• 한국환경과학회지
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• 제23권6호
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• pp.1003-1012
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• 2014

We examined the combined impacts of future increases of $CO_2$ and temperature on the growth of four marine diatoms (Skeletonema costatum, Chaetoceros debilis, Chaetoceros didymus, Thalassiosira nordenskioeldii). The four strains were incubated under four different conditions: present ($pCO_2$: 400ppm, temperature: $20^{\circ}C$), acidification ($pCO_2$: 1000ppm, temperature: $20^{\circ}C$), global warming ($pCO_2$: 400ppm, temperature: $25^{\circ}C$), and greenhouse ($pCO_2$: 1000ppm, temperature: $25^{\circ}C$) conditions. Under the condition of higher temperatures, growth of S. costatum was suppressed, while C. debilis showed enhanced growth. Both C. didymus and T. nodenskioldii showed similar growth rates under current and elevated temperature. None of the four species appeared affected in their cell growth by elevated $CO_2$ concentrations. Chetoceros spp. showed increase of pH per unit fluorescence under elevated $CO_2$ concentrations, but no difference in pH from that under current conditions was observed for either S. costatum or T. nodenskioeldii, implying that Chetoceros spp. can take up more $CO_2$ per cell than the other two diatoms. Our results of cell growth and pH change per unit fluorescence suggest that both C. debilis and C. didymus are better adapted to future oceanic conditions of rising water temperature and $CO_2$ than are S. costatum and T. nodenskioeldii.

• 한국환경과학회지
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• 제26권5호
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• pp.601-608
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• 2017

The effects of elevated atmospheric $CO_2$ on growth and photosynthesis of soybean (Glycine max Merr.) were investigated to predict its productivity under elevated $CO_2$ levels in the future. Soybean grown for 6 weeks showed significant increase in vegetative growth, based on plant height, leaf characteristics (area, length, and width), and the SPAD-502 chlorophyll meter value (SPAD value) under elevated $CO_2$ conditions ($800{\mu}mol/mol$) compared to ambient $CO_2$ conditions ($400{\mu}mol/mol$). Under elevated $CO_2$ conditions, the photosynthetic rate (A) increased although photosystem II (PS II) photochemical activity ($F_v/F_m$) decreased. The maximum photosynthetic rate ($A_{max}$) was higher under elevated $CO_2$ conditions than under ambient $CO_2$ conditions, whereas the maximum electron transport rate ($J_{max}$) was lower under elevated $CO_2$ conditions compared to ambient $CO_2$ conditions. The optimal temperature for photosynthesis shifted significantly by approximately $3^{\circ}C$ under the elevated $CO_2$ conditions. With the increase in temperature, the photosynthetic rate increased below the optimal temperature (approximately $30^{\circ}C$) and decreased above the optimal temperature, whereas the dark respiration rate ($R_d$) increased continuously regardless of the optimal temperature. The difference in photosynthetic rate between ambient and elevated $CO_2$ conditions was greatest near the optimal temperature. These results indicate that future increases in $CO_2$ will increase productivity by increasing the photosynthetic rate, although it may cause damage to the PS II reaction center as suggested by decreases in $F_v/F_m$, in soybean.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.168-168
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• 2022

According to the 5th Climate Change Report, global average temperature in 2081~2100 will increase 1.8℃ based on RCP 4.5 and 3.7℃ based on RCP 8.5 from the current climate value (IPCC Working Group I AR5). As temperature is expected to increase due to global warming and the intensity and frequency of rainfall are expected to increase, damage to crops is expected, and countermeasures must be taken. This study intends to evaluate rice growth in terms of nitrogen utilization efficiency according to future climate change conditions. In this experiment, Oryza sativa cv. Shindongjin were planted at the SPAR facility of the NICS in Wanju-gun, Jeollabuk-do on June 10, and were planted and grown according to the standard cultivation method. Cultivation conditions are high temperature, high CO₂ (current temperature+4.7℃·CO₂ 800ppm), high temperature (current temperature+4.7℃·CO₂ 400ppm), current climate (current tempreture·CO₂ 400 ppm). Nitrogen was varied as 0, 9, 18 kg/10a. The N content and C/N ratio of all rice leaves, stems, and seeds increased at high temperature, and the N content and C/N ratio decreased under high temperature and high CO₂ conditions com pared to high temperature. Compared to the current climate, NUE increases by about 8% under high temperature and high CO₂ conditions and by about 2% under high temperature conditions. This seems to be because the increase in temperature and CO₂ induced the increase in biomass. ANUE related to yield decreased by about 70% compared to the current climate under high temperature conditions, and decreased by about 45% at high temperature and high CO₂, showing a tendency to decrease compared to high temperature. This appears to be due to reduced fertility and poor ripening due to high temperature stress. However, as the nitrogen increased, the number of ears and the number of grains increased, slightly offsetting the production reduction factor.

