• 한국산림과학회지
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• 제95권2호
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• pp.177-182
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• 2006

Little information is available on soil $CO_2$ efflux and crop yield under agroforestry systems. Soil $CO_2$ efflux, microbial biomass C, live fine root biomass, and cotton yield were measured under a pecan (Carya illinoinensis K. Koch)-cotton (Gossypium hirsutum L.) alley cropping system in southern USA. A belowground polyethylene root barrier was used to isolate tree roots from cotton which is to provide barrier and non-barrier treatments. The barrier and non-barrier treatment was randomly divided into three plots for conventional inorganic fertilizer application and the other three plots for organic poultry litter application. The rate of soil $CO_2$ efflux and the soil microbial biomass C were affected significantly (P < 0.05) by the fertilizer treatment while no significant effect of the barrier treatment was occurred. Cotton lint yield was significantly (P < 0.0 I) affected by the root barrier treatment while no effect was occurred by the fertilizer treatment with the yields being greatest ($521.2kg\;ha^{-1}$) in the root barrier ${\times}$ inorganic fertilizer treatment and lowest ($159.8kg\;ha^{-1}$) in the non-barrier ${\times}$ inorganic fertilizer treatment. The results suggest that the separation of tree-crop root systems with the application of inorganic fertilizer influence the soil moisture and soil N availability, which in tum will affect the magnitude of crop yield.

• Applied Biological Chemistry
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• 제7권
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• pp.45-52
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• 1966

This study was carried out to determine how the water soluble, the available $P_2O_5$ and urea-N would change in the course of time, when the mixtures of calcium superphosphate and urea with lime for fertilizer which occurred in Korea and largely contained calcium carbonate were made. Three kinds of materials, i. e., calcium superphosphate, urea and lime for fertilizer were used in this study. Three kinds of mixed fertilizer, i. e., A, B and C were made up by mixing these materials to satisfy the following formula. $$1)\;Ca(H_2PO_4)_2+CaCO_3+CO(NH_2)_2{\rightarrow}$$$$Ca_2H_2(PO_4)+H_2CO_3+NH_3$$ $$2)\;Ca(H_2PO_4)_2+CaCO_3+CO(NH_2)_2{\rightarrow}$$$$Ca_3(PO_4)_2+H_2CO_3+NH_3$$ $$3)\;Ca(H_2PO_4)_2+CaCO_3+CO(NH_2)_2{\rightarrow}$$$$Ca_3(PO_4)_2+H_2CO_3+CaCO_3+NH_3$$ A,B and C were placed in desiccators respectively a six month period. During the time of storage, the water soluble, the available phosphoric acid and urea-N were measured once a month, seven times with the control measurement. The results may be summarized as follows. 1. None of A, B and C showed any change in the urea-N with the lapse of time. This fact indicated that the combination of calcium superphosphate and urea with lime for fertilizer was not unfavourable. 2. A, B and C decreased in the amount of water soluble $P_2O_5$ with the passage of time. This fact indicated that the mixing of calcium superphosphate and urea with lime for fertilizer was unfeasible. 3. The available $P_2O_5$ in any of A,B and C did not undergo a change as time went by. This fact suggested that the combination of calcium superphate and urea with lime for fertilizer was favourable.

• 한국작물학회지
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• 제55권3호
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• pp.268-274
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• 2010

The aim of our study was to investigate the interactive effects of container size and nutrient supply on plant growth, chlorophyll synthesis, transpiration, $CO_2$ assimilation, water use efficiency (WUE), and nutrient uptake of vinca plant (Catharanthus roseus). A complete experiment utilizing four concentrations of fertilizer and three volumes of containers was conducted. As the container size was increased, the plant height, leaf area, and dry weight of vinca significantly increased regardless of fertilizer level. The leaf area and dry weight of vinca were highly sensitive to the container size. However, the chlorophyll contents of vinca 20 days after the transplant significantly increased with decreasing container sizes and increasing fertilizer concentrations. Significant differences in transpiration and $CO_2$ assimilation occurred with the use of differentfertilizer solutions, but the highest values for transpiration and $CO_2$ assimilation were in plants grown in the 15 cm-diameter containers. The highest water use efficiency was observed in the plants grown in 10 cm-containers with 4 dS/m of fertilizer, and there were no significant differences in WUE values among container sizes with fertilizer concentrations of 0, 1, or 2 dS/m. No significant difference in nutrient uptake was observed among the fertilizer levels or among the container sizes. However, at a fertilizer concentration of 4 dS/m, the uptake of several nutrients, including N, P, K, Ca, Mg, B and Fe, was higher in small containers than in larger ones.

