et al., 2010; Lee et al., 2011). 그러나농경지작물생산과농업환경에대한영향은농경지에사용되는비료량과밀접한관계를있으며, 이를평가하기위한경종농가의비료사용현황이필요하다. 비료사용실태조사는비료사용량을직접 간접방법을통하여실제농경지에시비된비료를조사하고, 이를통해작물생산과농업환경의변화양상을평가및비료사용의문제점을파악하는데있다 (RDA, 2017). 기존연구에따르면, 고랭지작물 (Lee et al., 2006) 및밀재배를위한시비 (Kim et al., 2016), 화학비료사용실태 (Gil, 2000) 등특정작물또는단일화학비료조사가주를이루고있었다. 따라서본연구는밭작물에대한비료사용실태를조사하고자하였다. 이를위한대표적인밭작물 7종을선정하여전국 700 개소의농가에서비료사용량, 비료종류, 생산성을자료를사용하였다. 이상의결과를이용하여밭작물비료사용에따른양분수지분포특성을평가하여농경지로부터유출되는양분의변동을평가하는기초자료를제공하고자하였다. Materials and Methods 조사대상조사지역및대상은각도별로재배면적이가장많은노지작물을선정하여경기 ( 고추 25개소, 및배추 25개소 ), 강원 ( 고랭지배추 50개소및무 25개소 ), 충북 ( 고추 25개소, 배추 25개소및마늘 50개소 ), 충남 ( 고추 20 개소, 마늘 2개소및파 20개소 ), 전북 ( 고추 20개소, 배추 20개소, 무 20개소및파 20개소 ), 전남 ( 배추 20개소, 마늘 20개소, 파 40개소및양파 20개소 ), 경북 ( 고추 20개소, 배추 20개소, 마늘 20개소및양파 20개소 ), 경남 ( 고추 20개소, 배추 20개소, 마늘 30개소및양파 30개소 ) 및제주 ( 무 20개소, 마늘 35개소및양파 20개소 ) 로 9개도에각각 720 농가를선정하였다.
Estimation of Nutrient Balance in Field Crops Applied with Different Fertilization 429 조사방법및내용조사방법은각도별농업기술원에서선정된농가에직접방문하여면접청취조사를원칙으로하였다. 조사내용은작물종류에따른비료투입량, 비료종류 ( 무기질비료, 유기질비료, 퇴비등 ) 에따른성분량, 비료사용방법및생산량을조사하였다. Data 분석조사한 data를활용하여국내밭작물의총비료투입량을도출하였으며, 무기질비료및부숙유기질비료의투입량과투입비율을도출하였다. 작물생산량은조사된고랭지배추 (n=31), 고추 (n-112), 대파 (n=58), 마늘 (n=153), 무 (n=28), 배추 (n=121) 및양파 (n=84) 의결과값을이용하였다. 작물종류에따른양분흡수량은 Kim et al. (2003) 의밭작물종류별양분량결과를참고하여사용하였으며, 작물생산량과양분량을이용해작물별양분흡수량을계산하였다. 그후작물종류에따른비료총투입량 (input) 에서양분흡수량 (output) 을차감하여이용해양분수지를산정하였다. 통계분석 모든데이터는 ANOVA 분석을실시하였고, 각구간에평균비교는유의수준 5% 로 Duncan 분석을하였다. Results and Discussion 비료투입현황 Fig. 1의경우현재시비되고있는총투입량을나타낸결과로 Fig. 1은국내실제비료의총투입량을나타낸결과로 N, P 2 O 5 및 K 2 O의투입량은각각최대 28.65, 20.78 및 22.82 kg 10a -1 이었으며평균 5.40±3.09, 3.50±2.54 및 3.61±2.92 kg 10a -1 로나타났다. 결과를통해 N, P 2 O 5 및 K 2 O의투입량이평균 1.29, 2.27 및 2.59 kg 10a -1 로과다시비되고있는것을확인하였으며이결과는평균값이지만실제더많이과다투입되고있는것으로확인되었다. Park et al. (1994) 에따르면 1960년후반부터시비효율이낮은우리나라의토양비옥도를높이기위해자급비료등의사용을권장하였으며, 통일벼와같은비료요구도가높은작물로인해과잉시비를권장하였다고보고하고있다. 이러한과잉시비의경우 1990년이후표준시비량하향조정 (RDA, 1993) 과벼를포함한밭작물및시설채소 24종에대한표준시비량설정또는새로운시비량설정 (RDA, 1998) 등개선을위해노력하고있으나과잉시비의습관때문에아직까지농가에서는과다투입을하고있다고알려져있다 (Choi et al., 2009). Fig. 1. Distributions of gross nutrient input in upland soil for field crops.
