• 자연과학논문집
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• 제11권1호
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• pp.75-84
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• 1999

1995년 5월부터 1996년 6월까지 한강 하류지역을 대상으로 Ponar grab과 basket sampler 등을 이용하여 저서동물상을 조사하였다.그 결과 총 3문 7강 8목 12과 14종이 서식하고 있는 것으로 나타났다. 이중 환형동물은 3종, 연체동물은 4종, 절지동물은 7종으로 나타났다. 환형동물은 전 조사정점에서 출현하였으며 참갯지렁이(Neanthe japonica)가 우점종으로 나타났다. 현존량은 정점 4를 기점으로 상류와 하류로 갈수록 감소하는 양상을 보였고, 시기별로는 1995년 5월부터 감소하기 시작하여 1995년 10월에 급격히 감소하였다가 1996년부터 약간 증가하는 양상을 보였으나 대체적으로 생물상이 불안정한 상태를 보였다.

• Animal cells and systems
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• 제16권3호
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• pp.260-267
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• 2012

Calling behavior is often used to infer breeding patterns in anurans. We studied the seasonal and diel calling activities of anuran species in a wetland in central Korea to determine the calling season and to evaluate the effects of abiotic factors on male calling. Acoustic monitoring was used in which frog calls were recorded for a full day, once a week, throughout an entire year. Using acoustic monitoring, we identified three frog species in the study site. Males of Rana dybowskii called in late winter and early spring; we thus classified this species as a winter/spring caller. The results of binary logistic regression showed that temperature, relative humidity, and 1-day lag rainfall were significant factors for male calling in R. dybowskii. Temperature and relative humidity were important factors for the calling activity of R. nigromaculata, whereas 24-h rainfall and 1-day lag rainfall were not significant. Thus, we determined R. nigromaculata to be a summer caller independent of weather. In Hyla japonica, relative humidity, 24-h rainfall, and 1- day lag rainfall were significant for male calling, suggesting that this species is a summer caller dependent on local rain.

• Animal Systematics, Evolution and Diversity
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• 제8권2호
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• pp.163-176
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• 1992

3종의 외국산 따개비가 한국의 조간대 해역에 침입한 것이 발견되었는데 이들은 Balanus amphitrite, B. eburneus 및 B. improvisus이다. 한국내에서 이 3종이 모두 발견되고 개체군이 가장 발달된 곳은 동남부 해역, 즉 부산 부근이다. B. amphitrite는 1970년도 초에 가장 먼저 한국에 침입한 것으로 추측되며 가장 널리 분포해 있으나 목포 이북의 서해에는 아직 침입해 있지 않은 상태이다. B. improvisus는 동해의 복쪽까지 확산해 있으나 B. eburneus는 동남부 해역에 국한되어 있다. B. amphitrite는 재래종인 B. albicostatus와 경쟁을 하고 있는데 이 두 종이 혼생하고 있는 여러 지역에서 후자의 재래종이 배타되고 있는 실정이다. 서해는 아직 외래 따개비의 침입을 받고 있지 않은데 그 이유는 현재 모르고 있다.

• Journal of Ecology and Environment
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• 제42권4호
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• pp.150-154
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• 2018

In lotic wetlands, runner reed (Phragmites japonicus) plays a role as a pioneer, which helps other plant species to settle by making dense roots trapping floating-sediments. In lentic wetlands, on the other hand, P. japonicus could play a role as an invader threatening biodiversity by forming tall and dense stands. To conserve an abandoned paddy terrace in mountainous areas, a habitat of an endangered dragonfly species (Nannophya pygmaea), from the monotypic-occupation by P. japonicus, we applied three kinds of treatment: (1) hand-clipping in 2009, (2) mechanical excavating in 2012, and (3) planting of alternative vegetational unit in 2012. We have monitored vegetation changes in the wetland in 2008~2012 and 2017. Vegetation cover of P. japonicus sharply decreased from 43% in 2011 to 16% in 2012 by the mechanical excavation. After 5 years from applying the treatment, Schoenoplectiella mucronata that was utilized in the planting became the predominant species instead of P. japonicus and the number of wetland plant species increased from 16 to 25 with the shift in species composition. This study showed the utility of three control methods of P. japonicas in a lentic wetland.