• 한국토양비료학회지
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• 제48권5호
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• pp.340-350
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• 2015

This experiment was carried out to find out the mitigation of greenhouse gases (GHGs) emission and changes of soil carbon contents in the cropland. In order to minimize the soil disturbance, this study was conducted without crop cultivation at the pots treated with different biomass. Different biomass was buried in the soil for 12 months. Decomposition rates of expander rice hull, pig manure compost and carbonized rice hull were 18%, 11~11.5% and 0.5~1.2%, respectively. It was appeared that carbonized rice hull was slightly decomposed. No difference was shown between chemical fertilizer treatment plot and non-application plot. It was appeared that soil carbon content in the non chemical fertilizer application plot was high when compared to its chemical fertilizer. Its content at soil depth of 20 cm more decreased than the upper layer of soil. Accumulative emission of $CO_2$ with different treatments of biomass was highest of 829.0~876.6 g $CO_2m^{-2}$ in the application plot of PMC (Pig Manure Compost) regardless of chemical fertilizer treatment during 16 months of experiment. However, the emission for expander rice hull treatment plot was lowest of 672.3~808.1 g $CO_2m^{-2}$. For application plot of the carbonized rice hull, it was shown that non chemical fertilizer plot, 304.1 mg $N_2Om^{-2}$, was higher than the chemical fertilizer treatment, 271.6 mg $N_2Om^{-2}$. Greenhouse gas emissions in the PMC treatment were highest of 0.94 ton $CO_2eqha^{-1}yr^{-1}$. However, it was estimated to be the lowest in the expander rice hull treatment.

• Journal of Ecology and Environment
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• 제35권4호
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• pp.307-311
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• 2012

This study was conducted to evaluate the dynamics of soil respiration (total soil and heterotrophic respiration) following fertilizer application in red pine forests. Fertilizer (N:P:K = 113:150:37 kg/ha), which reflects current practices in Korean forest, was applied in April 2011, and total soil and heterotrophic respiration rates were monitored from April 2011 to March 2012. Monthly variation of total soil and heterotrophic respiration rates were similar between the fertilizer and control treatments, as soil temperature was the dominant factor controlling the both rates. Total soil respiration rates during the study period were not significantly different between the fertilizer (0.504 g $CO_2\;m^{-2}\;h^{-1}$) and control (0.501 g $CO_2\;m^{-2}\;h^{-1}$) treatments. However, the proportion of heterotrophic respiration was higher in the fertilizer (78% of total soil respiration rates) than in the control (62% of total soil respiration rates) treatments. These results suggest that current fertilizer practices in Korea forest soil do not substantially affect total soil respiration rates.

• Journal of Microbiology and Biotechnology
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• 제32권10호
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• pp.1292-1298
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• 2022

Soil autotrophic bacterial communities play a significant role in the soil carbon (C) cycle in paddy fields, but little is known about how rhizosphere soil microorganisms respond to different long-term (35 years) fertilization practices under double rice cropping ecosystems in southern China. Here, we investigated the variation characteristics of rhizosphere soil RubisCO gene cbbL in the double rice ecosystems of in southern China where such fertilization practices are used. For this experiment we set up the following fertilizer regime: without any fertilizer input as a control (CK), inorganic fertilizer (MF), straw returning (RF), and organic and inorganic fertilizer (OM). We found that abundances of cbbL, 16S rRNA genes and RubisCO activity in rhizosphere soil with OM, RF and MF treatments were significantly higher than that of CK treatment. The abundances of cbbL and 16S rRNA genes in rhizosphere soil with OM treatment were 5.46 and 3.64 times higher than that of CK treatment, respectively. Rhizosphere soil RubisCO activity with OM and RF treatments increased by 50.56 and 45.22%, compared to CK treatment. Shannon and Chao1 indices for rhizosphere soil cbbL libraries with RF and OM treatments increased by 44.28, 28.56, 29.60, and 23.13% compared to CK treatment. Rhizosphere soil cbbL sequences with MF, RF and OM treatments mainly belonged to Variovorax paradoxus, uncultured proteobacterium, Ralstonia pickettii, Thermononospora curvata, and Azoarcus sp.KH33C. Meanwhile, cbbL-carrying bacterial composition was obviously influenced by soil bulk density, rhizosphere soil dissolved organic C, soil organic C, and microbial biomass C contents. Fertilizer practices were the principal factor influencing rhizosphere soil cbbL-carrying bacterial communities. These results showed that rhizosphere soil autotrophic bacterial communities were significantly changed under conditions of different long-term fertilization practices Therefore, increasing rhizosphere soil autotrophic bacteria community with crop residue and organic manure practices was found to be beneficial for management of double rice ecosystems in southern China.

