• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.279-281
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• 2003

This study is intended to give information on agricultural nonpoint source pollution and transport related to fertilizer application and irrigation practice. Field-simulated soil columns were set up and leaching studies on fertilizer components such as nitrogen and phosphorus were performed. Nitrogen and phosphorus in the leachate showed different trends in each column and nonpoint source pollution in agricultural areas may be expected to depend on planted crops, soil conditions, and climate as well as irrigation and fertilizing management.

• Journal of Plant Biology
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• 제14권3호
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• pp.43-46
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• 1971

Losses of nitrogenin the gaseous form were determined with closed systems in the filed under different vegetation types. Ammonia volatilization was greatest from the pine stand, and least from the sod stand, and was greatly reduced in all three sites in the rainy season due to the low temperature. There were only insignificant differences in the nitrogen dioxide volatilization from the soil of the three vegetation types. Losses of ammonia and nitrogen dioxide at various soil depth also showed little variation. Evidently the microbial activity responsible for the $NO_2$ loss was relatively unaffected by the changes in temperature and soil moisture content during the investigation.

• Journal of Korean Society for Atmospheric Environment
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• 제14권E호
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• pp.9-17
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• 1998

Oxides of nitrogen play important roles in atmospheric chemistry. Soil has been recognized as a major natural source of NO, and its emission depends on soil parameters such as soil nitrogen availability, soil moisture and temperature. It is necessary to understand effects of these controlling parameters on soil NO emission. In order to understand soil moisture effects on NO emission, variations of NO concentration and existence of its equilibrium concentration were observed from ammonium fertilized Japanese upland soil prepared for different soil moisture conditions. The closed chamber technique was employed for this study. The significant increases in NO with soil moisture were found. Maximum was occurred at sample ID4 (55% of water-filled pore space (WFPS)), but it decreased as soil moisture increased. No significant NO concentration was emitted from soil sample without fertilizer, but there was significant NO in fertilized soil samples. The magnitudes of NO from soil increased with time and reached at steady state within ten minutes approximately. These results suggest that nitrogen input from fertilizer takes charge in the first step of sharp increase in NO emission, and then soil moisture becomes important factor to control NO emission from the soils. NO concentrations from soil were compared to those one-day after the experiment. Results from the comparison analysis suggest that the soil NO flux might have been stimulated by soil disturbances like mixing, and this is much more effective in dry soils rather than in wet soils. It was found that much less NO came out from soils after a day; suggesting that most of NO was released from the soils within a day after fertilizer application during our experiment. The length of NO releasing time span may depend on the amounts of fertilizer applied, soil moisture condition, and other soil physical parameters.

• 한국토양비료학회지
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• 제43권3호
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• pp.349-355
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• 2010

본 연구는 토양검정시비량에 준하는 비료량을 기준으로 그 처리량을 가감하여 점적관수로 관비하였을 경우 참외의 생육과 수량에 미치는 영향을 조사하고 참외의 생육단계별 양분흡수특성을 검토하여 관비재배 시에 생육단계별 참외 질소시비기준을 설정하고자 수행되었다. 이를 위하여 토양검정 질소시비량 ($N:P_2O_5:K_2O$=249:408:315 kg $ha^{-1}$)의 0배, 0.5배, 1.0배, 1.5배에 해당하는 질소량을 8회로 나누어 정식 후 10일 간격으로 관비하였다. 점적관비에 의한 참외 생육기간 중 참외의 생육, 수량 및 무기양분흡수 등을 조사하였다. 잎, 줄기 중 T-N의 함량은 정식 30일까지 증가한 후 점점 감소하는 경향을 보였고, 질소관비량이 증가할수록 T-N함량도 증가하는 경향을 볼 수 있었다. 질소관비량이 증가할수록 참외의 생체중과 질소흡수량은 증가하였지만 총수량 및 상품수량은 그렇지 않았다. 총수량과 상품수량은 검정시비 0.5배구에서 각각 44,550 kg $ha^{-1}$와 42,880 kg $ha^{-1}$로 가장 높았다. 또 상품과율도 0.5배구에서 95%로 가장 높았다. 결과적으로 과실의 총수량, 상품수량, 상품과율 등을 고려할 때, 검정시비 0.5배구에 해당하는 질소량의 관비가 참외의 생육 및 수량 증가에 가장 효과적인 것으로 판단된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 총회 및 춘계학술발표회
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• pp.451-454
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• 2003

