• Ocean and Polar Research
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• 제41권4호
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• pp.275-288
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• 2019

We investigated flux, grain size distribution, Nd-Sr isotope composition, mineral composition, and trace metal composition (REEs and Sc) of inorganic silicate fraction (ISF, mainly Asian dust with an unrestricted amount of volcanic materials) deposited during 600~1000 ka across the Mid-Pleistocene Transition at core NPGP 1401-2A (32°01'N, 178°59'E, 5205m) taken from the central part of the North Pacific. Our results reveal about a 2-fold increase in ISF flux after 800 ka, which is associated with an increase in La/Sc and a decrease in mean grain size. Asian dusts are finer than volcanic materials and La/Sc increases with the enhanced contribution of Asian dusts. Thus, increased flux after 800 ka can be explained by the increased contribution of Asian dusts relative to volcanic materials, likely due to an intensified Westerly Jet (WJ) and the drying of the Asian continent after the MPT. Mean grain size of ISF varies systematically in relation to glacial-interglacial cycles with a decrease during glacial stages, which is consistent with the previous results in the study area. Such a cyclical pattern is also attributed to the increase in the relative contribution of Asian dusts over volcanic components in glacial stages due to intensified WJ and drying of the Asian continent. Thus, it can be concluded that climate changes that had occurred across the MPT were similar to those of interglacial to glacial transitions at least in terms of the dust budget. Different from the Shatsky Rise, however, compositional changes associated with glacial-interglacial mean grain size fluctuations are not observed in Nd-Sr isotope ratios and trace element composition in our study of the Hess Rise. This may be attributed to the location of the study site far (> 4,000 km) from the volcanic sources. The volcanic component at the study site comprises less than 10% and varies within 3% over glacial-interglacial cycles. Such a small variation was not enough to imprint geochemical signals.

• 대한화장품학회지
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• 제46권3호
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• pp.273-282
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• 2020

알로에 베라(Aloe barbadensis Miller)는 예로부터 화상이나 상처, 습진 등의 다양한 피부 질환을 개선하기 위해 사용해 왔다. 이러한 효능은 알로에가 가지고 있는 비타민, 무기질, 당, 페놀 물질, 지방산. 아미노산 등의 다양한 성분에 의한 것으로 보고가 되었다. 알로에는 극한의 환경에서 스스로를 보호하기 위해서 성분을 변화시키며, 이로 인해 색깔이 녹색에서 적색으로 변화한다. Aloe-emodin은 알로에속 식물의 대표적인 페놀성 물질로 항산화 및 항염 활성을 나타낸다. 그러나 지금까지 알로에의 활성 물질인 알로에-에모딘을 증가시키고 알로에의 색상을 변화시키는 공정 개발에 대한 연구는 보고되지 않았다. 따라서 본 연구의 목적은 aloe-emodin 함량을 증가시키고 알로에의 항산화 및 항염 활성을 증대시키는 핑크 알로에 제조공정을 개발하는 것이다. 이를 위해 알로에를 적정 조건으로 가온한 결과 핑크 알로에는 일반 알로에 대비 aloe-emodin 함량이 증가하였으며, 항산화 활성 증대, NO 생성 억제, 세포 재생 촉진 등의 효과를 나타내었다. 본 연구를 통해 화장품 분야에서 핑크 알로에의 신규 항노화 소재로 활용성을 확인하였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.21-21
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• 2017

