• Title/Summary/Keyword: Warm zone

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CALCAREOUS NANNOPLANKTON FROM THE SEOGUIPO FORMATIN OF CHEJU ISLAND, KOREA AND ITS PALEOCEANOGRAPHIC IMPLICATIONS

  • Yi Songsuk;Yun Hyesu;Choi Duck-Keun;Yoon Sun;Koh Gi-Won
    • 한국석유지질학회:학술대회논문집
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    • spring
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    • pp.22-28
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    • 1998
  • Twenty species of calcareous nannofossils belonging to 11 genera are identified from the Seoguipo Formation in Cheju island, Korea. On the basis of the marker species, the Seoguipo Formation is biostratigraphically assigned to the Pseudoemiliania lacunosa Zone (NNl9), which corresponds to the combined zones of Emiliania annula - Emiliania ovata (CN13a-CN14a) of latest Pliocene and Early Pleistocene. Generally, cold-water species is dominant in the lower part, whereas warm-water one in the upper part. This is interpreted the palaeoceanographic condition has changed from cooling to warm phase. The change in floral composition and abundance of specific species allows the recognition of 4 ecostaratigraphic units in the Seoguipo Formation and the migration of oceanographic frontal boundary. According to nannofossil distribution in the study area, the position of an oceanographic boundary between warmer water and cooler water appeared to have oscillated north-south over the Korea Strait and Cheju island in response to glacial and interglacial cycles. The geologic time of the interpreted paleoceanographical changes determined by nannofossil biochronology is well agreed with the results obtained from the Japan Sea (East Sea) and Japan-Sea side of Japan.

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A Study on the Color Image Preference of the classroom in kindergarten (유치원 교실의 색채이미지 선호도에 관한 연구)

  • 정가영;이향미;이청웅
    • Korean Institute of Interior Design Journal
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    • v.13 no.5
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    • pp.190-197
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    • 2004
  • A kindergarten requires an approach to meet the nature and sense of children who is main users. This study selected 33 private kindergartens which were located within a housing site development zone in Gwangju since the 1990's, had single use, and was constructed in the last five years. Also the image assessment according to types of color scheme was made. Then the factors which affected preference by type were analyzed and the basic of color scheme in a kindergarten classroom was provided. The following results were obtained. First, types of color scheme in a classroom included identity 12.1%, similarity 51.5%, and novelty 36.4% in harmony, but no contrast and achromatic color, Secondly, the assessment of preference according to each type was mostly positive. The highest preference was found in similarity harmony of warm color(e.g. YR, Y) and bright, clear, nice, and strong images were high in assessment. The lowest preference was found in identity harmony of cold color(e.g. GY). This color system had no clear image assessment, except manly or strong. In particular, warm color showed higher preference than cold color in similarity, novelty, and identity harmony. Thirdly, the factors affecting the preference of color scheme in a classroom most were ‘stable - unstable’, ‘clean - dirty’, ‘bright - dark’, ‘nice - not nice’, and ‘vital - dull’.

Vegetation Structure of the Dogabsa Valley in the Weolchulsan National Park (월출산국립공원 도갑사계곡의 식생구조)

  • Choi Song-Hyun;Cho Hyun-Seo
    • Korean Journal of Environment and Ecology
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    • v.20 no.2
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    • pp.94-102
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    • 2006
  • To investigate the forest structure and to suggest basic data of forest in the Dogabsa Valley area of the Weolchulsan National Park, thirty plots, each size is $100m^2$, were set up and surveyed. According to the analysis of classification by TWINSPAN, the community was divided by five groups of Quercus variabilis-Carpinus tschonoskii(I), Pinus densiflora(II), Q. variabilis-P. densiflora(III), Q. variabilis(IV) and Q. aliena-Styrax japonicus community(V). The results of vegetation structure analysis, the forest of Dogabsa Valley area is a transition area of southern part of temperate forest and warm temperate forest zone. The forest is about 40-50-year-old.

Thermal and Dynamical Evolution of a Gaseous Medium and Star Formation in Disk Galaxies

  • Kim, Chang-Goo;Kim, Woong-Tae;Ostriker, Eve C.
    • The Bulletin of The Korean Astronomical Society
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    • v.36 no.1
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    • pp.54.1-54.1
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    • 2011
  • Formation of self-gravitating gas clouds and hence stars in galaxies is a consequence of both thermal and dynamical evolution of a gaseous medium. Using hydrodynamics simulations including cooling and heating explicitly, we follow simultaneously thermal and dynamical evolution of galactic gas disks to study dynamics and structures of galactic spiral shocks with thermal instability and regulation of the star formation rates (SFRs). We first perform one-dimensional simulations in direction perpendicular to spiral arms. The multiphase gas flows across the arm soon achieve a quasi-steady state characterized by transitions from warm to cold phases at the shock and from cold to warm phases in the postshock expansion zone, producing a substantial fraction of intermediate-temperature gas. Next, we allow a vertical degree of freedom to model vertically stratified disks. The shock front experiences unsteady flapping motions, driving a significant amount of random gas motions, and self-gravity promotes formation of bound clouds inside spiral arms. Finally, we include the star formation feedback in both mechanical (due to supernova explosion) and radiative (due to FUV heating by young stars) forms in the absence of spiral arms. At saturation, gravitationally bound clouds form via thermal and gravitational instabilities, which are compensated by disruption via supernova explosions. We find that the FUV heating regulates the SFRs when gas surface density is low, confirming the prediction of the thermal and dynamical equilibrium model of Ostriker et al. (2010) for star formation regulation.

