• Weed & Turfgrass Science
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• 제2권4호
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• pp.381-386
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• 2013

지구온난화로 인한 기후변화로 인하여 강수량과 집중강우의 빈도가 높아질 것으로 예측된다. 본 연구는 잔디류와 기타 식량 원예작물 들의 토양유실을 알아보고자 수행하였다. 작물별 토양유실은 한국잔디와 한지형잔디 처리구의 강수량 및 강우 강도와 상관없이 토양유실이 거의 발생하지 않아서 토양침식에 대한 보호 효과가 매우 우수하였다. 작물별 연간 토양 침식 총량은 한국잔디로 전면 피복된 곳이 가장 적었으며, 그다음 줄떼로 조성된 한국잔디와 한지형잔디로 피복된 실험구에서 토양침식이 매우 적었다. 그리고 밭벼와 콩 재배구에서 5~10 $MT{\cdot}ha^{-1}{\cdot}yr^{-1}$, 고추 재배구에서 7~14 $MT{\cdot}ha^{-1}{\cdot}yr^{-1}$의 토양침식량이 발생되었다. 잡초가 방치된 실험구의 토양침식이 크게 감소된 것에 반하여 잡초가 제거된 나지의 연간 토양침식 총량은 18 $MT{\cdot}ha^{-1}{\cdot}yr^{-1}$이상 크게 발생되었다.

• Fisheries and Aquatic Sciences
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• 제17권3호
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• pp.345-353
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• 2014

Copper has been widely used to control algae and pathogens in fish culture ponds. However, its toxic effects on fish depend not only on its concentration in the water but also on the water quality. A laboratory experiment was conducted to assess copper toxicity in the black rockfish Sebastes schlegeli using a panel of antioxidant enzymes, including glutathione (GSH), glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR) and superoxide dismutase (SOD), at different levels of copper at three water temperatures (WT, 18, 23, $28^{\circ}C$) for 4 days. After exposure to two copper concentrations (100 and $200{\mu}g/L$), GSH levels and GST activities increased significantly, depending on WT (P < 0.05) in the liver, gill, and kidney of the black rockfish. GPx and SOD activities decreased significantly with both increasing WT and copper treatment in the organs of black rockfish (P < 0.05). These changes can be seen as initial responses to temperature stress and as a sustained response to copper exposure. This also indicates that GSH and related enzymes activities were sensitive indexes to stress by toxicants such as copper. The present findings suggest that simultaneous stress due to temperature change and copper exposure can accelerate changes in enzymes activities in the black rockfish. This provides another example of synergism between environmental temperature and pollutants, which may have important implications for the survival of fish in polluted environments during seasonal warming and/or global climate change.

• 한국환경농학회지
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• 제27권4호
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• pp.406-412
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• 2008

Biogas plant with anaerobic digestion is receiving high attention as a facility for both livestock waste treatment and electric power generation. Objective of this study was to perform life cycle assessment (LCA) of a biogas plant which incorporates swine and food waste (7:3) as source materials for biogas production. In addition, the biogas production process was compared with the prevalent composting method as a reference in the aspects of green house gas (GHG) reduction potential and environmental impact. The biogas method was capable of reducing 52 kg $CO_2$ eq. emission per ton of swine/food waste, but the composting process was estimated to emit 268 kg $CO_2$ eq. into air. The biogas method was evaluated as more beneficial to the environment by mitigating the impact on abiotic depletion potential (ADP), global warming potential (GWP), ozone depletion potential (ODP), eutrophication potential (EP), and photochemical ozone creation potential (POCP), but not to acidification potential (AP).

• 한국작물학회:학술대회논문집
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• 한국작물학회 2019년도 추계학술대회
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• pp.19-19
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• 2019

It is necessary to maintain stable crop productions under the unsuitable environments, because the drought and flood may be frequently caused by the global warming. Therefore, it is agent to improve the crop growth model corresponded to soil moisture status. Chili pepper (Capsicum annuum) is one of the useful crop in Asia, and then it is affected by change of precipitation in consequence drought and flood occur however crop model to evaluate water stresses on chili pepper is not enough yet. In this study, development of crop model under different soil moisture status was attempted. The experiment was conducted on the slope fields in the greenhouse. The water level was kept at 20cm above the bottom of the container. Habanero (C. chinense) was used as material for crop model. Sap bleeding rate, SPAD value, chlorophyll content, stomatal conductance, leaf water potential, plant height, leaf area and shoot dry weight were measured at 10 days after treatment (DAT) and 13 DAT. Moreover, temperature and RH in the greenhouse, soil volume water contents (VWC) and soil water potential were measured. As a result, VWC showed 4.0% at the driest plot and 31.4% at the wettest plot at 13 DAT. The growth model was calculated using WVC and the growth analysis parameters. It was considered available, because its coefficient of determination showed 0.84 and there are significant relationship based on plants physiology among the parameters and the changes over time. Furthermore, we analyzed the important factors for higher accuracy prediction using multiple regression analysis.

