• Title/Summary/Keyword: Subtropical Area

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On the Subtropical Countercurrent in the Western North Pacific

  • Chang, Sun-duck
    • 한국해양학회지
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    • v.8 no.1
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    • pp.4-8
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    • 1973
  • Recent dynamic computations of zonal flow and analysis of oceanographic data of CSK in winter indicate year-to year variations in the location and dynmic structure of the Subtropic Countercurrent in the western North Pacific. In January 1966, the Subtropical Countercurrent migrated southward to 21$^{\circ}$- 22$^{\circ}$N Lat in association with the subsurface Subtropical Convergence. At the area of 25$^{\circ}$- 26$^{\circ}$N Lat, another surface thermal front was formed along which a stronger eastward flow of approximately 0.4kt is seen. On the section of 142$^{\circ}$E Long in January 1967, eastward flow appears at every interval of 2$^{\circ}$latitude in the northern waters of 20$^{\circ}$N Lat.

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Floristic study of bryophytes in a subtropical forest of Nabeup-ri at Aewol Gotjawal, Jejudo Island

  • YIM, Eun-Young;HYUN, Hwa-Ja
    • Korean Journal of Plant Taxonomy
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    • v.48 no.1
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    • pp.100-108
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    • 2018
  • This study presents a survey of bryophytes in a subtropical forest of Nabeup-ri, known as Geumsan Park, located at Aewol Gotjawal in the northwestern part of Jejudo Island, Korea. A total of 63 taxa belonging to Bryophyta (22 families 37 genera 44 species), Marchantiophyta (7 families 11 genera 18 species), and Anthocerotophyta (1 family 1 genus 1 species) were determined, and the liverwort index was 30.2%. The predominant life form was the mat form. The rates of bryophytes dominating in mesic to hygric sites were higher than the bryophytes mainly observed in xeric habitats. These values indicate that such forests are widespread in this study area. Moreover, the rock was the substrate type, which plays a major role in providing micro-habitats for bryophytes. We suggest that more detailed studies of the bryophyte flora should be conducted on a regional scale to provide basic data for selecting indicator species of Gotjawal and evergreen broad-leaved forests on Jejudo Island.

Recent developments in biotechnological improvement of Zoysia japonica Steud. (형질전환 들잔디 개발의 최근 동향)

  • Sun, Hyeon-Jin;Song, In-Ja;Bae, Tae-Woong;Lee, Hyo-Yeon
    • Journal of Plant Biotechnology
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    • v.37 no.4
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    • pp.400-407
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    • 2010
  • Zoysiagrass (Zoysia japonica Steud.), also called Korean or Japanese lawngrass, is the most popular warm-season turfgrass in Korea and is widely used for home lawns, parks, roadsides, golf courses and athletic fields. Its use is rapidly expanding in Korea and the other countries, due to its excellent characteristics which include tolerance to heat, drought and salinity. As the utilization area of this turfgrass increases, there is an increase in the demand for improved cultivars with disease and insect tolerance or with herbicide-tolerance or with extended greening periods. Conventional breeding methods have been used to improve the traits described above with limited success. However, with the advances in biotechnology, genetic transformation can be utilized for turfgrass improvement. In this paper, we review recent progress in biotechnological improvement of zoysiagrass and discuss future molecular breeding of this species.

Association Between MSTN Gene Polymorphism and Growth Traits in Landrace Pigs (돼지 Landrace 품종에서 Myostatin 유전자의 유전적 다형성과 성장형질과의 연관성)

