• Title/Summary/Keyword: Jeju-island

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Occurrence characteristics and management plans of an ecosystem-disturbing plant, Hypochaeris radicata (생태계교란 식물인 서양금혼초의 발생특성과 관리방안)

  • In-Yong Lee;Seung-Hwan Kim;Yong-Ho Lee;Sun-Hee Hong
    • Korean Journal of Environmental Biology
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    • v.41 no.3
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    • pp.273-282
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    • 2023
  • Hypochaeris radicata, native to Europe and Eurasia, is a perennial plant of the Asteraceae family. In Korea, H. radicata was reported in 1992, mainly in Jeju Island, and gradually spreading to the inland. It overwinters in the form of a rosette and blooms yellow flowers from May to June. H. radicata propagates by seeds and rhizomes. The germination temperature of the seed is 15/20℃ (day/night), and the rhizome forms a new plant at a depth of 2-3cm in the soil. The roots of H. radicata secrete allelochemicals that inhibit the development of other plants. Some use it as a salad or forage substitute but to a limited extent. However, extensive research on ampicillin contained in H. radicata has been conducted, and its anticancer and anti-inflammatory effects have been recognized. There are only a few methods to manage H. radicata both culturally and physically. In orchards, soil treatments such as oxyfluorfen and diclobenil, or nonselective foliar treatments such as glufosinate-ammonium and glyphosate are used. Notably, there are no known biological control agents.

Submarine Discharge of Fresh Groundwater Through the Coastal Area of Korea Peninsula: Importance as a Future Water Resource (한반도 주변 연안 해저를 통한 담지하수의 유출: 미래 수자원으로서의 중요성)

  • Hwang, Dong-Woon;Kim, Gue-Buem;Lee, Jae-Young
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.15 no.4
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    • pp.192-202
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    • 2010
  • Submarine groundwater discharge (SGD) has been recognized as a provider for freshwater, nutrients, and dissolved constituents from continents to the oceans and paid more attention with regard to the mass balance of water or dissolved constituents on local and global scales. The submarine discharge of fresh groundwater (fresh SGD) through seepage or springs in coastal ocean may be especially important in aspects of water resource and marine environment managements in the future. Based on the worldwide compilations of observed fresh SGD, our review reveals that fresh SGD occurs in various marine environments along most shoreline of the world and the global estimates of fresh SGD were approximately 0.01-17% of surface runoff. In addition, the input of fresh SGD calculated and investigated in this study were about 50%, 57%, 89%, and 420% of total river discharge in Jeju Island, Yeongil Bay, Masan Bay, and Yeoja Bay, respectively. These inputs from fresh SGD along the shoreline of Korea Peninsula are much higher than those of the whole world, greatly vary with the region. However, since these estimates are based on the water balance method mainly used in coastal ocean, we have to perform continuous monitoring of various parameters, such as precipitation, tide, evapotanspiration and water residence time, which have an impact on the water balance in a lot of areas for evaluating the precise input of fresh SGD. In addition, since the method estimating the input of fresh SGD has brought up many problems, it is required to make an intercomparison between various methods such as hydrogeological assumption, numerical modeling, and seepage meter.

The Korean Peninsula Warming Based on Appearance Trend of Tropical Dinoflagellate Species, Genus Ornithocercus (열대 해역 지표종 Ornithocercus 속 와편모조의 출현 동향으로 본 한반도 온난화)

  • Kim, Hyeung-Sin;Jung, Min-Min;Lee, Joon-Baek
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.13 no.4
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    • pp.303-307
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    • 2008
  • We investigated about change of dinoflagellate composition during October 2006 to November 2007 at the Chagwi-Do, west-part of Jeju Island. There were 32 dinoflagellate species in collected samples and 19 species Amphisolenia bidentata, Ceratium gravidum, C. hexacanthum, C. platycorne, C. praelongum, C. ranipes, C. reflexum, C. geniculatum, Dissodinium elegans, D. bicorne, Ornithocercus heteroporus, O. magnificus, O. quadratus, O. splendidus, O. steinii, Protoperidinium excentricum, Pseliodinium vaubanii, Ptychodiscus noctiluca, Pyrocystis hamulus of collected dinoflagellate species were rare and unrecorded species from around the Korean Peninsula. The quantities by month of these tropical oceanic species, Ornithocercus were 28, 22, 0, 3 and $502\;cells/m^3$ in October 2006, February, April, September and November 2007 respectively. The abundance of genus Ornithocercus for whole dinoflagellate species were 8, 3.9, 0, 0.2 and 97.9% respectively. These results suggest that the coast of Korean Peninsula is getting warm by global warming.