• 한국농림기상학회지
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• 제24권4호
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• pp.275-284
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• 2022

기후변화에 따른 대기 온도 및 이산화탄소 농도의 상승은 농업 생산성에 큰 영향을 미칠 것으로 예상된다. RCP 8.5 시나리오에 따른 21세기말(2071~2100) 기후조건에서는 전 생육기간에 걸쳐 군락광합성이 크게 증가하였으나 이러한 효과가 종실 수량 증가로는 이어지지 않았다. 특히 높은 광합성능으로 인한 바이오매스의 증가는 분지 수 확보에 긍정적으로 작용하여 협수와 립수는 큰 변동이 없었던 반면 립중은 단독 고온 조건과 유사하게 현저히 감소하였다. 이는 등숙기간 중 고온에 의한 동화산물의 축적 및 전류 불량이 주요 요인으로 판단된다. 이러한 결과는 미래 기후 환경에서 종실 수량 감소가 협수와 립수 보다는 립중의 감소에 의한 것임을 의미한다. 이와 같은 결과들은 우리나라 남부지역에서 기후변화에 따른 콩 생육의 불확실성을 해소하고 피해 대책을 마련하기 위한 기초자료로써 유용하게 활용될 것으로 기대된다.

• 한국작물학회지
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• 제63권2호
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• pp.164-173
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• 2018

본 연구는 옥외환경조절 시설인 SPAR챔버에서 향후 기후변화가 지속 될 경우 상승된 이산화탄소와 온도 그리고 한발에 따른 감자의 군락 형태와 무기영양 변화에 대한 결과는 다음과 같다. 1. AT+2.8C700는 상승된 $CO_2$와 고온에 의하여 초장과 엽면적 그리고 건물중이 상당히 증가 하였고, AT+2.8C700DS는 한발의 영향으로 상당히 감소하였다. 2. 수확기에서 잎은 AT+2.8C700은 ATC450에 비하여 질소와 인산이 감소한 반면 칼륨, 칼슘 그리고 마그네슘 농도가 증가하였다. 괴경은 질소, 인산 그리고 칼륨이 감소하였으며, 칼슘과 마그네슘은 변화가 없었다. 반면, AT+2.8C700DS는 한발의 영향으로 무기영양 농도가 상대적으로 다른 처리비하여 낮았지만, 마그네슘 농도만 증가하였다. 3. $CO_2$와 온도 상승을 보면 AT+2.8C700는 ATC450에 비하여 질소 농도의 감소로 26% 단백질 함량이 감소를 하였다. 한발을 받은 AT+2.8C700DS보다 AT+2.8C700는 단백질 함량이 20%가 감소 하였다. 4. 따라서 상승된 $CO_2$ 농도와 한발은 무기영양의 변화뿐만 아니라 광합성 관련된 당과 아미노산 같은 2차 대사물질도 변화와 인간의 단백질 섭취에도 영향을 줄 것이다.

• 대기
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• 제25권1호
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• pp.85-97
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• 2015

This study is to investigate future changes in carbon cycle using the HadGEM2-Carbon Cycle simulations driven by $CO_2$ emissions. For experiment, global carbon budget is integrated from the two (8.5/2.6) representative concentration pathways (RCPs) for the period of 1860~2100 by Hadley Centre Global Environmental Model, version 2, Carbon Cycle (Had-GEM2-CC). From 1985 to 2005, total cumulative $CO_2$ amount of anthropogenic emission prescribed as 156 GtC. The amount matches to the observed estimates (CDIAC) over the same period (136 GtC). As $CO_2$ emissions into the atmosphere increase, the similar increasing tendency is found in the simulated atmospheric $CO_2$ concentration and temperature. Atmospheric $CO_2$ concentration in the simulation is projected to be 430 ppm for RCP 2.6 at the end of the twenty-first century and as high as 931 ppm for RCP 8.5. Simulated global mean temperature is expected to rise by $1.6^{\circ}C$ and $3.5^{\circ}C$ for RCP 2.6 and 8.5, respectively. Land and ocean carbon uptakes also increase in proportion to the $CO_2$ emissions of RCPs. The fractions of the amount of $CO_2$ stored in atmosphere, land, and ocean are different in RCP 8.5 and 2.6. Further study is needed for reducing the simulation uncertainty based on multiple model simulations.

• 한국농공학회논문집
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• 제56권2호
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• pp.47-57
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• 2014

This study was conducted to predict greenhouse gas (GHG) emission from paddy by future climate change scenario in Korea. Chuncheon city in Kangwon province were selected as study area. A1B Special Report on Emission Scenario (SRES) of the IPCC (Intergovernmental panel on climate change) was used to assess the future potential climate change. The rainfall and temperature was projected to increase by 8.4 % and 1.9 % (2040s), 35.9 % and 27.0 % (2060s), 19.2 % and 30.8 % (2090s), respectively, compare to the 2010s value. Under the climate change, Denitrification-Decomposition (DNDC) predicted an increase in $N_2O$, $CO_2$ and $CH_4$ emissions from paddy. The simulations resulted in annual net emissions of 0.4~2.4, 500.5~734.5 and 29.4~160.4 kg/ha/year of $N_2O-N$, $CH_4-C$ and $CO_2-C$, respectively, with a cumulated global warming potential (GWP) of $14.5{\sim}21.7t{\cdot}CO_2/ha/year$ were affected by rainfall, temperature, manure amendment and fertilizer amount. The simulation results suggested that implementation of manure amendment or reduction of water consumption instead of increased fertilizer application rates would more efficiently mitigate GHG emissions.

