• Title/Summary/Keyword: carbon balance

검색결과 267건 처리시간 0.019초

Method for Assessing Forest Carbon Sinks by Ecological Process-Based Approach - A Case Study for Takayama Station, Japan

  • Lee, Mi-Sun
    • The Korean Journal of Ecology
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    • 제26권5호
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    • pp.289-296
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    • 2003
  • The ecological process-based approach provides a detailed assessment of belowground compartment as one of the major compartment of carbon balance. Carbon net balance (NEP: net ecosystem production) in forest ecosystems by ecological process-based approach is determined by the balance between net primary production (NPP) of vegetation and heterotrophic respiration (HR) of soil (NEP=NPP-HR). Respiration due to soil heterotrophs is the difference between total soil respiration (SR) and root respiration (RR) (HR=SR-RR, NEP=NPP-(SR-RR)). If NEP is positive, it is a sink of carbon. This study assessed the forest carbon balance by ecological process-based approach included belowground compartment intensively. The case study in the Takayama Station, cool-temperate deciduous broad-leaved forest was reported. From the result, NEP was estimated approximately 1.2 t C $ha^{-1} yr^{-1}$ in 1996. Therefore, the study area as a whole was estimated to act as a sink of carbon. According to flux tower result, the net uptake rate of carbon was 1.1 t C $ha^{-1} yr^{-1}$.

Energy Balance by Carbon and Nitrogen Balance Technique in White Leghorn and Rhode Island Red Hens Fed Maize- and Broken Rice-Based Diets

  • Jadhao, S.B.;Tiwari, C.M.;Chandramoni, Chandramoni;Khan, M.Y.
    • Asian-Australasian Journal of Animal Sciences
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    • 제12권7호
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    • pp.1080-1084
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    • 1999
  • Carbon (C) and nitrogen (N) balance technique was used to determine energy balance in Rhode Island Red (RIR) and White Leghorn (WL) laying hens fed maize-and broken rice (BR)- based diets. Carbon and nitrogen intake and outgo were determined for three days on ad libitum fed diets followed by 2/3 of ad libitum intake for next three days. Carbon analysis was done by using four 'U' tubes in which carbon dioxide released during bomb calorimetry was absorbed on drierite in tube 1 and 2 whereas tube 3 and 4 contained sodalime self indicating granule. Carbon in $CO_2$ was determined by an open circuit respiration system. Energy retention (E, kcal) was calculated as E = 12.386 C (g) - 4.631 N (g). By regressing metabolisable energy (ME) intake on energy balance, maintenance ME requirement of RIR was 128 whereas, that of WL hens was $144kcal/kg\;W^{0.75}/d$. Effciency of utilization of ME for maintenance from BR-based diet in RIR hens was equal but in WL hens it was 11% less than maize-based diet.

건축 및 토목 구조물의 CO2 수지 평가에 관한 연구 (A Study on the CO2 Balance Evaluation of Building and Civil Engineering Structures)

  • 조형규;송훈;이한승
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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    • pp.121-122
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    • 2011
  • Globally about 40% of total carbon dioxide emissions occupies from the construction industry. Therefore, it is important to quantitatively calculate carbon dioxide emission of concrete prior to the reduction of carbon dioxide. ddd In addition, it is also important to quantitatively calculate carbon dioxide absorption of concrete because concrete absorbs in a measure of carbon dioxide. In this study, it carried out carbon dioxide balance evaluation of building and civil engineering structures through carbon dioxide balance evaluation method of concrete. Consequently absorption rate compared with carbon dioxide emission is about 2.5~5.18%.

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ALKANE의 微生物酸化의 反應條件과 炭素 및 窒素平衡 (Reaction Conditions and Carbon, Nitrogen Balance in the Course of Microbiological Oxidation of Alkane)

  • 박태원
    • 대한화학회지
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    • 제13권2호
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    • pp.187-193
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    • 1969
  • As part of an extensive program on the microbiological oxidation of hydrocarbons, reaction conditions and nutrients consumption of candida lipolytica grown on alkane as carbon source were studied. For optimum growth of yeast, the conditions of pH 5, temperature $30^{\circ}C$, carbon number $C_{16}$& $C_{18}$aeration 25.6 1/l/hr, agitation 3000 r.p.m., hydrocarbon concentration 10% were obtained. Carbon and nitrogen balance related to these conditions were also investigated. In the course of this investigation, some significant effects of pH and carbon number of hydrocarbon variation were observed.

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Estimation of Landfill Stabilization using Carbon-based Mass Balance Evaluation

  • Chun, Seung-Kyu
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제21권2호
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    • pp.22-28
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    • 2016
  • In order to evaluate landfill stabilization based on organic carbon, stoichiometric analysis and a biological methane potential (BMP) test based on modeling were performed at the 2nd Sudokwon Landfill Site. Mass balance analysis through a BMP test proved to be more adaptable for evaluation, and it showed that 28.9% of landfill organic carbon was expected to remain by 2046, 30 years after landfill closure. The organic carbon ratio of total landfill waste for 2046 is forecasted as 2.9% in demolition waste and 5.1% in household waste, and, if one were to consider plastic as an organic waste, the ratios would increase to 15.9% and 28.3%, respectively. Therefore, it seems that organic matter biodegradation facilitating measures such as bioreactor landfill technology and preemptive recovery of combustible waste are necessary to shorten post closure management periods and to meet the landfill stabilization guidelines more safely.