• Parasites, Hosts and Diseases
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• 제56권6호
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• pp.559-565
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• 2018

The identification and characterization of pathogenic and zoonotic tick-borne diseases like granulocytic anaplasmosis are essential for developing effective control programs. The differential diagnosis of pathogenic Anaplasma phagocytophilum and non-pathogenic A. phagocytophilum-like Anaplasma spp. is important for implementing effective treatment from control programs. The objective of the present study was to investigate the prevalence of Anaplasma spp. in horses in Korea by nucleotide sequencing and restriction enzyme fragment length polymorphism assay. Of the 627 horses included in the study, only 1 (0.2%) was infected with A. phagocytophilum. Co-infection with A. phagocytophilumlike Anaplasma spp. was not detected in the study. The 16S rRNA sequence of A. phagocytophilum was similar (99.5-100%) to A. phagocytophilum 16S rRNA isolated from horses in other countries. PCR adapted to amplify A. phagocytophilum groEL and msp2 genes failed to generate amplicons, suggesting genetic diversity in these genes. This study is the first molecular detection of A. phagocytophilum in horses in Korea. Human granulocytic anaplasmosis and animal infection of A. phagocytophilum have been reported in Korea recently. Because of vector tick distribution, global warming, and the increase of the horse industry, horses should be considered as a potential reservoir for A. phagocytophilum, and cross infectivity should be evaluated even though a low prevalence of infection was detected in this study. Furthermore, continuous surveillance and effective control measures for A. phagocytophilum should be established to prevent disease distribution and possible transmission to humans.

• 한국포장학회지
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• 제27권3호
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• pp.169-174
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• 2021

우리나라가 1인당 플라스틱 년간 소비량이 132 kg(2019)으로 세계1위로 나타났고, 지구온난화와 탄소중립을 위한 국제적 협약이 진해되고 있으며 소비자들도 바이오플라스틱에 대한 관심과 니즈가 증가하고 있어, 바이오플라스틱 소재에 복합 사용화 첨가제를 농도별로 첨가하여 필름을 생산 시 토출량, 용융지수, 인장강도 변화를 조사하였다. 석유계 수지인 LLDPE와 LDPE보다 PLA와 PBAT에서 용융지수가 현저히 높은 것으로 나타났으며 동일 수지나 동일 처리구에서는 heating temperature가 증가함에 따라 용융지수가 증가한 것으로 나타났다. 상용화제 4%를 첨가한 BDP-2 처리구에서 토출양도 비중도 우수한 것으로 조사되었으며, MD 및 TD 방향의 인장강도도 높게 나타나 BDP-2가 복합화 생분해 필름 제조용 제조 방법으로 가장 적합한 것으로 사료되었다.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제3권3호
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• pp.139-148
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• 2022

Saxifraga hirculus is classified as a vulnerable plant species in Europe, and it is confined to base-rich flushes in the British uplands. However, a lack of available information about its conservation status hampers the development of adaptive strategies for its in-situ conservation, especially with respect to grazing. To assess the effectiveness of sheep grazing in maintaining viable populations of S. hirculus, we compared the community dynamics of the vegetation in a base-rich flush over 44 years in two plots: one sheep-grazed under business-as-usual sheep grazing densities and the other fenced to exclude grazing. The plots were established in 1972, and the abundances of all vascular plants, bryophytes, and litter were measured at six intervals until 2016. Our results showed that although the presence of S. hirculus was maintained in both plots over the 44 years, it declined and reached a minimum between 1995 and 2010, when it was close to extinction. Since 2013, Saxifraga has recovered only slightly. Interestingly, the S. hirculus response appeared to be independent of grazing treatment, but it mirrored wider changes in the vegetation composition and structure within the flush over the 44 years. These changes are similar to others reported in broader uplands that have been attributed to a combination of reduced nitrogen and sulfur deposition and global warming. Thus, the simple adaptive management approach of "just managing" sheep grazing appeared ineffectual for preserving the S. hirculus population. S. hirculus showed signs of recovery at the end of the study period within this base-rich flush.

