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        검색결과 731

        642.
        2012.02 서비스 종료(열람 제한)
        2012년 11월 카타르 도하에서 열린 유엔 기후변화 당사국총회 COP18 장관급회의에서는 올해 말 그 시한이 종료되는 도쿄의정서를 대신할 ‘도하합의’를 도출하였다. 2020년까지 교토의정서를 연장하고, 모든 선진국과 개발도상국이 같이 적용받는 구속력 있는 온실가스 감축안을 2015년까지 만들기 위한 기반을 조성하자는 내용이 주요골자이다. 그간 우리나라는 2010년을 기준으로 세계 이산화탄소 배출량의 1.7%를 차지하고 세계에서 8번째로 이산화탄소를 많이 배출하는 국가가 되었다. 이에 2015년 합의될 온실가스 규제에서 우리도 상당부분 배출량감소를 요구받을 전망이다. 온실가스를 발생시키는 다양한 경로 중의 하나는 산불발생으로 생성되는 산림의 바이오매스 연소이다. 교토의정서 이후 각국은 산불발생으로 인해 유발되는 온실가스인 이산화탄소와 비이산화탄소의 정량적이고 과학적인 방법을 연구 개발하고 있다. IPCC(International Panel on Climate Change)는 접근방법과 기본자료를 이용하여 배출량을 분석하는 수준1과, 국가고유활동 자료나 배출계수를 이용하여 배출량을 분석하는 수준 2, 국가 고유자료와 방법 모두를 이용하는 수준3을 제시하는데 우리나라도 수준 2나 3의 단계로 진입하는 다각도의 노력을 벌이고 있다. 본 연구는 우리나라 고유 배출계수 개발을 위해, 수관화의 위험이 높은 소나무의 바이오매스 연소에 따른 CO2/non-CO2 배출량을 정량적으로 추정하기 위한 작업의 하나로 이루어졌다. 실험방법은 삼척소재 소나무를 대상으로 영급별로 생엽과 굵기 10mm이하의 가지를 채취하여 콘칼로리미터와 NDIR분석기로 연소 시 배출되는 CO2, CO, NO, CH4, N2O의 배출량을 분석하였다. 실험조건은 10cm×10cm×5cm의 방형틀을 채우는 생엽과 가지부분을 건조기에 건조하여 더 이상 중량변화가 없을 때까지 실험하여 얻은 값을 사용하였으며, 결과값은 3회 측정한 평균값이다.
        643.
        2012.01 KCI 등재 서비스 종료(열람 제한)
        The rate of photosynthesis (A) of leaves from 10 plant species (6 evergreen and 4 deciduous) of the family Fagaceae was measured using a portable photosynthesis analyzer, to examine which species take up CO2 most efficiently. Of the evergreen species, the photosynthetic rate of Castanopsis cuspidata var. sieboldii was highest, and remained above 82.1~106.4 μmol kg-1s-1 from July to November. Of the deciduous species, the photosynthetic rate of Quercus acutissima was higher than that of the other three species, and remained high at 83.5~116.6 μmol kg-1s-1 from September to November. The photosynthetic rate of the 10 species was positively correlated with stomatal conductance (gs) and transpiration rate (E). However, there was no correlation between photosynthetic rate and intercellular CO2 concentration (Ci), although there was a positive correlation just in three species (Q. gilva, Q. acutissima and Q. glauca). These results suggest that the CO2 fixation capacity of C. cuspidata var. sieboldii, an evergreen species, and Q. acutissima, a deciduous species, is significantly higher than that of the other species examined, and that photosynthesis is regulated by both stomatal conductance and transpiration. Therefore, C. cuspidata var. sieboldii and Q. acutissima may be valuable for the evaluation of carbon uptake in urban green spaces as well as in afforested areas.
        652.
        2011.09 KCI 등재 서비스 종료(열람 제한)
        Projected increases in atmospheric CO2 concentration ([CO2 ]) and temperature (Ta ) have the potential to alter in rice growth and yield. However, little is known about whether Ta warming with elevated [CO2 ] modify plant architecture. To better understand the vertical profiles of leaf area index (LAI) and the flag leaf morphology of rice grown under elevated Ta and [CO2 ], we conducted a temperature gradient field chamber (TGC) experiment at Gwangju, Korea. Rice (Oryza sativa L. cv. Dongjin1ho) was grown at two [CO2 ] [386 (ambient) vs 592 ppmV (elevated)] and three Ta regimes [26.8 (~approx ambient), 28.1 and 29.8~circC ] in six independent field TGCs. While elevated Ta did not alter total LAI, elevated [CO2 ] tended to reduce (c. 6.6%) the LAI. At a given canopy layer, the LAI was affected neither by elevated [CO2 ] nor by elevated Ta , allocating the largest LAI in the middle part of the canopy. However, the fraction of LAI distributed in a higher and in a lower layer was strongly affected by elevated Ta ; on average, the LAI distributed in the 75-90 cm (and 45-60 cm) layer of total LAI was 9.4% (and 35.0%), 18.8% (25.9%) and 18.6% (29.2%) in ambient Ta , 1.3~circC and 3.0~circC above ambient Ta , respectively. Most of the parameters related to flag leaf morphology was negated with elevated [CO2 ]; there were about 12%, 5%, 7.5%, 15% and 21% decreases in length (L), width (W), L:W ratio, area and mass of the flag leaf, respectively, at elevated [CO2 ]. However, the negative effect of elevated [CO2 ] was offset to some extent by Ta warming. All modifications observed were directly or indirectly associated with either stimulated leaf expansion or crop phenology under Ta warming with elevated [CO2 ]. We conclude that plant architecture and flag leaf morphology of rice can be modified both by Ta warming and elevated [CO2 ] via altering crop phenology and the extent of leaf expansion.
