• 제목/요약/키워드: the Physical Geography

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The formation and characteristics of loess sediments during the last glacial period in the Eonyang area, Ulsan-si, Korea (울산시 언양 지역 최종빙기 뢰스 형성과 퇴적물 특성)

  • YOON, Soon-Ock;PARK, Chung-Sun;HWANG, Sangill
    • Journal of The Geomorphological Association of Korea
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    • v.19 no.4
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    • pp.157-168
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    • 2012
  • The Eonyang section is located at the confluent area of Samdong River to Taehwa River in Sinhwa-ri, Samnam-myeon, Ulju-gun, Ulsan-si, Korea. Physical analyses such as the OSL age dating, magnetic susceptibility and grain size analysis were performed. Coarse grains in the upper section were deposited by the aeolian processes from the local sources and the grains in the lower section by the fluvial processes. The Eonyang section shows the large differences such as the irregularity in the variations of magnetic susceptibility, large deviations in the Y values and very poor sorting values from the loess sediments in Bongdong, Geochang and Daecheon in Korea. These characteristics in the Eonyang section suggest the multi-source areas such as the Chinese Loess Plateau and nearby floodplain or the influences by the other processes. The loess sediments of Eonyang section were formed during the period from the late MIS 3 to MIS 2.

Distribution of invasive alien plants on the islands of the Korean Peninsula based on flora data (식물상 자료에 기초한 한반도 도서 지역의 생태계 교란 외래식물 분포)

  • Kim, Hyun-Hee;Mizuno, Kazuharu;Kim, Da-Bin;Lee, Ho-Sang;Kong, Woo-Seok
    • Korean Journal of Environmental Biology
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    • v.38 no.3
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    • pp.392-403
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    • 2020
  • This study analyzed the distribution characteristics of invasive alien plants on the islands of the Korean Peninsula. Ten species, Rumex acetosella, Sicyos angulatus, Solanum carolinense, Ambrosia artemisiaefolia var. elatior, Ambrosia trifida, Aster pilosus, Eupatorium rugosum, Hypochaeris radicata, Lactuca scariola, and Paspalum distichum were present on 68 islands. These ecosystem-disturbing invasive alien plants appeared extensively on the islands of Gyeonggi province and Jeollanam province. The proportion of the plants on the inhabited islands (41 places, 2.15 species on average) was higher than that on the uninhabited islands (27 places, 1.07 species on average). This means that the distribution of invasive alien plants was closely related to human activity. The distribution of Ambrosia artemisiaefolia var. elatior(32 islands) and Rumex acetosella (31 islands) was the widest, and there were distinct distribution differences according to species. In the island area, the physical environment is poor compared to the mainland, and the native space is limited. Therefore, when invasive alien species enter and settle on the island, the native island plants can be damaged more than those on the mainland. In this regard, the discussion of the distribution of invasive alien plants in the island region can contribute to the conservation of biodiversity in the region.

The Evidence for the High Sea Level of MIS 5e and the Paleo-coastal Sediments from Sinji-myen, Wando-gun, Jeollanam-do, Korea (전남 완도군 신지면 일대의 고해안퇴적층과 최종간빙기 고해수면 증거)

  • Shin, Won Jeong;Lee, Jae Ho;Byun, Jongmin;Kim, Jong Yeon
    • Journal of The Geomorphological Association of Korea
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    • v.26 no.1
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    • pp.59-78
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    • 2019
  • The physical and chemical characteristics of more than 5 m sandy deposits behind the beach in Sinji-do Island are investigated and its burial ages are estimated using Optically Stimulated Luminescence. By the estimated burial ages of the sandy deposits, this section is divided into four sub-units: Unit I (6.2 ka), Unit II (23.2 ka), Unit III (115.9 ka), and Unit IV (115.9 to 127.5 ka). It can be proposed that the Unit I of a coarse sand deposited during the Holocene Climatic Optimum. Unit II, supposed to be the aeolian sediments, formed during the Last Glacial Maximum (LGM). It can be supposed that the study area was not affected by the marine processes during the LGM, directly. Unit III is more consolidated deposits of coarse silt to fine sand and deposited during the Last Interglacial Period. Unit IV mainly consist of beach gravels with sandy matrix deposited during the Marine Isotope Stage 5e (MIS 5e), and thus indicates that the sea level of the southwest sea had risen 3 to 5 m above present sea level during the MIS 5e.