  • Cho, I.C.;Choi, Y.L.;Ko, M.S.;Kim, H.S.;Lee, J.G.;Jeon, J.T.;Han, Sang-Hyun
    • Journal of Animal Science and Technology
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    • v.47 no.2
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    • pp.159-166
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    • 2005
  • Porcine myostatin(MS1N) gene plays a key role in the differentiation of myoblast and muscle development. Genetic polymorphism was screened by single stranded conformation polymorphism(SSCP) analysis and subsequent DNA sequencing detected a nucleotide substitution(C2150T) in exon 3 of MSIN gene. Phenotypic association of the polymorphism was tested in a Landrace population and positive effects of the allele T for lean growth traits were found in the population. Even though it is not significant, the pigs have IT and TC genotypes were heavier for the body weight at birth and at twenty weeks of age than those containing genotype. Cc. However, the allele T was significantly associated with higher eye muscle area(P < 0.05). As a result of this study, we suggested that the allele T in exon 3 of MSTN gene comes a significant effect for increasing the eye muscle area without decreasing backfat thickness. This polymorphism did not change the amino acid but Taq I -RFLP matched to SSCP band patterns in exon 3 of MSTN gene, which will be an useful molecular marker for breeding of Landrace pigs.

Current Situations and Prospects on the Cultivation Program of Tropical and Subtropical Crops in Korea (국외 도입 열대·아열대 작물의 국내 재배실태 및 과제)

  • Kim, Chang-Yung;Kim, Young-Ho;Han, Sin-Hee;Ko, Ho-Cheol
    • Korean Journal of Plant Resources
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    • v.32 no.1
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    • pp.45-52
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    • 2019
  • In the process of adapting climate change, the government needs to provide policy and technical support necessary for growing promising crops imported from abroad. Therefore, this study was conducted to survey and analyze the conditions of growth of imported foreign crops and to derive response tasks. As a result, tropical and subtropical vegetables were cultivated 18 crops in 920 farms in 321 ha area (in 2015 year). The cultivation scale decreased in the order of Curcuma aromatica, Momordica charantia, Asparagus aethiopicus, Allium hookeri and Herbs. Tropical and subtropical fruits were cultivated 9 crops in 264 farms in 106.5 ha area (in 2015 year). Special and medicinal crops introduced abroad cultivated 10 crops in 753 farms in 276.3 ha area (in 2015 year). The cultivation scale decreased in the order of Curcuma longa, Glycyrrhiza uralensis, Lepidium meyenii and Moringa oleifera. For the stable settlement of domestic growth of tropical and subtropical crops introduced abroad, there should be safety and economic feasibility in terms of the cultivation environment according to the domestic culture adaptation test. Consideration needs to be given to the use of locally grown products in Korea, the securing of distribution and sales markets, and the competitiveness of imported products.

Prediction of Changes in Potential Distribution of Warm-Temperate and Subtropical Trees, Myrica rubra and Syzygium buxifolium in South Korea (남한에서 기후변화에 따른 난아열대 목본식물, Myrica rubra와 Syzygium buxifolium의 잠재분포 변화 예측)

  • Eun-Young, Yim;Hyun-kyu, Won;Jong-Seo, Won;Dana, Kim;Hyungjin, Cho
    • Ecology and Resilient Infrastructure
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    • v.9 no.4
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    • pp.282-289
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    • 2022
  • Analyzing the impact of climate change on the Korean Peninsula on the forest ecosystem is important for the management of subtropical forest bioresources. In this study, we collected location data and bioclimatic variables of the warm-temperate woody plant species, Myrica rubra and Cyzygium buxifolium, and applied the MaxEnt model based on the collected data to estimate the potential distribution area. Precipitation and temperature seasonality in the warmest quarter were the main environmental factors that determined the distribution of M. rubra, and the main environmental factors for S. buxifolium were precipitation in the warmest quarter and precipitation in the wettest quarter. The results of the MaxEnt model by administrative district, the M. rubra showed an area increase rate of 4.6 - 17.7% in the SSP2-4.5 climate change scenario and 13.8 - 30.5% in the SSP5-8.5 climate change scenario. S. buxifolium showed area increase rates of 4.8 - 32.2% in the SSP2-4.5 climate change scenario and 12.9 - 48.6% in the SSP5-8.5 climate change scenario. This study is meaningful in establishing a database and identifying future potential distribution areas of warm and subtropical plants by applying climate change scenarios.