Nonpoint source pollution of groundwater and subsurface water from irrigated agriculture is a major concern in many areas. In this study we aimed to investigate the effect of the water applied by irrigation in agricultural area on the transport of nitrogen and phosphorus originated from fertilizers applied to the surface of soil in agricultural activities. We first conducted investigation on the resdual concentrations of soil N and P in a selected agricultural area. And simulating the target area by column studies in the laboratory leaching extent of various components from the composite and urea fertilizers applied on the soil surface during irrigation was studied. Infiltration of water enhanced the leaching of nitrogen and phosphorus in both the rice paddy field soil and the patch soil. The downward N and P transport with infiltrating water was more pronounced in the patch soil column and the increased residual concentrations of N and P in the lower sections in the patch soil column was found with time.

• 한국토양비료학회지
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• 제20권3호
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• pp.261-268
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• 1987

논상태(狀態)의 토양(土壤)에서 유기물(有機物)의 종류(種類), 질소비종(窒素肥種) 및 시비량(施肥量)을 달리했을 때 광합성(光合成) 및 타양성질소고정미생물(他養成窒素固定微生物)에 의한 생물학적(生物學的) 질소고정량(窒素固定量)과 Kjeldahl 분석(分析)에 의한 토양중(土壤中) 전질소함량(全窒素含量) 변화차이(變化差異)를 알고저 초자실(硝子室)에서 60일(日) 담수시험(湛水試驗)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 각종시용유기물중(各種施用有機物中) 탄소(炭素) 1mg당(當) 생물질소(生物窒素) 고정량(固定量)은 glucose 0.13mg, 볏짚 0.09mg, 그리고 양송이 폐상퇴비와 보리짚은 0.07mg이였다. 2. 토양종류(土壤種類)에 따른 질소고정량(窒素固定量)은 질소비종(窒素肥種)에 따라서 상이(相異)했으며 시비량(施肥量)이 증가(增加)할수록 감소(減少)했는데 감소(減少)의 정도(程度)는 유안(硫安)보다 요소시용시(尿素施用時) 현저(顯著)하였다. 3. 광조건별(光條件別) 질소비종(窒素肥種) 및 시비량(施肥量)에 따른 질소고정량(窒素固定量)은 사질토양(砂質土壤)에서 유안(硫安)이 요소(尿素)보다 증가(增加)되었으며 전질소고정량중(全窒素固定量中) 75%는 광합성미생물(光合成微生物)에 의하여 그리고 25%는 타양성질소고정미생물(他養性窒素固定微生物)에 의하여 고정(固定)되었다고 추정(推定)할 수 있었다. 그러나 식질토양(埴質土壤)에서는 광조건(光條件)과 질소비종간(窒素肥種間)에 뚜렷한 차이(差異)는 보이지 않했다. 4. 시험전후토양(試驗前後土壤)의 질소함량(窒素含量)을 보면 사질토양(砂質土壤)은 처리(處理)에 관계(關係)없이 시험후(試驗後) 토양(土壤)의 질소(窒素)가 현저(顯著)히 감소(減少)되었는데 그 정도(程度)는 요소시용구(尿素施用區)의 광차단조건(光遮斷條件)에서 현저(顯著)하였다. 한편 식질토양(埴質土壤)에서 비종간(肥種間)에는 큰차이(差異)를 볼 수 없었으나 광차단조건(光遮斷條件)에서 질소(窒素)의 감소(減少)가 현저(顯著)하였다. 5. Acetylene 환원법(還元法)에 의한 생물질소고정량(生物窒素固定量)과 Kjeldahl 분석(分析)에 의한 전질소함량변화차이(全窒素含量變化差異)는 평균(平均) 6:1의 비율(比率)을 보였다.