430 Korean Journal of Soil Science and Fertilizer Vol. 51, No. 4, 2018 Fig. 1에서의총투입량을비료종류에따라분류해본결과는 Fig. 2와같다. 무기질비료, 유기질비료및퇴비로나누어확인한결과 N, P 2 O 5 및 K 2 O의최대값은비료종류에따라무기질비료는 12.06, 8.76 및 15.27 kg 10a -1, 유기질비료는 18.45, 9.00, 5.25 kg 10a -1 였으며퇴비는 16.23, 18.33 및 21.00 kg 10a -1 으로확인되었다. 비료종류에따른 N, P 2 O 5 및 K 2 O의평균투입량은무기질비료 2.92±1.89, 1.14±1.05 및 1.88±1.62 kg 10a -1, 유기질비료는 0.90±1.27, 0.51±0.82 kg 10a -1 및 0.32±0.52 kg 10a -1, 퇴비는 2.37±2.18, 2.54±2.41 및 1.89±2.63 kg 10a -1 로확인되었다. 본결과를통해실제농가의시비되는비료종류에따라 N, P 2 O 5 및 K 2 O에기여하는비율을확인할수있었다. N의경우무기질비료가 47.2% 로가장높은비중을차지하고있었으며퇴비 38.3%, 유기질비료 14.5% 순이었다. P 2 O 5 의경우퇴비 (60.6%) > 무기질비료 (27.2%) > 유기질비료 (12.2%) 로퇴비가가장많은비율을차지하고있었고, K 2 O는퇴비 (46.2%) 무기질비료 (46.0%) > 유기질비료 (7.8%) 로퇴비와무기질비료가가장많은비율을차지하고있었다. Fig. 2. Distributions of gross nutrient input by inorganic and organic fertilizer application in upland soil for field crops. Table 1은무기질비료와부숙유기질비료의투입량을이용하여산정한 I/O ratio 결과이다. 작물종류에따라질소의 I/O ratio는 0.54-1.83으로나타났으며, 최저값 0.54는고랭지배추재배지였고 1.75는고추재배지였다. 이를통해 N 시비의경우고랭지배추는다른작물에비해무기질비료에대한의존도가높다고보여진다. P 2 O 5 및 K 2 O는최소값이각각 1.67 ( 배추 ) 및 0.11 ( 고랭지배추 ) 였으며최대값은각각 4.86 ( 고추 ) 및 2.49 ( 대파 ) 인것을확인하였다. P 2 O 5 는무기질비료보다유기질비료에의한비율이높았으며 K 2 O의경우고랭지배추를제외하고유기질비료의비율이높은것으로확인되었다. 고랭지배추의무기질비료및유기질비료의투입량이많은이유는 Lee et al. (2006) 의연구결과고랭지농가에서는적정량이상의부산물비료를사용하면서도복합비료를다량으로시용하며배추는질소의경우 1.4-1.6배, 인산의경우는 4.6-8.3배가량시용한다고보고하고있다. 또한 Joo and Lee (2011) 의연구결과경사도 5% 에서는 T-N의유출이 11.1 kg 10a -1 이었으며, 경사도 20 및 35% 에서는각각 2.92 및 4.17 kg 10a -1 이유실된다고보고하고있다. 이러한경사도에의한유실때문에경작농가에서는고랭지농업에서비료를과량으로사용한다고판단된다.