연료 조성에 따른 공연비 산정 (III) - 공연비 계산방식간의 상호 비교 - (Air Fuel Ratio and Calculation According to Fuel Composition (III) -Comparison of Various Calculation Method-)

  • 박찬준;엄인용
    • 대한기계학회논문집B
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    • 제28권10호
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    • pp.1147-1154
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    • 2004
  • This paper is the third of several companion papers which compare the method of Air-Fuel ratio determination. In the previous works, Eltinge chart was expanded to arbitrary fuel composition as a reference exhaust composition. The compensation of unburned hydrocarbon in Eltinge chart and comparison of Spindt and Eltinge method were also discussed. In addition to Eltinge and Spindt's one, however, there are many methods which calculate Air-Fuel ratio from exhaust emission. Among these methods, carbon balance and oxygen balance are widely used in practice. In some applications, linear formula from statistical method is being used in the field due to its simplicity and convenience. In this paper, these various methods are evaluated and compared with Eltinge results and new linear formula is proposed for the gasoline fuel. The results show that the corrected carbon balance equation has excellent agreement with Eltinge and Spindt's one. On the other hands, the oxygen-balanced formula has a limitation according to the mixture state and AFR. For gasoline fuel, newly proposed linear equation has good compatibility with Eltinge and Spindt up to AFR 17.

녹색기업의 사업활동 전 과정에 대한 환경성 평가 -2. 물질수지 및 환경개선 (Life Cycle Assessment for the Business Activities of Green Company -2. Mass Balance and Environmental Improvement)

  • 신춘환;박도현
    • 한국환경과학회지
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    • 제22권4호
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    • pp.425-433
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    • 2013
  • A mass balance of process was calculated by using the analysis of basic unit and environmental assessment of all the processes of Busan fashion color industry cooperative that operates a combined heat and power plant and a bio treatment plant. The mass balance for the combined heat and power plant was done, based on boiler and water treatment processes while each unit reactor was used for the bio treatment plant. From the results above, a resource recycle network, a treatment flowchart for food waste water/wastewater treatment and a carbon reduction program were established.

Wave propagation in spherical and cylindrical panels reinforced with carbon nanotubes

  • Yi-Wen Zhang;Hao-Xuan Ding;Gui-Lin She
    • Steel and Composite Structures
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    • 제46권1호
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    • pp.133-141
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    • 2023
  • Based on the third-order shear deformation theory, the wave propagations in doubly curved spherical- and cylindrical- panels reinforced by carbon nanotubes (CNTs) are firstly investigated in present work. The coupled equations of wave propagation for the carbon nanotubes reinforced composite (CNTRC) doubly curved panels are established. Then, combined with the harmonic balance method, the eigenvalue technique is adopted to simulate the velocity-wave number curves of the CNTRC doubly curved panels. In the end, numerical results are showed to discuss the effects of the impact of key parameters including the volume fraction, different shell types (including spherical (R1=R2=R) and cylindrical (R1=R, R2=→∞)), wave number as well as modal number on the sensitivity of elastic waves propagating in CNTRC doubly curved shells.

무기탄소 순환에 대한 소규모 호수 유역의 반응 (The Responses of a Small Lake Watershed to an Inorganic Carbon Cycle)

  • 조영일
    • 한국물환경학회지
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    • 제29권5호
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    • pp.610-617
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    • 2013
  • Investigating the budgets of alkalinity and dissolved inorganic carbon (DIC) in lake water systems is significant for the examination of the behavior of a lake as a sink or a source with respect to the circulation of inorganic carbon chemistry. Budgets of total alkalinity ($Alk_T$) and DIC in Onondaga Lake, which was polluted by chronic calcium (Ca) loading in spite of the closure of soda ash ($Na_2CO_3$) facility, were determined by the analyses of inorganic carbon chemistry in tributary stream channels linked to the lake. AlkT and DIC fluxes of Onondaga Creek and Ninemile Creek occupied 65% and 54%, respectively, as larger tributary streams in comparison with other tributaries as well as different input sources. Budget calculations indicate that 18% of AlkT and 11% of DIC inputs to Onondaga Lake, respectively, remained immobilized in the Lake. This suggests that Ca chronically leached had been precipitated with inorganic carbon or remineralized by secondary mineral formation during the experimental period. In this study, the assumed mass balance calculation in Onondaga Lake with tributary streams resulted in exhibiting that the lake played a role of the sink for the inorganic carbon cycle.

Carbon balance and net ecosystem production in Quercus glauca forest, Jeju Island in South Korea

  • Jeong, Heon Mo;You, Young Han;Hong, Seungbum
    • Journal of Ecology and Environment
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    • 제46권3호
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    • pp.250-258
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    • 2022
  • Background: To assess the carbon sequestration capacity and net ecosystem productivity (NEP) of Quercus glauca forests, we analyzed the net primary productivity (NPP), carbon storage, and carbon emission of soil in a Q. glauca forest on Jeju Island (South Korea) from 2016 to 2018. Results: The average carbon stock in the above- and below-ground plant biomass was 223.7 Mg C ha-1, while the average amount of organic carbon fixed by photosynthesis was 9.8 Mg C ha-1 yr-1, and the average NPP was 9.6 Mg C ha-1 yr-1. Stems and branches contributed to the majority of the above- and below-ground standing biomass and NPP. The average heterotrophic carbon emission from the soil was 8.7 Mg C ha-1 yr-1, while the average NEP was 1.1 Mg C ha-1 yr-1. Although the carbon stock, carbon absorption, and soil respiration values were higher than those reported in other oak forests in the world, the NEP was similar or lower. Conclusions: These results indicator that Q. glauca forests perform the role of a large carbon sink through the CO2 absorption in the plants in terms of carbon balance. And it is judged to be helpful as data for assessment of carbon storage and flux in the forests and mitigation of elevated CO2 in the atmosphere.