• 한국토양비료학회지
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• 제48권1호
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• pp.22-29
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• 2015

The objectives of this study were to monitor the changes in soil solution nutrients and to evaluate their effect on rice uptake and yield. The changes of chemical characteristics of paddy soil solution were examined from the 58th fertilization experiment in which the continuous rice cropping experiment started in 1954 at the National Academy of Agricultural Science. The treatments were no fertilization (No fert.), inorganic fertilization (NPK), inorganic fertilizer plus rice straw compost (NPKC) and inorganic fertilizer plus silicate and lime fertilizer as a soil amendment (NPKCLS). The fertilizers were added at rates of standard fertilizer application rate in which nitrogen (N), phosphate ($P_2O_5$), potassium ($K_2O$), and sililcate ($SiO_2$) were applied at rates of $75{\sim}150kg\;ha^{-1}$, $70{\sim}86kg\;ha^{-1}$, $75{\sim}86kg\;ha^{-1}$, and $7.5Mg\;ha^{-1}$ respectively and lime was applied to neutralize soil acidity until 6.5. Average Electrical Conductivity (EC) of soil solution in NPKCLS and NPKC ranged from 1.16 to $2.00dS\;m^{-1}$. The $NH{_4}^+$ and $K^+$ levels in NPKCLS and NPKC were higher than that of the other treatments, due to high supply power of rice straw compost. The content of $H_3SiO{_4}^-$ was higher in NPKCLS because of silicate application. The dominant ions in soil solution were $Ca^{2+}$, $Mg^{2+}$ and $Na^+$ among cations and $HCO{_3}^-$, $SO{_4}^{2-}$, and $Cl^-$ among anions in all treatments. The continuous application of inorganic fertilizers plus rice straw compost (NPKC) and silicate fertilizer (NPKCLS) led to the changes of various chemical composition in soil solutions. Also, they had a significant impact on the improvement of rice inorganic uptake and grain yield. Especially, inorganic uptake by rice in NPKC and NPKCLS significantly increased than those in NPK plot; 14~46% for T-N, 32~36% for P, 43~57% for K, and 45~77% for Si. Therefore, the combined application of inorganic fertilizers with organic compost as a soil amendment is considered as the best fertilization practice in the continuous rice cropping for the improvement of crop productivity and soil fertility.

• 한국토양비료학회지
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• 제46권3호
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• pp.223-229
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• 2013

Sustainability index was calculated to determine the best management for rice productivity under long-term inorganic fertilizer management's practices. It is based on nutrient index, microbiological index and crop index related to sustainability as soil function. Indicators for calculating sustainability index were selected by the comparison of soil properties and rice response in paddy soil with fertilization. Total twenty two indicators were determined to assess nutrient index, microbiological index and crop index in order to compare the effect of different fertilization. The indices were applied to assess the sustainability with different inorganic fertilizer treatments such as control, N, NK, NP, NPK, NPK+Si, and NPK+Compost. The long-term application of compost with NPK was the highest sustainability index value because it increased nutrient index, microbial index and crop index. The use of chemical fertilizers resulted in poor soil microbial index and crop index, but the treatments like NP, NPK, and NPK+Si were maintained sustainability in paddy soil. These results indicate that application of organic and chemical fertilizer could be a good management to improve rice sustainability in paddy soil.

• 한국토양비료학회지
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• 제46권6호
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• pp.474-481
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• 2013

Understanding the microbial community structure of agricultural soils is important for better soil management in order to improve soil quality. Phospholipid fatty acid analysis has been popularly used in determining the microbial community structure in different ecosystems. The microbial community structure of paddy soil under long-term fertilizer treatments was investigated after 45 years using PLFA analysis. Treatments were control (no fertilization, Con), compost (COM), NPK, NPK+compost (NPKC), PK, NK, and NP. Soil chemical properties were mainly affected by the addition of compost and inorganic P fertilizer. Total nitrogen and organic matter contents were significantly higher in treatments with compost while available $P_2O_5$ and exchangeable calcium were significantly higher in treatments with added inorganic P fertilizer. It was found that microbial communities were responsive to the different fertilizer treatments. PLFA results showed that the soils were dominated by gram-negative bacteria, followed by the actinomycetes, then gram-positive bacteria, and fungi. Principal component analysis of the soil chemical properties and PLFA composition proved to be a more reliable tool because it was more responsive to the changes in soil chemical properties.