Estimation of Nutrient Balance in Field Crops Applied with Different Fertilization 431 Table 1. Organic fertilizer/ Inorganic fertilizer ratio of vegetable crops at upland fields. N P 2 O 5 K 2 O Highland Pepper Leek Garlic Radish Onion Max 1.57 18.77 11.58 12.54 11.62 37.45 1.74 Med 0.49 1.14 0.89 0.83 0.70 0.46 0.71 Min 0.08 0.00 0.00 0.00 0.00 0.00 0.00 Mean 0.54 1.75 1.27 1.47 1.09 0.74 0.92 SD 0.30 2.25 1.46 1.82 1.81 0.98 0.91 Max 5.66 45.91 25.83 79.50 26.35 205.47 96.43 Med 1.49 2.74 2.06 1.11 1.00 0.77 1.87 Min 0.28 0.00 0.00 0.00 0.00 0.00 0.00 Mean 1.74 4.86 3.64 2.65 2.19 1.67 3.71 SD 1.41 7.20 4.59 6.48 3.84 2.33 9.72 Max 0.43 17.25 28.33 17.25 19.76 28.33 21.85 Med 0.08 0.80 1.47 0.63 0.15 0.50 1.01 Min 0.01 0.00 0.00 0.00 0.00 0.00 0.00 Mean 0.11 1.80 2.49 1.81 0.74 1.45 2.41 SD 0.09 2.57 3.74 2.93 2.50 2.81 3.74 비료의사용조합방법의경우가지, 고추, 대파, 무, 배추, 생강, 양배추및양파의경우무기질비료와퇴비를혼용하여사용하는농가가대부분이었으며유기질비료의사용은무기질비료및퇴비에비해미량을사용하는것을확인하였다. 반면에고랭지배추와마늘재배의경우무기질비료및퇴비뿐만아니라유기질비료의사용도무기질비료및퇴비와비슷한수준으로시비한다는것을확인하였다. 작물종류에따라확인한결과고랭지배추재배가유기질보다무기질비료에대한비율이다른작물에비해높은것으로확인되었으며의존이높다고판단된다. 작물종류에따른비료투입량작물종류에따른비료투입량은 Table 2와같다. 각작물에따라비료투입량을작물에따라항목별로확인한결과 N 평균투입량은고랭지배추가 6.56 kg 10a -1 로가장높았으며무가 3.56 kg 10a -1 로가장낮은수치를보였다. P 2 O 5 투입량은양파가 4.07 kg 10a -1 로가장높았으며배추가 2.48 kg 10a -1 로가장낮은수치를보였다. K 2 O 투입량은고추가 4.32 kg 10a -1 로가장높았으며마늘이 1.96 kg 10a -1 로가장낮은결과를보였다. 그러나평균값이아닌작물종류에따른투입량의최대값을확인하였을때고추가 N, P 2 O 5 및 K 2 O의값이 28.65, 14.73 및 22.8 kg 10a -1 로가장높은것을확인할수있었다. 이로인해작물종류별에있어서고추의경우과잉으로비료가투입되고있는곳이많다고판단되어진다. 작물종류별양분수지예측 Table 3은작물종류에따른총투입량과작물의양분흡수량및작물의생산량을이용해양분수지를계산하였다. N에서는배추가 5.46 kg 10a -1 으로가장높은수치를보여주고있으며, P 2 O 5 및 K 2 O 에서는양파가 3.71및 3.96 kg 10a -1 으로가장높았다. 작물전체적으로현재 N, P 2 O 5 및 K 2 O가평균 3.89±1.15, 2.80±0.69 및 2.04±1.25 kg 10a -1 이과다시비되어초과양분이발생하고있는것으로판단된다. 적절한비료및퇴비의시비는토양의물리성및화학성을증대시킴으로써작물의안정적인생산을위해필수적이지만 (Made et al.,