Severe lodging has recurrently occurred at strong typhoon's hitting in recent climate change. The identification of quantitative trait loci (QTLs) and their responsible genes associated with a strong culm and their pyramiding are important for developing high-yielding varieties with a superior lodging resistance. To identify QTLs for lodging resistance, the tropical japonica line, Chugoku 117 and the improved indica variety, Habataki were selected as the donor parent, as these had thick and strong culms compared with the temperate japonica varieties in Japan such as Koshihikari. By using chromosome segment substitution lines (CSSLs) in which chromosome segments from the japonica variety were replaced to them from Habataki, we identified the QTLs for strong culm on chrs. 1 and 6, which were designated as STRONG CULM1 (SCM1) and STRONG CULM2 (SCM2), respectively. By using recombinant inbred lines (BILs) derived from a cross between Chugoku 117 and Koshihikari and introgression lines, we also identified the other QTLs for strong culm on chrs. 3 and 2, which were designated as STRONG CULM3 (SCM3) and STRONG CULM4 (SCM4), respectively. Candidate region of SCM1 includes Gn1 related to grain number. SCM2 was identical to APO1, a gene related to the control of panicle branch number, and SCM3 was identical to FC1, a strigolactone signaling associated gene, by performing fine mapping and positional cloning of these genes. To evaluate the effects of SCM1~SCM4 on lodging resistance, the Koshihiakri near isogenic line (NIL) with the introgressed SCM1 or SCM2 locus of Habataki (NIL-SCM1, NIL-SCM2) and the another Koshihikari NIL with the introgeressed SCM3 or SCM4 locus of Chugoku 117 (NIL-SCM3, NIL-SCM4) were developed. Then, we developed the pyramiding lines with double or triple combinations derived from step-by-step crosses among NIL-SCM1 NIL-SCM4. Triple pyramiding lines (NIL-SCM1+2+3, ~ NIL-SCM1+3+4) showed the largest culm diameter and the highest culm strength among the combinations and increased spikelet number due to the pleiotropic effects of these genes. Pyramiding of strong culm genes resulted in much increased culm thickness, culm strength and spikelet number due to their additive effect. SCM1 mainly contributed to enhance their pyramiding effect. These results in this study suggest the importance of identifying the combinations of superior alleles of strong culm genes among natural variation and pyramiding these genes for improving high-yielding varieties with a superior lodging resistance.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.314-314
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• 2017

Anthropogenic activities have increased the concentrations of greenhouse gases, such as $CO_2$, $CH_4$, $N_2O$, HFCs, $SF_6$, and PFCs, in the atmosphere. Among others, $N_2O$ is well known as an important greenhouse gas accounting for 7.9% of the total greenhouse effect and the effect of its emission is 310 times greater than that of $CO_2$. Agricultural $N_2O$ emissions are now thought to contribute to about 60% of the global anthropogenic $N_2O$ emission, which have been increased primarily due to fertilizer N consumption and manure management. Therefore, the reduction of $N_2O$ emissions in agriculture is being required. This study was conducted to determine the variation of $N_2O$ emissions by no-tillage (NT) and conventional tillage (CT) practices in the cultivation of soybean from the sandy loam soils under the different kinds of fertilizer treatments June through September 2016 in Cheong-ju, Republic of Korea. An experimental plot, located in the temperate climate zone, was composed of two main plots that were NT and CT, and were divided into four plots, respectively, in accordance with types of fertilizers (chemical fertilizer, liquid pig manure, hairy vetch and non-fertilizer). Among all the treatments, $N_2O$ emission was the highest in August and the lowest in June. When $N_2O$ emissions were evaluated during the growing season (June to September) in all fertilizer treatments, NT with hairy vetch treatment emitted the highest $N_2O$ emission in August, whereas, $N_2O$ emissions was the lowest in NT with non-fertilizer treatment in June, respectively (p = 0.05). Based on the cumulative amount of $N_2O$ emissions during the growing season of soybean, NT had lower $N_2O$ emission than CT by 0.01 - 0.02 kg $N_2O$, although NT had higher $N_2O$ emission than CT by 0.03 kg $N_2O$ in only the chemical fertilizer treatments. As a result, it seems that the applications of liquid pig manure and hairy vetch rather than chemical fertilizer could decrease the $N_2O$ emission in NT, compared to CT.

• 한국물환경학회지
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• 제33권4호
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• pp.434-440
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• 2017

In order to understand the characteristics of phosphorus in the paddy field, this study analyzed $PO_4-P$ and T-P concentrations of irrigation water, flooding water, and runoff from 2008 to 2010. The variation of phosphorous form within hydrologic cycle around the rice paddy field was investigated using the ratio of $PO_4-P$ to TP. In addition, the correlation between pH, EC, and DO in flooding water was analyzed and the factors affecting phosphorus form in paddy field were investigated. The concentration of T-P in flooding water was high during the survey period, and the concentration of T-P in runoff was assumed to be decreased by dilution due to irrigation and rainfall. On the other hand, the ratio of $PO_4-P$ to T-P was lower in flooding water than those of irrigation water and runoff, which was interpreted to be due to the fact that the phosphorus fertilizer was applied in the paddy field but the adsorption was rapidly occurred to the paddy field by the soil. The similar proportions of $PO_4-P$ to T-P in flooding water and runoff suggest that the form of phosphorus outflowed from the paddy is influenced by the form of phosphorus in the flooding water of paddy field. In addition, DO concentration in flooding water showed negative correlation with the concentrations of $PO_4-P$ and T-P. The effort to survey frequent irrigation water quality data is required for the analysis of phosphorus behavior in the paddy water system since concentration of phosphorous and DO in irrigation water would influence rhe form of phosphorous in flooding water and subsequent runoff.