• Journal of the Korean Wood Science and Technology
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• 제47권3호
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• pp.324-335
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• 2019

Timber from plantation forests has inferior physical and mechanical properties compared to timber from natural forest because it is mostly from fast-growing tree species that are cut at a young age. Filling cell voids with methyl methacrylate (MMA) can improve the wood properties. The purpose of this study was to determine the physical and mechanical properties of MMA-impregnated wood from three fast-growing wood species, namely jabon (Anthocephalus cadamba (Roxb.) Miq.), mangium (Acacia mangium Willd) and pine (Pinus merkusii Jungh. & de Vriese). Wood samples were either immersed in MMA monomer or impregnated with it and then heated to induce the polymerization process. Jabon, which was the lowest density wood, had the highest polymer loading, followed by pine and mangium. The physical and mechanical properties of samples were affected by wood species and the presence of MMA, with higher-density wood having better properties than wood with a lower density. Physical and mechanical properties of MMA wood were enhanced compared to untreated wood. Furthermore, the impregnation process was better than immersion process resulting the physical and mechanical properties. Based on MOR values, the MMA woods were one strength class higher compared to untreated wood with regard to Strength Classification of Indonesian Wood.

• Journal of Ecology and Environment
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• 제45권4호
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• pp.218-227
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• 2021

Background: Artificial light at night has recently been identified as a major factor adversely affecting global insect diversity. Here, we compared the insect diversity in Gwangneung Forest Biosphere Reserve, specifically in the Korea National Arboretum (with no artificial light at night), with that of three nearby urban sites with a gradient of artificial light at night (five locations at each site). We analyzed the effects of the artificial night lighting index, mean annual temperature, and field light intensity (lux) at night on the insect community structure. Results: The urban sites generally exhibited higher species richness and abundance as well as clear indicator species compared with the control site. The size distribution of the collected insects markedly differed between the control and the three urban sites. The abundance of herbivorous and omnivorous insects increased and decreased, respectively, with the increase in light intensity. Species richness of herbivorous and omnivorous insects was likely correlated with the field light intensity at night and artificial night lighting index, respectively. Conclusions: This study demonstrates the association between nighttime environment and marked changes in insect community structure and revealed consequent transition of ecosystem services by changes in trophic group composition.

• Journal of Animal Science and Technology
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• 제64권1호
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• pp.97-109
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• 2022

Species are facing strong selection pressures to adapt to inhospitable high-altitude environments. Yaks are a valuable species and an iconic symbol of the Qinghai-Tibet Plateau. Extensive studies of high-altitude adaptation have been conducted, but few have focused on metabolism. In the present study, we determined the differences in the serum metabolomics between yaks and the closely related species of low-altitude yellow cattle and dairy cows. We generated high-quality metabolite profiling data for 36 samples derived from the three species, and a clear separation trend was obtained between yaks and the other animals from principal component analysis. In addition, we identified a total of 63 differentially expressed metabolites among the three species. Functional analysis revealed that differentially expressed metabolites were related to the innate immune activation, oxidative stress-related metabolism, and energy metabolism in yaks, which indicates the important roles of metabolites in high-altitude adaptation in yaks. The results provide new insights into the mechanism of adaptation or acclimatization to high-altitude environments in yaks and hypoxia-related diseases in humans.

• Animal Systematics, Evolution and Diversity
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• 제39권4호
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• pp.176-211
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• 2023