• 한국유기농업학회지
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• 제8권2호
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• pp.97-110
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• 2000

An organic agriculture should be managed by mixed farming in farm unit as a closed recycling system. Due to restricted purchased of fertilizers from outside, organic farmer has to deal with limited amount of nutrient source in farm unit. Especially the supply of the essential nutrient, nitrogen, mostly depends on legumes fixing nitrogen optimizing the site-adapted crop rotation. Dynamics of humus and metabolic plant carbon and active soil carbon compartment in active and passive humuspool by rotation system was explained, and dynamics of potentially mineralizable nitrogen in organic nitrogen and biomass was discussed. It was also discussed comparison of ammonia emission, potential greenhouse effect, primary energy input, acidification potential, CO2 emission between organic and conventional farming, the nitrate-nitrogen dynamic in the soil profile by organic, integrated and conventional farming system. In conclusion, it was suggested for Korean Organic Agriculture that the importance of legumes and green manures in rotation system for increase/maintenance of soil ferfility, and was pointed out the need of investment for environment impact of Korean organic farming implement.

• 한국농공학회논문집
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• 제63권3호
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• pp.35-45
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• 2021

Digestate or slurry produced from anaerobic digestion is mostly applied to crop lands for its disposal and recovering nutrients. However, minimizing nitrogen losses following field application of the digestate is important for maximizing the plant's nitrogen uptake and reducing environmental concerns. This study was conducted to assess the effects of three different biogas digestate application techniques (sawdust mixed with digestate (SSD), the hole application method (HA), and digestate injected in the soil (SD)) on nitrate leaching potential in the soil. A pot laboratory experiment was conducted at room temperature of 25 ± 2 ℃ for 107 days. The experimental results showed that sawdust application method turned out to be appropriate for quick immobilization of surplus N in the form of microbial biomass N, reflecting its lower total nitrogen and NH₄-N contents and low pH. The NH₄-N and total nitrogen fate in the soil fertilized with manure showed no statistically significant (p > 0.05) differences between the different methods applied during the incubation time under room temperature. In contrast, NO₃-N concentration indicates significant reduction in sawdust treatment (p < 0.05) compared to the control and other application methods. However, the soil sawdust mixed with digestate was more effective than the other methods, because of the cumulative labile carbon contents of the amendment, which implies soil net N immobilization.

• The Korean Journal of Ecology
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• 제19권5호
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• pp.375-383
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• 1996

Effects of forest fire on soil nutrients in pine forests were studied in Dosong, Kangwon Province in Korea. Soil samples were collected from burned sites and unburned sites (control) at Kusungri, Sampori and Wunbongri. Soil pH in burned sites was higher than that in unburned sites. Soil organic matter did not differ significantly between the burned and unburned sites. Concentrations of available phosphorus in burned soils were about 3 times higher than those in unburned sites. Also, concentrations of ammonium nitrogen were markedly increased in burned sites contrary to those of nitrate nitrogen. Total nitrogen, however, showed no significant difference between the sites. Concentrations of cations, calcium and magnesium, in burned sites were also significantly increased. Thus, even though forest fire removed the aboveground biomass of pine forests, inorganic nutrients added from ash may play a great role for growth of sprouts and seedlings after forest fire.

• 한국토양비료학회지
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• 제33권6호
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• pp.384-392
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• 2000

토양중 질산태 질소 함량이 $14{\sim}225mg\;kg^{-1}$의 범위를 갖는 시설재배지 9개 토양에서 배추를 공시작물로 하여 무비구, 3요소 표준시비량의 50%구, 100%구 및 150%구의 4개 시비수준에서 포트재배로 수량반응, 비료효과 및 시비효율 등을 검토하였다. 무비구 배추 건물중과 토양의 질산태 질소 함량은 유의성 있는 정의 상관을 나타냈고 시비구와 무비구의 건물중, 질소흡수량 및 질산태 질소흡수량의 차이로 평가한 비료효과 및 시비효율과는 유의성 있는 부의 상관을 보였다. 질산태 질소함량에 따른 시비수준별 건물중 반응의 관계로부터 표준시비량이 적용되는 질산태 질소의 하한기준은 $50mg\;kg^{-1}$ 미만으로 추정되었고, 질산태질소 함량과 비료효과 및 시비효율과의 회귀관계로부터 평가된 무비 재배를 위한 질산태 질소 함량은 $200mg\;kg^{-1}$ 이상으로 추정되었다. 따라서 시설재배지 토양중 질산태 질소 함량 $50mg\;kg^{-1}$에서 $200mg\;kg^{-1}$ 범위는 질소 표준시비량에 대한 비율로서 추천식은 $Y=-0.6667{\chi}+133.33$ 이었다 (Y:질소 표준시비량에 대한 %, ${\chi}$: 시험전 토양의 $NO_3-Nmg\;kg^{-1}$).