• 한국지구과학회지
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• 제26권6호
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• pp.597-602
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• 2005

무안군 피서리 유적지에 노출된 후기 제4기층에서 포자$\cdot$화분 분석결과，낙엽성 활엽수　화분이 주종을 이루고 있으며 초본류와 침엽수 화분도 풍부하게 산출되었다. 대표적인 종류로는 고란초과, 낙우송과-측백과-주목과, 오리나무속, 서어나무속, 낙엽성 참나무속, 국화과 및 벼과 등이다. 탄소연대측정 결과, 그 생성 시기가 지난 최후 빙하기에 해당하는 43,000-18,000 yr BP 로 측정된 이 포자$\cdot$화분군은 오늘날 한반도 중부의 한랭한 온대 낙엽성 활엽수림의 식생과 유사하다. 전체적인 식생 조성에 근거하여 3개의 포자$\cdot$화분 분대를 설정하였다. Zone I은 고란초과, 낙우송과-측백과-주목과, 오리나무속 및 낙엽성 나무속 등으로 이루어진 한랭한 온대의 낙엽성 활엽수림을 지시하며 특징적으로 난대종이 지속적으로 산출된다. Zone II에서는 고란초과와 낙우송과-측백과-주목과 등이 뚜렷하게 감소하고 초본류가 증가하는 양상을 보이는데 이는 당시에 한랭한 온대의 낙엽성 활엽수림과 함께 부분적으로 초지가 분포했음을 의미한다. Zone III에서는 초본류의 지속적인 산출과 함께 침엽수가 증가하는 경향을 보인다. 피서리 포자·화분군의 식생 조성은당시의 기후가 한랭한 온대였다는 것을 지시하며 시간이 흐르면서 점차 한랭·건조해진 것으로 해석된다.

• 한국산림과학회지
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• 제101권3호
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• pp.395-404
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• 2012

본 연구는 환경인자를 이용하여 우리나라에 분포하는 주요 침엽수종(중부지방소나무, 강원지방소나무, 낙엽송, 잣나무)의 지위지수 추정식을 개발하고 적지면적을 추정하기 위해 수행하였다. 이를 위해 산림입지도와 산림기후도로부터 산림생산력에 영향을 미칠 것으로 판단되는 43개 환경인자를 도출한 후, 최적 조합에 의해 수종별 지위지수 추정식을 조제하였다. 최종 수종별 지위지수 추정식에는 각각 6개의 환경인자가 독립변수로 사용되었으며, 경사형태, 유효 토심, 연 평균기온, 연 최고기온, 연 최저기온, 그리고 생장기간 동안의 총강수량 등의 변수가 지위지수 추정에 가장 영향을 미치는 것으로 나타났다. 수종별 지위지수 추정식의 설명력을 나타내는 결정계수는 0.36~0.56의 범위에 있는 것으로 분석되었으며, 모형의 평균편의, 정도, 표준오차의 3가지 평가통계량에 근거하여 검증을 실시한 결과 비교적 지위 추정능력이 높은 것으로 판명되었다. 또한 본 연구에서는 수종별 지위지수 추정식을 이용하여 각 수종의 적지면적을 산출하고 적지분포를 도해하였다.

• Ocean and Polar Research
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• 제37권2호
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• pp.127-140
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• 2015

A continuous series of 60 snow samples was collected at a 2.5-cm interval from a 1.5-m snow pit at a site on the Styx Glacier Plateau in Victoria Land, Antarctica, during the 2011/2012 austral summer season. Various chemical components (${\delta}D$, ${\delta}^{18}O$, $Na^+$, $K^+$, $Mg^{2+}$, $Ca^{2+}$, $Cl^-$, $SO_4{^2-}$, $NO_3{^-}$, $F^-$, $CH_3SO_3{^-}$, $CH_3CO_2{^-}$ and $HCO_2{^-}$) were determined to understand the highly resolved seasonal variations of these species in the coastal atmosphere near the Antarctic Jang Bogo station. Based on vertical profiles of ${\delta}^{18}O$, $NO_3{^-}$and MSA, which showed prominent seasonal changes in concentrations, the snow samples were dated to cover the time period from 2009 austral winter to 2012 austral summer with a mean accumulation rate of $226kgH_2Om^{-2}yr^{-1}$. Our snow profiles show pronounced seasonal variations for all the measured chemical species with a different pattern between different species. The distinctive feature of the occurrence patterns of the seasonal variations is clearly linked to changes in the relative strength of contributions from various natural sources (sea salt spray, volcanoes, crust-derived dust, and marine biogenic activities) during different short-term periods. The results allow us to understand the transport pathways and input mechanisms for each species and provide valuable information that will be useful for investigating long-term (decades to century scale periods) climate and environmental changes that can be deduced from an ice core to be retrieved from the Styx Glacier Plateau in the near future.