• 한국토양비료학회지
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• 제49권5호
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• pp.584-588
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• 2016

The current study was carried out to investigate total and inorganic arsenic (As) concentrations in 112 rice samples (husked rice and polished rice) grown around the abandoned mining areas and to estimate the potential health risk through dietary intake of rice in Korea. Mean concentrations of total As in husked rice and polished rice were 0.23 and $0.13mg\;kg^{-1}$, respectively. Also, average inorganic As concentrations in husked rice and polished rice were 0.09 and $0.05mg\;kg^{-1}$, respectively. These levels are lower than the standard guideline value ($0.2mg\;kg^{-1}$) for inorganic As in polished rice recommended by Korea Ministry of Food and Drug Safety and Codex. For health risk assessment, the average values of cancer risk probability was $5.7{\times}10^{-5}$ which was less than the acceptable cancer risk of $10^{-6}{\sim}10^{-4}$ for regulatory purpose. Also, hazard quotient values were lower than 1.0. Therefore, these results demonstrated that human exposure to inorganic As through dietary intake of rice collected from abandoned mining areas might not cause adverse health effects.

• 한국토양비료학회지
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• 제44권6호
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• pp.1279-1285
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• 2011

본 연구를 통하여 우리나라 대표적인 농작물 47개의 탄소배출량을 산정하였다. 또한 농작물 생산 시 주요 요소로 투입되는 무기화학비료의 기여도 분석을 통하여 무기화학비료가 차지하는 탄소배출량을 정확하게 파악하였다. 농작물 중 시설감귤의 탄소배출량이 $5.78E+00kg\;CO_2\;eq.\;kg^{-1}$으로 47개 작물 중 가장 높았으며 시설포도 $4.61E+00kg\;CO_2\;eq.\;kg^{-1}$, 착색단고추 $4.34E+00kg\;CO_2\;eq.\;kg^{-1}$, 인삼 $4.23E+00kg\;CO_2\;eq.\;kg^{-1}$, 시설고추 $4.04E+00kg\;CO_2\;eq.\;kg^{-1}$ 순으로 나타났다. 다음으로 농작물 1 kg 생산 시 발생하는 탄소배출량 중 무기화학비료의 기여도는 생산단계, 사용단계를 모두 포함하여 평균 25.19%를 차지하는 것으로 분석되었다. 정부의 정책, 정부 및 기업의 연구 개발을 통한 고품질 저탄소 비료 생산 보급과 같은 노력이 함께 이루어진다면 농업분야의 온실가스 감축에 큰 역할을 할 것으로 기대된다.

• 한국토양비료학회지
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• 제44권6호
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• pp.1118-1123
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• 2011

비료 및 토양개량제를 장기간 시용한 벼 재배포장에서 토양 중 유효규산 함량 분포 특성과 벼 생육량 차이를 구명하고자 수행하였다. 42년 동안의 실험에서 규산질 비료의 시용은 토양의 유효규산 함량을 최대 $333mg\;kg^{-1}$까지 증가시켰고, 표토뿐만 아니라 심토에까지 영향을 주어 규산이 축적되었다. 또한, 벼의 규산 흡수량은 3요소구에 비해 볏짚퇴비를 시용한 구에서는 64%, 볏짚퇴비와 규산질비료를 병용하여 시용한 구에서는 98%를 더 흡수하였다. 벼의 수량도 규산질비료를 시용한 구에서는 37~47% 정도 크게 증가하는 것으로 나타났다. 본 연구결과를 통해서 볼 때 무기질 비료와 더불어 유기질비료 및 규산질비료를 혼용하는 것은 토양비옥도를 향상시키고, 비료의 이용 효율을 향상시키는 방법 중에 하나로 생각되었다.