Anti-inflammatory, Anti-aging, and Sebum Inhibitory Effects of Osmanthus fragrans Flower Extract (목서 꽃 추출물의 항염, 항노화 및 피지 억제 효능)

  • Hyung-Min Kim;Yeon Su Jeong;Sehyun Kim;Jeong Hun Cho;Yong Deog Hong;Won-Seok Park
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.50 no.2
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    • pp.171-178
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    • 2024
  • In this study, we aimed to determine the various effects of Osmanthus fragrans (O. fragrans) flower extract on the skin in order to utilize it as a cosmetic material. For this purpose, Osmanthus fragrans flower extract (OFFE) of Jeju Island was prepared and used in the experiment. The experiments were evaluated by the quantitative real-time polymerase chain reaction (qRT-PCR) and lipid droplet staining assay. First, the OFFE decreased the gene expressions of three representative pro-inflammatory cytokines (IL-8, IL-6, and IL-1α) and an inflammation-related enzyme, PTGS2 induced by poly I:C in epidermal keratinocytes. In addition, the OFFE increased the gene expression levels of collagen (COL1A1) and elastin (ELN) in dermal fibroblasts. Further, the OFFE showed the inhibitory effect in sebum production by linoleic acid in sebocytes. Therefore, from this study, it is expected that OFFE can be used as a natural cosmetic material for anti-inflammatory, anti-aging, and sebum inhibitory efficacy.

Using Fuzzy Set-Quality Comparative Analysis (fsQCA) to Explore the Factors Influencing on the Hindrance to Tourist Resident's Quality of Life (퍼지셋 질적 비교 분석(fsQCA)을 활용한 관광지 거주민들의 삶의 질 저하에 영향을 미치는 요인 연구 )

  • Hyunae Lee;Hee Chung Chung;Juyeon Ham;Namho Chung
    • Information Systems Review
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    • v.21 no.1
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    • pp.113-133
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    • 2019
  • Gentrification, caused by residents who are being forced out due to the rise of rent with vitalization by an excessive increase of city tourists and Touristification, meaning of phenomenon of residents' migration caused by residential area turning into tourist attraction have recently pointed out as a global problem. In Korea, the phenomenon such as environmental pollution, the rise of land value and rent, and the weakening of community culture in Jeju island and Bukchon Hanok Village has appeared as well. This phenomenon has become a serious problem by hindering resident's quality of life. In this circumstance, Smart tourism city has been regarded as a solution of these problems. Hence, this study chose Busan city, which has been designated as a smart city since 2015, and examined the complex impacts of the economic benefits, social costs, environmental substantiality, cultural benefits, and technical effects derived from tourism development on the residents' deteriorated quality of life based on Fuzzy-set Qualitative Analysis (fsQCA). As a result, three patterns of the hindrance to residents' quality of life were derived. If social costs of tourism development are perceived to be large, the residents perceive deteriorated quality of life, even if they recognize essential benefits (technological and economic benefits) (Pattern #1) or secondary benefits (environmental and cultural benefits) (Pattern #2) of tourism development. In addition, some residents were found not to recognize any benefits of tourism development (Pattern #3).