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Paleoenvironmental Research Using Diatoms from Core Sediments in the Heuksan Mud belt, Korea (흑산 니질대 코어퇴적물에서 산출된 규조를 이용한 고환경 연구)

  • Bak, Young-Suk;Chang, Tae Soo
    • Journal of the Korean earth science society
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    • v.37 no.6
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    • pp.325-331
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    • 2016
  • Three diatom assemblage zones were erected from HMB-103 core sediment of the Heuksan Mud Belt. The paleoenvironmental changes were reconstructed basing on diatom analyses using indicator species, cold and warm water species, and salinity. Seventy-six species belonging to 41 genera were identified in the core sediments. The number of diatom valves per gram of dry sediment ranged from 0.1 to $15.4{\times}10^4g^{-1}$. As a result, diatom assemblage I in about 45,000 yr B.P showed a high abundance in cold species indicating a major influence by the Korea Coastal Current. Diatom assemblage II from 14,000 to 11,646 yr B.P is characterized by rare abundance and indicative of the cold periods at Younger Dryas with the lower sea-level. However, diatom assemblage III from 11,646 yr B.P to Holocene was more affected by the Yellow Sea Warm Current while the progressive sea level rise.

A Review of Vegetation Succession in Warm-Temperate Evergreen Broad-Leaved Forests -Focusing on Actinodaphne lancifolia Community- (난온대 상록활엽수림 지역의 식생천이계열 고찰 -육박나무군락을 중심으로-)

  • Park, Seok-Gon;Choi, Song-Hyun;Lee, Sang-Cheol
    • Korean Journal of Environment and Ecology
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    • v.32 no.1
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    • pp.77-96
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    • 2018
  • We investigated and analyzed three Korean island sites (Bijin-do, Ae-do, and Bogil-do) and one Japanese site (Tachibanayama) of sword-leaf litsea (Actinodaphne lancifolia) forests, known as the climax forest, to discuss the vegetation succession sere of warm-temperature evergreen broad-leaved forests. We then reviewed the literature in Korea, Japan, China, and Taiwan to consider the distribution characteristics of evergreen broad-leaved forests, vegetation succession sere, and climax tree species. Although Mt. Tachibana and Ae-do showed the most advanced vegetation structure, the soil and ordination (CCA) analysis indicated that it was not enough to consider that the sword-leaf litsea forest was at the climax stage in the warm-temperature region. The Actinodaphne lancifolia forest is sparsely distributed in Korea and Japan while the common types of vegetation in the warm temperate zone region in East Asia are Machilus spp., Castanopsis spp., and Cyclobalanopsis spp. The vegetation succession sere of the Korean warm-temperature region is thought to have a secondary succession such as Pinus thunbergii, P. densiflora, Q. serrata (early stage) through Machilus thunbergii, innamomum yabunikkei, Neolitsea sericea, Actinodaphne lancifolia (middle stage) to Castanopsis sieboldii, Q. acuta, Q. salicina (climax stage). However, Machilus thunbergii will be the climax species as an edaphic climax in places where there is a strong influence of the sea wind, or it is difficult to supply the seeds of Castanopsis spp. and Cyclobalanopsis spp.

Components of phytoncide from a pine forest in the southern temperate zone

  • Lee, Jeong Do;Park, Choong Hee;Joung, Da Wou;Koo, Seung Mo;Park, Bum Jin
    • Korean Journal of Agricultural Science
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    • v.46 no.1
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    • pp.33-44
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    • 2019
  • This study was conducted to examine the components of phytoncide from a pine forest in the southern temperate zone. Recent studies have found that a large amount of phytoncide is released not only from cypress trees but also from pine trees. Because the amount released is the highest during summer, we selected a warm climate region in the southern temperate zone and measured the concentration in the month of August. To capture the phytoncide from the forest atmosphere, we used the adsorption tube method with a mini pump and successfully gathered 9 L of forest air at a flow rate of 150 mL/min. We performed duplicate sampling from two different tubes installed at the same location and derived the mean value. A gas chromatography/mass spectrometer detector with thermal desorption spectroscopy was utilized to perform quantitative and qualitative analyses of the captured material. The results showed that the average phytoncide particle of the pine forest in the southern temperate zone contained a number of components as follows in descending order: ${\alpha}$-Pinene (39%, $0.28ng/m^3$), followed by ${\beta}$-Pinene (16%, $0.11ng/m^3$), D-Limonene (8%, $0.06ng/m^3$), camphor (6%, $0.04ng/m^3$), camphene (6%, $0.04ng/m^3$), and p-Cymene (5%, $0.04ng/m^3$). There were also 13 additional phytoncide components in trace amounts. The results of this study are expected to provide a useful dataset for building a "Healing-forest".