Vegetation structure and distribution characteristics of Symplocos prunifolia, a rare evergreen broad-leaved tree in Korea

  • Kim, Yangji;Song, Kukman;Yim, Eunyoung;Seo, Yeonok;Choi, Hyungsoon;Choi, Byoungki
    • Journal of Ecology and Environment
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    • v.44 no.4
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    • pp.275-285
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    • 2020
  • Background: In Korea, Symplocos prunifolia Siebold. & Zucc. is only found on Jeju Island. Conservation of the species is difficult because little is known about its distribution and natural habitat. The lack of research and survey data on the characteristics of native vegetation and distribution of this species means that there is insufficient information to guide the management and conservation of this species and related vegetation. Therefore, this study aims to identify the distribution and vegetation associated with S. prunifolia. Results: As a result of field investigations, it was confirmed that the native S. prunifolia communities were distributed in 4 areas located on the southern side of Mt. Halla and within the evergreen broad-leaved forest zones. Furthermore, these evergreen broad-leaved forest zones are themselves located in the warm temperate zone which are distributed along the valley sides at elevations between 318 and 461 m. S. prunifolia was only found on the south side of Mt. Halla, and mainly on south-facing slopes; however, small communities were found to be growing on northwest-facing slopes. It has been confirmed that S. prunifolia trees are rare but an important constituent species in the evergreen broad-leaved forest of Jeju. The mean importance percentage of S. prunifolia community was 48.84 for Castanopsis sieboldii, 17.79 for Quercus acuta, and 12.12 for Pinus thunbergii; S. prunifolia was the ninth most important species (2.6). Conclusions: S. prunifolia can be found growing along the natural streams of Jeju, where there is little anthropogenic influence and where the streams have caused soil disturbance through natural processes of erosion and deposition of sediments. Currently, the native area of S. prunifolia is about 3300 ㎡, which contains a confirmed population of 180 individual plants. As a result of these low population sizes, it places it in the category of an extremely endangered plant in Korea. In some native sites, the canopy of evergreen broad-leaved forest formed, but the frequency and coverage of species were not high. Negative factors that contributed to the low distribution of this species were factors such as lacking in shade tolerance, low fruiting rates, small native areas, and special habitats as well as requiring adequate stream disturbance. Presently, due to changes in climate, it is unclear whether this species will see an increase in its population and habitat area or whether it will remain as an endangered species within Korea. What is clear, however, is that the preservation of the present native habitats and population is extremely important if the population is to be maintained and expanded. It is also meaningful in terms of the stable conservation of biodiversity in Korea. Therefore, based on the results of this study, it is judged that a systematic evaluation for the preservation and conservation of the habitat and vegetation management method of S. prunifolia should be conducted.

Development of distinction methods for male-sterile and dwarfism herbicide tolerant Zoysia japonica Steud (웅성불임 및 왜성형질의 제초제저항성 들잔디(zoysia japonica Steud.)의 판별기술 개발)

  • Lee, Bum Kyu;Kang, Hong-Gyu;Ra, Nu Ri;Sun, Hyeon-Jin;Kwon, Yong-Ik;Song, In-Ja;Kim, Chang-Gi;Ryu, Tae-Hun;Park, Kee Woong;Lee, Hyo-Yeon
    • Korean Journal of Agricultural Science
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    • v.41 no.3
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    • pp.187-191
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    • 2014
  • The cultivation area and use of genetically modified (GM) crops have been increased continuously over the world. Concerns about the potential risks of GM crops are also increasing. Safe management for the development and production of GM crops is required according to Living Modified Organism Act in Korea. Planning about the methods, duration, and frequency of environmental monitoring is also required for commercial use of GM crops. GM Zoysia japonica Steud. (event name: JG21) expressing resistance to glufosinate-ammonium has been generated previously. By using gamma ray treatment to JG21 we also developed male sterility and dwarf Z. japonica (event name: JG21-MS). The objective of this study was to establish the monitoring system for environment release of JG21-MS. In this study we extracted RNA from JG21 and JG21-MS and conducted RAPD (random amplified polymorphic DNA) method to distinguish JG21 and JG21-MS.