432 Korean Journal of Soil Science and Fertilizer Vol. 51, No. 4, 2018 2002; Yun et al., 2009; Choi et al., 2010; Diacono and Montermurro, 2010; Lim et al., 2011), 과다한양분이지속적으로공급될경우작물의생육장애를초래할뿐만아니라 (Cho and Park, 2002) 축적된양분이강우등에의해수계로유입될경우 1차및 2차오염을유발할수도있다 (Lee et al., 2011). 토양의토성및경작지의환경특성에따라비료의투입량이다르므로직접적으로추후경작지의토양및경작환경조사를통해안정적인작물생산량과실제농가의환경을고려한적정비료사용량을위해토양및농업환경실태조사가이루어져야할것으로판단된다. Table 2. Fertilizer usage of vegetable crops at upland fields. (Unit : kg 10a -1 ) N P 2 O 5 K 2 O Highland Pepper Leek Garlic Radish Onion Max 13.29 28.65 15.63 19.60 9.36 11.74 137.0 Med 5.88 4.03 5.79 5.08 3.56 4.36 5.66 Min 3.32 0.24 1.26 0.72 0.99 0.0 0.85 Mean 6.56 4.67 6.09 5.84 3.56 4.57 5.80 SD 2.06 3.55 2.99 3.34 1.75 2.53 2.74 Max 7.17 14.73 15.18 13.50 6.98 7.93 13.64 Med 2.65 3.18 3.47 2.78 2.50 2.24 3.42 Min 0.90 0.33 0.06 0.0 4.8 0.0 0.0 Mean 2.95 3.65 3.83 3.59 2.50 2.48 4.07 SD 1.57 2.49 2.49 2.59 1.47 1.81 2.67 Max 7.85 22.82 17.33 19.36 6.42 11.58 20.97 Med 3.43 2.10 3.51 2.98 1.96 2.07 3.91 Min 1.83 0.16 0.42 0.21 0.54 0.0 0.30 Mean 3.78 3.06 4.32 4.02 1.96 2.72 4.87 SD 1.29 3.20 2.97 3.14 1.20 2.05 3.83 Table 3. Nutrient balances of vegetable crops at upland fields. (Unit : kg 10a -1 ) Input Output Nutrient balance Highland Pepper Leek Garlic Radish Onion N 6.50±1.82 4.67±3.55 5.80±3.01 5.62±3.38 3.09±1.76 4.50±2.58 5.61±2.92 P 2 O 5 2.70±1.33 3.65±2.49 4.00±2.70 3.32±2.44 2.38±1.77 2.44±1.84 4.08±2.89 K 2 O 3.87±1.12 3.06±3.20 3.68±2.38 3.79±3.13 2.12±1.46 2.61±2.02 4.93±4.22 N 0.86±0.24 0.58±0.34 2.52±6.39 1.39±0.86 0.85±0.24 1.15±0.40 0.86±0.54 P 2 O 5 0.29±0.08 0.18±0.10 0.84±2.13 0.47±0.29 0.33±0.09 0.50±0.13 0.38±0.24 K 2 O 1.14±0.32 1.18±0.70 1.68±4.26 1.06±0.65 1.70±0.47 2.02±0.54 0.97±0.61 N 5.64±1.93 4.09±3.60 3.28±6.65 4.23±3.48 2.24±1.72 2.98±2.47 4.75±2.73 P 2 O 5 2.42±1.34 3.48±2.51 3.16±3.02 2.85±2.39 2.05±1.74 1.93±1.79* 3.71±2.80 K 2 O 2.72±1.39 1.88±3.36 2.00±4.93 2.74±3.21 0.41±1.49 0.59±2.00 3.96±4.05
Estimation of Nutrient Balance in Field Crops Applied with Different Fertilization 433 Conclusions 본연구는각도별재배면적이가장많은노지작물을선정하고작물종류및비료종류에따른비료투입량을조사하여국내밭작물의총투입량을확인하고물질수지를통해과잉시비되는양분의양을알아보고자하였다. 국내밭작물의비료총투입량은평균 5.40±3.09, 3.50±2.54 및 3.61±2.92 kg 10a -1 로나타났으며, 비료종류에따른 N, P 2 O 5 및 K 2 O의평균투입량은무기질비료 2.92±1.89, 1.14±1.05 및 1.88±1.62 kg 10a -1, 유기질비료는 0.90±1.27, 0.51±0.82 kg 10a -1 및 0.32±0.52 kg 10a -1, 퇴비는 2.37±2.18, 2.54±2.41 및 1.89±2.63 kg 10a -1 로확인되었다. 