• 유기물자원화
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• 제8권1호
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• pp.103-108
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• 2000

2001년부터 정수장에서 발생하는 유기성오니의 직매립이 금지됨에 따라 이의 처리비용이 매우 증가할 것으로 판단되어 본 연구에서는 정수장 슬러지를 Chemical 및 Hydrothermal법을 사용하여 농업 및 임업용 비료로 재활용 할 수 있는 방법을 찾고자 진행하였고, 그 결과 두 방법 모두 유기물 및 유해 중금속을 제거할 수 있었으며 안정화된 무기질 비료를 제조할 수 있었다.

• 한국농공학회논문집
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• 제63권4호
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• pp.13-21
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• 2021

The feasibility of HWS for agricultural use was analyzed through a crop cultivation test to utilize the hydroponic waste solution (HWS) generated from the nutriculture greenhouse. The fertilizing effect of HWS was assessed on the basis of the inorganic nitrogen (N) mostly existed in HWSs, and nitrogen (urea) fertilizer. Lettuce was selected as the target crop influenced by the soil treatment and also for the crop cultivation test. Thus, the change in growth characteristics of lettuce and that in chemical characteristics of the soil were investigated. In terms of the growth of lettuce, the C control group with 70% nitrogen (urea) fertilizer and 30% HWS and the D control group with 50% nitrogen (urea) fertilizer and 50% HWS were more effective than the practice control group (B) with 100% nitrogen (urea) fertilizer. The results of this study confirmed the combined applicability of the chemical fertilizer and HWS for crop cultivation. Because NO₃-N present in HWS has a high possibility of leaching into the soil, its applicability as a fertilizer has been considered to be relatively low in Korea. However, if an appropriate mixing ratio of urea fertilizer and HWS could be applied, the problems associated with leaching of nitrate nitrogen could be reduced with beneficial effects on crop cultivation. Thus, future studies are required on the treatment effect of HWS with repeated cultivation, impact assessment on the surrounding environment, and appropriate fertilization methods using nitrogen (urea) fertilizer and HWS. These studies would facilitate the sustainable recycling of HWS.

• 한국토양비료학회지
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• 제33권6호
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• pp.393-397
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• 2000

퇴비의 시용량에 따른 사과의 수량과 토양화학성에 미치는 영향을 조사한 결과는 다음과 같았다. 사과원에 퇴비시용량의 증가에 의해 토양중의 인산함량 및 치환성 양이온의 함량이 증가하였으나, 유기물은 거의 변화가 없었다. 퇴비의 시용량이 증가할수록 사과의 수량은 증가하였으나, 경도 및 당도의 차이는 없었다. 화학비료를 감비처리하고 퇴비의 시용량을 높인 결과 퇴비의 시용량이 증가함에 따라 토양 중 유기물 및 Ca의 함량은 증가하였다.

• 한국환경농학회지
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• 제19권5호
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• pp.375-381
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• 2000

Quantifying the changes of soil microbial biomass and activity of enzymes are important to understand the dynamics of active soil C and N pools. The dynamics of soil microbial biomass C and N and the activity of enzymes over entire growth period of soybean-(Glycine max (L) Merr.)-wheat (Triticum aestivum L.) sequence on a Typic Haplustert as influenced by organic manure and inorganic fertilizer N were investigated in a field experiment. The application of farmyard manure at 4 to 16 $Mg{\cdot}ha^{-1}\;y^{-1}r^{-1}$ along with fertilizer nitrogen at 50 or 180 $kg{\cdot}ha^{-1}$ increased the mean soil microbial biomass from 1.12 to 2.05 fold over unmanured soils under soybean-wheat system. Irrespective of organic and chemical fertilizer N application, the soil microbial biomass was maximum during the first two months at active growing stage of the crops and subsequently declined with crop maturity. The mean annual microbial activity was significantly increased when manure and chemical fertilizer at 8 $Mg{\cdot}ha^{-1}$ and 50/180 N $kg{\cdot}ha^{-1}$, respectively were applied. The C turnover rate decreased by 47 to 72 % when the level of farmyard manure was increased from 4 to 8 and 16 $Mg{\cdot}ha^{-1}$. There were significant correlations between biomass C, available N, dehydrogenase, phosphatase and yield of the crops.