Variation of Nutrients due to Long-Term Effects of Ocean Dumping and Spatial Variability of Water Quality Parameters in Summer at the Ocean Waste Disposal Site Off the West Coast of Korea (한국 서해 폐기물 투기해역의 하계 수질인자 분포특성과 장기 투기행위로 인한 영양염 농도 변화)

  • Koh, Hyuk Joon;Choi, Young Chan;Park, Sung Eun;Cha, Hyung Kee;Chang, Dae Soo;Yoon, Han Sam;Lee, Chung Il
    • Journal of Environmental Science International
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    • v.22 no.11
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    • pp.1389-1402
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    • 2013
  • This paper focuses on the impacts of waste dumping on inorganic nutrients in the dumping area of the Yellow Sea, and the effect of an governmental regulation of pollution in dumping areas. The environmental variables and parameters of the dumping and reference areas in the Yellow Sea were measured during July 2009 and analyzed. In addition, the analyzed data for inorganic nutrients over the last 10 years were obtained from the Korea Coast Guard (KCG) and the National Fisheries Research and Development Institute (NFRDI). The chemical environment of the study area revealed increases in concentrations of inorganic nutrients, Chemical Oxygen Demand (COD), and Volatile Suspended Solids (VSS) in the bottom layer. On the contrary, the pH level was decreased. Most notably, the time series data of inorganic nutrients showed gradual increase over time in the dumping area, and thus, the oligotrophic waters trend toward eutrophic waters. The increases appears to be due to the disposal of large amounts of organic waste. In recent times, the wastes disposed at the area were largely comprised of livestock wastewater, and food processing waste water. The liquefied waste, which contains an abundance of nutrients, causes a sharp increase in concentrations of inorganic nitrogen in the dumping area. On the one hand, the dumping sites have been deteriorated to such an extent that pollution has become a social problem. Consequentially, the government had a regulatory policy for improvement of marine environmental since 2007 in the dumping area. Hence, the quality of marine water in the dumping site has improved.

Evaluating the Ecological Characteristic and the Relative Significance for Forest Resources Management on the Uninhabitable Islands in Jeju Special Self-Governing Province (제주도 부속 무인도서의 산림자원관리를 위한 자연환경 특성과 상대적 중요도 평가)

  • Won, Hyun-Kyu;Jung, Sung-Cheol;Kim, Eun-Mi;Seo, Yeon-Ok;Kwon, Jin-O;Choa, Jong-Heon
    • Journal of Korean Society of Forest Science
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    • v.103 no.4
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    • pp.599-604
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    • 2014
  • This study was conducted to analyze the ecological environment of the 53 uninhabitable islands of Jeju for the management formulation. The result of the Pearson correlation analysis were 0.647(p<0.01) for herbs, 0.585(p<0.01) for trees and 0.762 (p<0.01) for animals which means that there is a high correlation between the size of the forests in the uninhabitable islands and the species diversity of herbs, trees and animals. For the regression modeling to predict the forest area, the R value was 0.899 and the $R^2$ was 0.803 with 79.7% statistical significance. This study also classified the uninhabited islands based on its forest area into two classes, with a forests area of 0.5ha and with a forest of approximately 12ha. The importance value of the biodiversity in the uninhabited islands was also evaluated using DEA and the islands with higher importance, namely DMU14(0.941), DMU36(0.964), DMU44(1.000) and DMU45(0.903) were recommended to be managed. It was observed that uninhabited islands with forests had a mean importance value of 0.439 which is higher as compared to the uninhabited islands without forests with 0.096. This verified that there is close relationship between forest and biodiversity.