Nine copepod species of the family Artotrogidae Brady, 1880 are described or redescribed from Korea. Included new species are two in the genus Artotrogus Boeck, 1859, one each in the genera Bradypontius Giesbrecht, 1895, Cryptopontius Giesbrecht, 1899, Neopontius Scott T., 1898 and Chejupontius n. gen., and two in the genus Sewellopontius Ummerkutty, 1966. Chejupontius n. gen. resembles Ascidipontius Kim I. H., 1996, Pulicitrogus Kim I. H., 1998, and Sewellopontius in having reduced armature of leg 1, but is distinguished from these and other genera of the family by the large, mediodistally expanded protopod of leg 5 and by a combination of characters exhibited in leg 1 that the first exopodal segment lacks an inner seta, the second exopodal segment lacks an outer spine, the third exopodal segment is armed with three spines plus one to three setae, and the second endopodal segment is armed with a single inner seta. Pteropontius cristatus Giesbrecht, 1895 known previously only from the Mediterranean Sea is redescribed, based on a newly collected specimen from Korea, and P. trimerus Kim I. H., 1996 is removed to the genus Sewellopontius. A short note is given for the epibiotic suctorian Thecacineta calix (Schroder, 1907) which was found attached to the antennule of a new copepod species.

• Molecules and Cells
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• 제26권3호
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• pp.314-318
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• 2008

Korean long-tailed goral (Nemorhaedus caudatus) is one of the most endangered species in South Korea. However, detailed species distribution and sex ratio data on the elusive goral are still lacking due to difficulty of identification of the species and sex in the field. The primary aim of this study was to develop an economical PCR-RFLP method to identify species using invasive or non-invasive samples from five Korean ungulates: goral (N. caudatus), roe deer (Capreolus pygargus), feral goat (Capra hircus), water deer (Hydropotes inermis) and musk deer (Moschus moschiferus). The secondary aim was to find more efficient molecular sexing techniques that may be applied to invasive or non-invasive samples of ungulate species. We successfully utilized PCR-RFLP of partial mitochondrial cytochrome b gene (376 bp) for species identification, and sex-specific amplification of ZFX/Y and AMELX/Y genes for sexing. Three species (goral, goat and water deer) showed distinctive band patterns by using three restriction enzymes (Xbal, Stul or Sspl). Three different sexing primer sets (LGL331/335 for ZFX/Y gene; SE47/48 or SE47/53 for AMELX/Y gene) produced sex-specific band patterns in goral, goat and roe deer. Our results suggest that the molecular analyses of non-invasive samples might provide us with potential tools for the further genetic and ecological study of Korean goral and related species.

• Journal of Animal Science and Technology
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• 제46권3호
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• pp.443-450
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• 2004

본 시험은 혼파조합이 하번초형 혼파초지의 건물수량과 사료가치에 미치는 영향을 구명하여 하번초형 혼파초지를 조성하는데 적합한 혼파조합을 찾고자 1998년 9월부터 2001년 12월까지 충남대학교 생명과학대학내 부속 초지시험포장에서 수행하였다. 공시 혼파조합은 tall fescue, kentucky bluegrass 및 perennial ryegrass 중심의 3가지 혼파조합을 공시하였으며 얻어진 시험결과는 다음과 같다 1) 3년 평균 ha당 건물수량, 일반화학적 성분, 건물소화율과 조단백질수량(CPDM) 및 가소화건물수량(DDM)은 혼파조합간에차이가 없었다. 2) 2001년도 6회 마지막 예취시 tall fescue, Kentucky bluegrass 및 perennial ryegrass 중심의 혼파조합에서 tall fescue, Kentucky bluegrass 및 perennial ryegrass의 식생 비율은 각각 42, 35 및 28%이었고, 전체 초종에서 이들 3초종이 차지하는 식생 비율은 모든 혼파조합에서 84%로 나타나 혼파조합이 식생비율에 미치는 영향은 크지 않았다. 기타 초종 중에서는 redtop(8%)과 creeping bentgrass(6${\sim}$7%)의 식생비율이 낮았으며, 특히 red fescue(1${\sim}$2%)는 매우 낮은 식생비율이 보였다. 이상의 결과를 종합해 볼 때, 혼파조합간에 건물수량과 사료가치 및 식생비율에 뚜렷한 차이가 없었던 것으로 보아, tall fescue, Kentucky bluegrass 및 perennial ryegrass 중심의 어느 혼파조합으로 하번초형 혼파초지를 조성하여도 공익목적과 부수적으로 생산되는 목초를 조사료원으로 활용가능성은 크다고 하겠다.