Phytocoenosen and Distribution of a Wild Tea (Camellia sinensis (L.) Kuntze) Population in South Korea (차나무 자생개체군의 식물사회와 분포 특이성)

  • Eom, Byeong-Cheol;Kim, Jong-Won
    • Korean Journal of Plant Resources
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    • v.30 no.2
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    • pp.176-190
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    • 2017
  • South Korea is the northernmost distributional territory on the Camellietea japonicae (evergreen broad-leaved forests of the warm-temperate zone) in East Asia. A total of 40 stands were collected in terms of an ecologically-naturalized wild tea population (WTP), and their species composition was analyzed by $Z{\ddot{u}}rich$-Montpellier School's method with preliminary regard to forest canopy idendtification. Stand types were characterized by ecological flora's criteria such as Raunkiaer's life-form, neophyte, zonal distribution, and nativeness of species. Expansion of WTP distribution into the interior of the peninsula was recognized, than expected. The highest and northernmost WTPs have been recorded at Mt. Palgong, Daegu (390 m a.s.l.) and Iksan Jeonbuk (latitude $36^{\circ}$ 03' 33''), respectively. Altitudinal and latitudinal WTP distribution of Korea under continental climate shows lower than Japanese situation under oceanic climate. Community structure generally involved a few human interferences. Syngeographically WTP distribution was limited on the warm-temperate zone and the southernmost cool-temperate southern submontane zone. First driving force on distributional expansion of the WTP was anthropogenic, particularly in the northernmost distribution area. We finally confirmed an actual existence of the WTP in South Korea and suggested a long-term monitoring on the WTPs in national view of in-situ genetic resources with higher frost-resistance.

Future Projections of Köppen Climate Shifts in the Asia Regions Using A2 Scenario (A2 시나리오를 이용한 아시아 지역 기후대의 변화 전망)

  • Shin, Sang Hoon;Bae, Deg Hyo
    • Journal of Korea Water Resources Association
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    • v.46 no.3
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    • pp.253-265
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    • 2013
  • The objective of this study is to analyse the current climate zone applied by K$\ddot{o}$ppen climate classification and the future climate zone projected by the A2 scenario in Asia regions. The spatial and temporal variations of precipitation and temperature were also analyzed. As regards to the result of analysis on the variation of climate factor, temperature and precipitation will be increasing $4.0^{\circ}C$ and 12% respectively in the 2080s comparing with the reference period (1991~2010). Spatially, the range of temperature increase on the high latitude area is higher than that on the low latitude area. The precipitation will be increasing averagely in the overall area, but the spatial unequal distribution of precipitation will be intensified. At the result of the future climate zone, the area of warm climates will be increasing while the area of cold climates will be decreasing. In 2080s, the temperature will be increasing as much as 7.2% and 1.9% on the Tropical climates and Arid climates respectively, but it will be decreasing as -2.4%, -4.9% and -1.8% on the Warm temperate climates, Cold climates and Polar climates respectively. Furthermore, the part of Savannah climates and Desert climates will be mostly increasing. It is mainly caused by the temperature increase and desertification impact according to global warming.

Pollen analysis of alpine wetlands on Mt. Jeombong in Gangwon-do, South Korea and climate change during the late Holocene (점봉산 고산습지의 화분분석과 홀로세 후기 기후변화)

  • Yoon, Soon-Ock;Kim, Minji;Hwang, Sangill
    • Journal of The Geomorphological Association of Korea
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    • v.20 no.4
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    • pp.101-115
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    • 2013
  • 11 alpine wetlands at the upper reaches of Bangtae River on a high flat summit around Mt. Jeombong were found. Two core samples(JB-1 and JB-2) among them were collected in order to reconstruct paleovegetation history and climate change using pollen analysis. Pinus and Quercus dominated at the wetland of JB-2 with a deep water depth were developed from 1,700 yr BP to 1,000 yr BP of the pollen zone I. Subsequently Quercus dominated in the pollen zone II from 1,000 to 400 yr BP, and it is supposed that warm weather prevailed with oak climax forest corresponding to the Medieval Warm Period. Moreover, sphagnum grew densely in the alpine wetlands and the wetlands were extended widely on the summit around Mt. Jeombong with the beginning of subzoneIIc at JB-2. The pollen zone III from 400 yr BP to the present with an increase in Pinus and a decrease in Quercus suggests cold climates under the Little Ice Age. Moreover, human disturbances at JB-2 were more significant than those at JB-1, based on the increase in Pinus.