Anti-inflammatory effects of Lycoris chejuensis callus using biorenovation (Biorenovation 기법 적용 제주상사화 callus의 항염증 활성)

  • Hyehyun Hong;Tae-Jin Park;Yu-Jung Lee;Jung-Hwan Kim;Seung-Young Kim
    • Journal of Applied Biological Chemistry
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    • v.66
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    • pp.197-203
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    • 2023
  • Callus cultivation is a method for producing a large amount of tissue of a plant in the laboratory, regardless of the environment. Lycoris chejuensis, a plant species native to jeju island, is a member of the Lycoris family has been used as a traditional medicine for the treatment of diverse diseases. In this study, we evaluated anti-inflammatory effect of biorenovated Lycoris chejuensis callus (LCB) in lipopolysaccharide (LPS)-induced RAW264.7 cells. As a result, LCB was less toxic to the cells in the concentration range of 25, 50, and 100 ㎍/mL as shown by the improved viability of LCB treated cells than compared to Lycoris chejuensis callus (LC) treatment. In addition, LCB inhibited the generation of NO and prostaglandin E2 through the suppression of inducible nitric oxide synthase and cyclooxygenase-2 protein expression. LCB also attenuated the expression of interleukin-1β, interleukin-6 and tumor necrosis factor-α induced by LPS. The results suggest that LCB has anti-inflammatory activity on the LPS-induced inflammatory response and may be suitable for the development of potent functional cosmetic material.

Scientific Objectives and Mission Design of Ionospheric Anomaly Monitoring by Magnetometer And Plasma-Probe (IAMMAP) for a Sounding Rocket in Low-Altitude Ionosphere (저고도 전리권 관측을 위한 사운딩 로켓 실험용 IAMMAP(Ionospheric Anomaly Monitoring by Magnetometer And Plasma-Probe)의 과학적 목표와 임무 설계)

  • Jimin Hong;Yoon Shin;Sebum Chun;Sangwoo Youk;Jinkyu Kim;Wonho Cha;Seongog Park;Seunguk Lee;Suhwan Park;Jeong-Heon Kim;Kwangsun Ryu
    • Journal of Space Technology and Applications
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    • v.4 no.2
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    • pp.153-168
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    • 2024
  • Sounding rockets are cost-effective and rapidly deployable tools for directly exploring the ionosphere and microgravity environments. These rockets achieve their target altitudes quickly and are equipped with various scientific instruments to collect real-time data. Perigee Aerospace plans its inaugural test launch in the first half of 2024, followed by a second performance test launch in January 2025. The second launch, scheduled off the coast of Jeju Island, aims to reach an altitude of approximately 150 km with a payload of 30 kg, conducting various experiments in the suborbital region. Particularly in mid-latitude regions, the ionosphere sporadically exhibits increased electron densities in the sporadic E layers and magnetic fluctuations caused by the equatorial electrojet. To measure these phenomena, the sounding rocket version of ionospheric anomaly monitoring by magnetometer and plasma-probe (IAMMAP), currently under development at the KAIST Satellite Research Center, will be onboard. This study focuses on enhancing our understanding of the mid-latitude ionosphere and designing observable missions for the forthcoming performance tests.

Leaf gas exchange of Hibiscus hamabo and soil respiration in its habitats on Jeju Island (제주도 황근(Hibiscus hamabo) 잎의 기체 교환과 자생지에서의 토양호흡)

  • Yoojin Choi;Gwang-Jung Kim;Jeongmin Lee;Hyung-Sub Kim;Yowhan Son
    • Korean Journal of Environmental Biology
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    • v.41 no.4
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    • pp.439-446
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    • 2023
  • Mangroves are distributed in intertidal zones of coastal environments or estuarine margins, playing a critical role in the global carbon cycle. However, understanding of the carbon cycle role of mangrove associates in the Republic of Korea is still limited. This research measured soil respiration and leaf gas exchange in three habitats of Hibiscus hamabo(Gimnyeong, Seongsan, and Wimi) and analyzed the impacts on sites and months. Soil respiration was measured once a month from June to October 2022 and leaf gas exchange was measured monthly from June to September 2022. Soil respiration in August(5.7±0.8 μmol CO2 m-2 s-1) was significantly higher than that in other months (p<0.001) and soil respiration increased as air temperature increased (p<0.001). In Seongsan, net photosynthesis in July(9.0±0.9μmol m-2 s-1) was significantly higher than that in other months (p<0.001). Net photosynthesis increased as stomatal conductance and transpiration rate increased during the entire period(p<0.001). Furthermore, a weak positive linear relationship was observed between soil respiration and net photosynthesis (r2=0.12; p<0.01). The results indicated that soil respiration was influenced not only by air temperature and season but also by net photosynthesis. This study is expected to provide basic information on the carbon dynamics of mangrove associates.