• 한국지반신소재학회논문집
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• 제22권2호
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• pp.13-21
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• 2023

최근 지구온난화 등으로 인하여 지구의 평균해수면이 상승하는 추세이다. 삼면이 바다인 국내의 경우 연안침식이 초래되어 국토 손실 및 연안의 위험성을 높일 가능성이 있다. 미생물에 의한 탄산칼슘 형성(MICP) 기술은 미생물에 의한 탄산칼슘침강 기술이며, 지반의 강성과 강도를 증진시키는 친환경적 방법이다. 본 연구에서는 연안 침식 저감을 위하여 MICP 기술을 제안하였다. 연안 조건을 고려하여 용매로 해수를 사용하고 탈염수와 그 성능을 비교하였다. 탈염수와 해수 조건하에서 미생물에 의한 요소분해능을 조사하였다. 소일칼럼을 제작하여 MICP 처리된 모래의 강도 평가를 실시하였다. MICP 처리는 표면살포법에 의해 처리되었는데, 이러한 방식은 기존의 혼합 방식과 달라 전통적인 강도 평가 방식은 적절하지 않음을 확인하였다. 미세 구조 분석을 통해 다른 용매가 사용된 경우의 광물적 변화를 관측하였다. 실험 결과, 해수는 미생물에 의한 요소분해 반응을 느리게 만드는 것을 확인하였다. 표면 경화된 모래는 침관입시험을 통해 효과적으로 평가할 수 있었다. 이 연구에서는 해수를 용매로 사용하여도 탈염수 수준으로 충분히 MICP 기술 적용이 가능함을 확인하였다.

• 청정기술
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• 제26권2호
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• pp.145-150
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• 2020

아산화질소(N₂O)는 6대 온실가스 중 하나로 이산화탄소(CO₂)의 310배에 해당하는 지구온난화지수(global warming potential, GWP)를 나타내어 N₂O를 저감하는 것은 필수적이다. 선택적 촉매환원법(selective catalytic reduction, SCR)은 대기오염 물질의 하나인 NOx의 제거를 위해 암모니아를 환원제로 사용하여 무해한 N₂ 및 H₂O로 전환하는 기술로 높은 탈질효율을 나타낸다. 본 연구에서는 NH₃-SCR반응에서 스팀 처리된 Fe-BEA 촉매가 활성에 미치는 영향을 조사하기 위하여 Fe-BEA 촉매는 Fe를 이온교환하기 전, 고정층 반응기로 100 ℃에서 2 h 동안 스팀 처리 되었다. 제조된 촉매의 NH₃-SCR반응 테스트는 고정층 반응기로 WHSV = 180 h^-1, 370 ~ 400 ℃에서 수행되었다. 100 ℃에서 스팀 처리된 Fe-BEA(100) 촉매가 370 ~ 390℃에서 Fe-BEA 촉매보다 다소 높은 활성을 나타내었다. NH₃-SCR 활성에 영향을 주는 원인을 파악하기 위하여 제조된 촉매는 BET, ICP, NH₃-TPD, H₂-TPR, ²⁷Al MAS NMR을 통하여 특성분석 되었다. H₂-TPR결과를 통해 Fe-BEA(100) 촉매가 Fe-BEA 촉매 보다 isolated Fe³⁺의 환원이 더 많이 일어난 것을 확인하였으며, 스팀 처리는 활성종인 isolated Fe³⁺의 양을 늘려주어 활성이 증가한 것으로 판단된다.

• 한국환경농학회지
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• 제28권3호
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• pp.233-237
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• 2009

It has widely been observed that the effect of elevating atmospheric $CO_2$ concentrations on rice productivity depends largely on soil N availabilities. However, the responses of ammonia volatilization from flooded paddy soil that is an important pathway of N loss and thus affecting fertilizer N availability to concomitant increases in atmospheric $CO_2$ and temperature has rarely been studied. In this paper, we first report the interactive effect of elevated $CO_2$ and temperature on ammonia volatilization from rice paddy soils applied with urea. Urea labeled with $^{15}N$ was used to quantitatively estimate the contribution of applied urea-N to total ammonia volatilization. This study was conducted using Temperature Gradient Chambers (TGCs) with two $CO_2$ levels [ambient $CO_2$ (AC), 383 ppmv and elevated $CO_2$ (EC), 645 ppmv] as whole-plot treatment (main treatment) and two temperature levels [ambient temperature (AT), $25.7^{\circ}C$ and elevated temperature (ET), $27.8^{\circ}C$] as split-plot treatments (sub-treatment) with triplicates. Elevated temperature increased ammonia volatilization probably due to a shift of chemical equilibrium toward $NH_3$ production via enhanced hydrolysis of urea to $NH_3$ of which rate is dependent on temperature. Meanwhile, elevated $CO_2$ decreased ammonia volatilization and that could be attributed to increased rhizosphere biomass that assimilates $NH_4^+$ otherwise being lost via volatilization. Such opposite effects of elevated temperature and $CO_2$ resulted in the accumulated amount of ammonia volatilization in the order of ACET>ACAT>ECET>ECAT. The pattern of ammonia volatilization from applied urea-$^{15}N$ as affected by treatments was very similar to that of total ammonia volatilization. Our results suggest that elevated $CO_2$ has the potential to decrease ammonia volatilization from paddy soils applied with urea, but the effect could partially be offset when air temperature rises concomitantly.