• 한국분무공학회지
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• 제29권2호
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• pp.68-74
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• 2024

As awareness of environmental pollution problems increases worldwide, interest in air pollutants is increasing. In particular, NOx and PM, which are major pollutants in diesel vehicles, are contributing significantly to emissions. As a result, its importance is increasing. In this study, based on research results applied to large diesel vehicles, the problem of natural regeneration caused by low exhaust gas temperature during low speed and low load operation is solved by applying a complex regeneration DPF that is not affected by temperature conditions to small diesel vehicles. The feasibility of application to small diesel vehicles was reviewed by measuring the emission reduction efficiency. As a result of the engine test, the power reduction rate and fuel consumption rate before and after device installation under full load conditions were 2.9% decrease and 3.5% increase, respectively, satisfying the standard for a 5% reduction, and as a result of the regeneration equilibrium temperature (BPT) test, the regeneration temperature was 310℃. appeared at the level. The reduction efficiency test results for the actual vehicle durability test equipment showed 97.3% PM, 51.0% CO, and 31.1% HC, while the city commuter vehicle had PM 97.5%, CO 61.7%, HC 40.0%, and the school bus vehicle had PM 96.8%, CO 44.4%, HC 34.3%, and low-speed logistics vehicles showed a reduction efficiency of 98.2% for PM, 36.0% for CO, and 45.7% for HC. Based on the results of this study, in the future, it is necessary to secure DPF technology suitable for all vehicle types through actual vehicle application research on temperature condition-insensitive composite regenerative DPF for medium-sized vehicles.

• 한국기후변화학회지
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• 제7권4호
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• pp.433-442
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• 2016

In this study, we examine future changes in surface radiation associated with cloud amount and aerosol emission over East Asia. Data in this study is HadGEM2-CC (Hadley Centre Global Environmental Model version 2, Carbon Cycle) simulations of the Representative Concentration Pathways (RCPs) 2.6/4.5/8.5. Results show that temperature and precipitation increase with rising of the atmosphere $CO_2$. At the end of $21^{st}$ century (2070~2099) relative to the end of $20^{st}$ century (1981~2005), changes in temperature and precipitation rate are expected to increase by $+1.85^{\circ}C/+6.6%$ for RCP2.6, $+3.09^{\circ}C/+8.5%$ for RCP4.5, $+5.49^{\circ}C/10%$ for RCP8.5. The warming results from increasing Net Down Surface Long Wave Radiation Flux (LW) and Net Down Surface Short Wave Radiation Flux (SW) as well. SW change increases mainly from reduced total Aerosol Optical Depth (AOD) and low-level cloud amount. LW change is associated with increasing of atmospheric $CO_2$ and total cloud amount, since increasing cloud amounts are related to absorb LW radiation and remit the energy toward the surface. The enhancement of precipitation is attributed by increasing of high-level cloud amount. Such climate conditions are favorable for vegetation growth and extension. Expansion of C3 grass and shrub is distinct over East Asia, inducing large latent heat flux increment.

• 한국습지학회지
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• 제16권1호
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• pp.11-18
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• 2014

증가된 이산화탄소 농도와 온도상승에 따른 멸종위기 수생식물 독미나리의 생태학적 반응을 알아보기 위해 대조구, 온도상승구, 그리고 $CO_2$+온도상승구에서 생육시킨 결과를 비교하였다. 독미나리의 지상부 길이는 대조구, 온도상승구 그리고 $CO_2$+온도상승구간에 차이가 없었지만, 분얼 수는 대조구, 온도상승구, $CO_2$+온도상승구 순으로 증가했다. 복산형화서의 수는 대조구와 온도상승구에서 같았고, $CO_2$+온도상승구에서 감소했다. 소산형화서의 수는 대조구와 온도상승구, $CO_2$+온도상승구간에 차이가 없었다. 종자형성률은 온도상승구와 $CO_2$+온도상승구가 대조구보다 감소했고, 온도상승구와 $CO_2$+온도상승구간에 차이가 없었다. 이상으로 보면, $CO_2$농도와 온도상승은 길이생장에 영향을 주지 않은 반면, 분얼 수는 증가시키고 종자생산은 감소시킨다. 그러므로 독미나리는 지구 온난화 조건이 되면 종자생산보다 분얼을 늘려 무성번식 경향이 증가될 것이며, 이러한 개체군 생장을 연구하는 것은 멸종위기종 연구에 중요한 자료로 활용될 것이다.