무기질비료와부숙유기질비료의투입량을이용하여산정한 I/O ratio 결과질소는고랭지배추가 0.54로가장낮았으며, 고추가 1.75로가장높은수치를보였다. P 2 O 5 는배추가 1.67로가장낮았으며고추가 4.86으로가장높았고 K 2 O의경우고랭지배추가 1.67로최소값이었으며대파가 2.49로최대값을나타내었다. 작물종류에따른총투입량과작물의양분흡수량및작물의생산량을이용해양분수지를계산한결과 N에서는배추가 5.46 kg 10a -1 으로가장높은수치를보여주고있으며, P 2 O 5 및 K 2 O에서는양파가 3.71및 3.96 kg 10a -1 으로가장높았다. 작물전체적으로현재 N, P 2 O 5 및 K 2 O가평균 3.89±1.15, 2.80±0.69 및 2.04±1.25 kg 10a -1 이과다시비되어초과양분이발생하고있는것으로판단된다. 토양의토성및경작지의환경특성에따라비료의투입량이다르므로직접적으로경작지의토양및경작환경조사를통해안정적인작물생산량과실제농가의환경을고려한적정비료사용량을농가에교육하고초과되는양분의환경문제를야기시키며작물생육에장해를일으킬수있다는경각심을일깨워줄필요가있을것이라판단된다. Acknowledgement This study was carried out with the support of PJ0125052018 Rural Development Administration, Republic of Korea. References Cho, S.H. and T.H. Park. 2002. Effect of organic fertilizer, microorganism and seaweed extract application on growth of. J. KOWREC. 10(4):81-85. Choi, H.S., L. Xiong, W.S. Kim, K.J. Choi, Y. Lee, and S.K. Jung. 2010. Soil characteristics and leaf and bud developments with different organic fertilizers in a pear orchard. Korean J. Org. Agric. 18(3):363-375. Choi, Y.J., G.M. Gim, J.Y. Lee, K.H. Kang, and S.G. Yun. 2009. An analysis of purchasing and using fertilizer by farmers. Korean Assoc. Agric. Extension. 16(4):687-711 Diacono, M. and F. Montemurro. 2012. Long term effects of organic amendments on soil fertility. A review. Argon. Sustain. Dev. 30:401-422. Gil, S.G. 2000. Reduction of chemical fertilizer use for environmental friendly agriculture. Soil Fertilizer. 4:29-35. Jeon, B.J., S.S. Lim, K.S. Lee, S.I. Lee, J.H. Ham, S.H. Yoo, K.S. Yoon, and W.J. Choi. 2014. Understanding spatial variations of water quality using agricultural nutrient indices in Chonnam province. Korean J. Environ. Agric. 33(1):44-51. Joo, J.H. and S.B. Lee. 2011. Assessment of nutrient losses in different slope highland soils amended with livestock manure compost. Korean J. Soil Sci. Fert. 44(3):361-367.
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