• 농업과학연구
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• 제41권4호
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• pp.275-281
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• 2014

The ozone depletion has caused plants to be exposed to an increased penetration of solar ultraviolet-B (UV-B) radiation. Enhanced UV-B radiation may have influence on biological functions of plant in many aspects including inhibition of photosynthesis. It is evident that UV-B can potentially impair the performance of all three main component processes of photosynthesis, the photophosphorylation reactions of the thylakoid membrane, the $CO_2$-fixation reactions of the Calvin cycle and stomatal control of $CO_2$ supply. Owing to these depressed reactions, the production and allocation of carbohydrates might be markedly affected, and therefore, the growth and development of plant are distinctly reduced. In this review paper, we provide basic theory and further researches in terms of photosynthesis and carbohydrate synthesis in response to elevated UV-B radiation.

• 한국토양비료학회지
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• 제41권6호
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• pp.408-414
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• 2008

온실가스의 농도 증가에 따른 지구온난화로 기후변화 및 환경적 영향이 증가하고 있으며, 다른 산업 분야별 온실가스 저감 노력이 계속 되고 있다. 농경지에서 온실가스 배출 저감 및 탄소 수지 연구를 통하여 농업생산 활동이 온실가스를 배출 이외에도 탄소를 고정 또는 축적 기능이 있다는 것을 밝히고자 하였다. 먼저 작물 작부체계에 따른 탄소 수지를 평가하고자 대기 중 이산화탄소 자동측정 장치를 개발하여 $CO_2$ 함량 변화를 조사하였다. 이를 통해 작물 생태계 내에서 보리-콩 및 보리-고추 작부체계의 생태계 순 생산량이 화학비료를 사용한 NPK 처리구와 돈분 퇴비를 추가한 NPK+돈분 퇴비 처리구를 두고 $CO_2$ 함량을 조사하였다. 보리-콩 작부체계의 NPK 및 NPK+퇴비처리구는 각 $6.3,\;10.6ton\;CO_2\;ha^{-1}$ 그리고 보리-고추작부체계에서는 $12.0,\;13.2ton\;CO_2\;ha^{-1}$이 축적된 것 으로 나타났다. 토양 탄소수지 평가에서는 보리-콩 작부체계에서 토양 유기 탄소 축적은 $0.7ton\;C\;ha^{-1}$, 보리-고추에서 $0.5ton\;C\;ha^{-1}$이 토양 중에 저장하였다. 이로써 농경지가 탄소 저장원 역할을 하는 것으로 해석할 수 있다.

• 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.

• 한국환경농학회지
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• 제30권2호
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• pp.99-104
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• 2011

BACKGROUND: Application of urea may increase $CO_2$ emission from soils due both to $CO_2$ generation from urea hydrolysis and fertilizer-induced decomposition of soil organic carbon (SOC). The objective of this study was to investigate the effects of increasing urea application on $CO_2$ emission from soil and mineralization kinetics of indigenous SOC. METHODS AND RESULTS: Emission of $CO_2$ from a soil amended with four different rates (0, 175, 350, and 700 mg N/kg soil) of urea was investigated in a laboratory incubation experiment for 110 days. Cumulative $CO_2$ emission ($C_{cum}$) was linearly increased with urea application rate due primarily to the contribution of urea-C through hydrolysis to total $CO_2$ emission. First-order kinetics parameters ($C_0$, mineralizable SOC pool size; k, mineralization rate) became greater with increasing urea application rate; $C_0$ increased from 665.1 to 780.3 mg C/kg and k from 0.024 to 0.069 $day^{-1}$, determinately showing fertilizer-induced SOC mineralization. The relationship of $C_0$ (non-linear) and k (linear) with urea-N application rate revealed different responses of $C_0$ and k to increasing rate of fertilizer N. CONCLUSION(s): The relationship of mineralizable SOC pool size and mineralization rate with urea-N application rate suggested that increasing N fertilization may accelerate decomposition of readily decomposable SOC; however, it may not always stimulate decomposition of non-readily decomposable SOC that is protected from microbial decomposition.