        653.
        2011.08 KCI 등재 서비스 종료(열람 제한)
        For this research, they were monitored CO2 flux and environmental factors (CO2 concentration, soil temperature, soil moisture, soil organic carbon, soil pH, soil Eh) in foreshore, paddy field and woods sites at the winter season (January 2009) and the summer season (September 2009). Seasonal and spatial variations for monitored data were analyzed, and linear regression functions of CO2 flux as environmental factors were estimated. CO2 fluxes averaged between surface and atmosphere monitored in foreshore and paddy field at the winter season were shown -8 mgCO2m-2hr-1 and -25 mgCO2m-2hr-1, respectively. CO2 fluxes averaged between surface and atmosphere monitored in foreshore and paddy field at the summer season were shown 47 mgCO2m-2hr-1 and 117 mgCO2m-2hr-1, respectively. Thus, CO2 was sunk from atmosphere to surface at the winter season and it was emitted from surface to atmosphere at the summer season. CO2 fluxes in woods site were emitted 145 mgCO2m-2hr-1 at the winter season and 279 mgCO2m-2hr-1 at the summer season.
        654.
        2011.07 KCI 등재 서비스 종료(열람 제한)
        Adsorption experiment of carbon dioxide was performed on MCM41 silica impregnated with two kinds of EDA(ethylenediamine) and MEA(monoethanolamine). The prepared adsorbents were characterized by BET surface area, X-ray diffraction and FT-IR. The CO2 capture study was investigated in a U type packed column with GC/TCD. The results of XRD for MCM-41 and amine-impregnated MCM41 showed typical the hexagonal pore system. BET results showed the MCM 41 impregnated amine to have a surface area of 141 m2/g to 595 m2/g and FT-IR revealed a N-H functional group at about 1400cm-1 to 1600cm-1. The CO2 adsorption capacity on EDA and MEA was as follow: MCM41-EDA30 > MCM41 -EDA40 >MCM41-EDA20 >MCM-EDA10 and MCM41-MEA40 >MCM41-MEA30 > MCM41-MEA20> MCM41-MEA10. The MCM41-EDA30 showed the highest adsorption capacity due to physical adsorption and chemical adsorption by amino-group content. The results suggest that mesoporous media with EDA is effective adsorbent for CO2 capture from flue gases.
        655.
        2010.12 KCI 등재 서비스 종료(열람 제한)
        The adsorption characteristics of CO2 gas on impregnated activated carbons with MEA (Mono-ethanolamine) and AMP (2-Amino 2-methyl 1-propanol) were studied to improve the adsorption ability of CO2 gas on activated carbon. The equilibrium adsorption capacity of CO2 gas was increased by increment of impregnation concentration up to 40 %, but decreased above 50 %. The adsorption capacity of activated carbon impregnated with AMP was higher than activated carbon impregnated with MEA. The breakthrough was fast according to increment of inlet concentration of CO2 gas.
        658.
        2010.06 KCI 등재 서비스 종료(열람 제한)
        The study was conducted to investigate the effects of organic fertilizers and mulches on the growth and CO₂ assimilation in MM.106 apple trees. Growth and CO₂ assimilation of MM.106 apple trees grown in a greenhouse were affected by the nutrient concentrations and carbon (C) and nitrogen (N) ratio in the raw materials of organic fertilizers and mulches. The optimum C:N ratios, which makes microorganism convert the organic N into the inorganic N, were obtained in the organic fertilizer, poultry litter, green compost, and grass clippings, resulting in increasing single shoot height, SPAD, and CO₂ assimilation. The SPAD and CO₂ assimilation were affected by the treatments 5 weeks after the treatments, and then the tree growth was affected by the treatments 6 weeks later. The most efficient tree growth and development were observed in the 10 to 15 ㎎ㆍ㎏⁻¹ of the inorganic N in a soil, and the N was strongly related to the tree growth and development.