• 한국조경학회지
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• 제36권1호
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• pp.80-89
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• 2008

Generally, trees lining the streets are the most easily accessible green areas in the city and constitute the smallest basic unit in the formation of the urban linear green axis. This study attempts to interpret issues related to city trees from a comprehensive and relational viewpoint. The site of this study is Central Park Street in front of Incheon Metropolitan City Hall. This street is representative of those in Incheon City. This study is an inter-relational interpretation of issues by measuring the vitality of these trees. The following are results of this study: First, the vitality of city trees is higher in those trees growing in natural ground than those growing in plant gratings. This observation can lead to budget savings and increased natural areas in the city. Also, if planter and multi-layering planting methods are introduced where damage to trees is predicted, variation to urban landscape can be achieved while linking to reinforced rearing foundation of street-side trees. Second, there is need for a holistic approach to caring for street-side trees regarding the damage caused by drastic pruning and strong street lights. The typical functions of these trees, like supplying freshness in summer, absorbing solar radiation, and controlling the urban micro-climate are closely related to the vitality of the trees. Accordingly, the function and ecology should be understood holistically, not separately. In this aspect, the functional and ecological use of the multi-layering planting method is effective in protecting pedestrians from vehicles as well. Third, the fallen leaves of monotonous rows of trees have different ecological and functional effects. Not only is the index of greenness in the urban setting increased, but there are also aesthetic and symbolic effects. Fourth, in spite of being the street along which Incheon Metropolitan City Hall, major administrative buildings and Central Park are located, this street does not have its own special identity to discriminate it from other streets. It fulfills only functional criteria based on uniformity. If there is no paradigm shift from today's street system based on vehicles, the role of landscape architecture will be very passive in regards to street-side trees, the minimum unit of urban green. Fifth, on this particular street, many trees were planted in December, which reflects a deficiency of short and long-term strategy, like a street-tree master plan. In this aspect, we still lack a mature culture concerning these trees as a basic unit in urban greenery. Furthermore, there needs to be cultural introspection concerning present administrative practices.

• Asian Journal of Atmospheric Environment
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• 제7권4호
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• pp.177-190
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• 2013

Air pollution trends in Japan between 1970 and 2012 were analyzed, and the impact of air pollution countermeasures was evaluated. Concentrations of CO decreased from 1970 to 2012, and in 2012, the Japanese environmental quality standard (EQS) for CO was satisfied. Concentrations of $SO_2$ dropped markedly in the 1970s, owing to use of desulfurization technologies and low-sulfur heavy oil. Major reductions in the sulfur content of diesel fuel in the 1990s resulted in further decreases of $SO_2$ levels. In 2012, the EQS for $SO_2$ was satisfied at most air quality monitoring stations. Concentrations of $NO_2$ decreased from 1970 to 1985, but increased from 1985 to 1995. After 1995, $NO_2$ concentrations decreased, especially after 2006. In 2012, the EQS for $NO_2$ was satisfied at most air quality monitoring stations, except those alongside roads. The annual mean for the daily maximum concentrations of photochemical oxidants (OX) increased from 1980 to 2010, but after 2006, the $98^{th}$ percentile values of the OX concentrations decreased. In 2012, the EQS for OX was not satisfied at most air quality monitoring stations. Non-methane hydrocarbon (NMHC) concentrations generally decreased from 1976 to 2012. In 2011, NMHC concentrations near roads and in the general environment were nearly the same. The concentration of suspended particulate matter (SPM) generally decreased. In 2011, the EQS for SPM was satisfied at 69.2% of ambient air monitoring stations, and 72.9% of roadside air-monitoring stations. Impacts from mineral dust from continental Asia were especially pronounced in the western part of Japan in spring, and year-round variation was large. The concentration of $PM_{2.5}$ generally decreased, but the EQS for $PM_{2.5}$ is still not satisfied. The air pollution trends were closely synchronized with promulgation of regulations designed to limit pollutant emissions. Trans-boundary OX and $PM_{2.5}$ has become a big issue which contains global warming chemical species such as ozone and black carbon (so called SLCP: Short Lived Climate Pollutants). Cobeneficial reduction approach for these pollutants will be important to improve both in regional and global atmospheric environmental conditions.