Effect of Sand Particle Sizes on Turf Vegetation of Creeping Bentgrass (모래입경이 Creeping Bentgrass 잔디 초지의 식생에 미치는 영향)

  • Park Sung-Jun;Cho Nam-Ki;Kang Young-Kil;Song Chang-Khil;Cho Young-Il
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.25 no.3
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    • pp.205-210
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    • 2005
  • This study was conducted from March 21 to July 9 in 2004 at JeJu Island to investigate the effect of different particle sizes (0.3-0.5, 0.5-0.8, 0.8-1.0, 1.0-1.5 and 1.5-2.0mm) on creeping bentgrass vegetation. The results obtained were summarized as follows; plant height became shorter as particle size was increased from 0.3-0.5 to 1.5-2.0 n. Root length, Minolta SPAD-502 chlorophyll reading value, leave and root weight were directly proportional plant height response. Degree of land cover and density of creeping bentgrass decreased as the particle size was increased from 0.3-0.5 to 1.5-2.0nm, and degree land cover and density of weed increased. The number of weed species were increased as the sand particle size was increased. Then ranking of the dominant weeds were Portulaca oleracea, Trifolium repens and Cyperus amuricus (at 0.3-0.5 and 0.5-0.8mm particle size), Trifolium repens, Portulaca oleracea and Polygonum hydropiper (at 0.8-1.0mm particle size), Portulaca oleracea, Polygonum hydropiper and Poa annua (at 1.5-2.0mm particle size). Based on the these findings, the optimum sand particle size for growth of creeping bentgrass seems to be about 0.3-0.5m in volcanic ash soils of Jeju island.

Aboveground biomass estimation of Quercus glauca in evergreen forest, Kotzawal wetland, Cheju Island, Korea (제주도 곶자왈 상록활엽수 종가시나무의 생물량 추정을 위한 상대생장식)

  • Jeong, Heon-Mo;Kim, Hae-Ran;Cho, Kyu-Tae;Lee, Seung-Hyuk;Han, Young-Sub;You, Young-Han
    • Journal of Wetlands Research
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    • v.16 no.2
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    • pp.245-250
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    • 2014
  • This study developed allometry equation and estimated the aboveground-biomass of Quercus glauca, a warm-temperature, evergreen broad-leaved tree, growing in Kotzawal wetland located on Jeju Island. The allometric equations between DBH(diameter at breast height) and dry weights of stems (Ws), branches (Wb), leaves (Wl) and aboveground biomass (Wab) of Q. glauca were as follows: logWs=2.4042logDBH-1.3045, logWb=2.6436logDBH-1.6232, logWl =1.5428logDBH-1.3692 and logWab=2.3324logDBH-0.9181. The allometric equations between $D^2H$ and Ws, Wb, Wl, and Wab of Q.glauca were as follows : logWs=$0.853logD^2H-1.4252$, logWb=$0.8453logD^2H-1.5834$, logWl=$0.5328logD^2H-1.4073$ and logWab=$0.8453logD^2H-1.0327$. The $R^2$ between DBH and Ws, Wb, Wl and Wab were 0.9873, 0.9711, 0.7979 and 0.993, respectively. The $R^2$ between $D^2H$ and Ws,Wb,Wl and Wab were 0.9841, 0.9174, 0.7537 and 0.9876, respectively. There was no significant difference between observed and calculated values of the allomatric equations from DBH and $D^2H$(p>0.05, Kolmogorov-Smirnov test). Thus, to estimate the aboveground biomass of Q. glauca, use of DBH and $D^2H$ as an independent variables in the allometric equation is recommended.