Influences of Human Residence and Environmental Factors on Malaria Incidence in Korea (우리나라 말라리아 발생에 미치는 주거와 환경 요인의 영향에 대한 연구)

  • Park, Sunyurp;Kim, Juhye;Choi, Jinmu
    • Journal of the Korean association of regional geographers
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    • v.20 no.3
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    • pp.334-343
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    • 2014
  • The number of malaria cases has been undulating for the past 10 years in Korea since the reemergence of malaria in early 1990's. Considering the spatial variations of malaria incidence across the northmost border areas near the demilitarized zone (DMZ), the occurrence of the disease seems to be influenced by the natural and human environment in the region. Malaria is an infectious disease that is transmitted to humans by the bites of vector-mosquitoes that carry malaria parasites, and its incidence rate depends on specific climatic and sociodemographic factors. This study found that the spatial characteristics of malaria incidence have varied depending on relative proportions of mosquito habitats, distance between mosquito habitats and human residence, the physical and sociodemographic environments of the city by urbanization, and local topography.

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Development in Geomorphology and Soil Geography: Focusing on the Journal of the Korean Geomorphological Association (한국지형학회지를 중심으로 본 지형학과 토양지리학의 발달)

  • Park, Kyeong
    • Journal of the Korean Geographical Society
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    • v.47 no.4
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    • pp.474-489
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    • 2012
  • Last review papers on Korean geomorphology and physical geography had been published in 1997 and 2000 respectively. A proposal to publish a book on Korean geomorphologists' achievement resulted in series of review papers in Journal of the Korean Geomorphological Association. This article aims to summarize these papers and introduce their findings to foreign scholars. On remarkable achievement is a fierce debate on the effectiveness of traditional mountain concept to explain the shape of Korean peninsula, which made the public's understanding of geomorphology widen to the general public. Reflecting public demands, concerns for the effects of coastal facilities on coastal erosion and conservation mind and scientific researches for the coastal sand dunes have increased so much. Geomorphological hazards such as debris flow attracted many concerned scientists, and geotourism-related papers in scientific journals increased thanks to the designation of first geopark in Korea. Research papers submitted to the famous foreign academic journals are increasing in numbers these days.

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Sedimentary Characteristics and Chronology of Loess-paleosol Sequence in Jeongjang-ri, Geochang basin, Gyeongnam Province (경남 거창분지 정창리 뢰스-고토양 연속층의 퇴적물 특성과 편년)

  • Hwang, Sang-Ill;Kang, Chang-Hyeok;Yoon, Soon-Ock
    • Journal of the Korean Geographical Society
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    • v.46 no.1
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    • pp.1-19
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    • 2011
  • The physical and chemical characteristics of loess-paleosol sequence in Jeongjang-ri, Geochang basin are examined using the magnetic susceptibility measurement, grain size analysis, OSL age dating, major, rare earth and trace elements analysis. The grain size characteristics of the loess-palesol sequence are obviously different from those of river sediment forming river terrace deposits and the Chinese Loess Plateau. The loess-paleosol sequence consisting of L1, L1LL1, L1S1, L1L2, S1 and L2 from top to bottom is estimated to MIS 2~MIS 6 and the river terrace to MIS 7. The compositions of major, rare earth and trace elements indicate that the sequence show more weathered characteristics than the Chinese Loess Plateau and originated from the Chinese Loess Plateau. These features are in harmony with the previous studies in Korea.

A Study on Geographers Participation in the Pubic Sector: A Case of French Geographers (지리학자의 공공직 참여에 관한 연구: 프랑스 사례를 중심으로)

  • Lee Hyeongjoo;Kwon Yongwoo
    • Journal of the Korean Geographical Society
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    • v.39 no.4
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    • pp.683-695
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    • 2004
  • It is generally found that geography majors' progression in society has a very limited scope in Korea and this is one of the causes of lessening geographers' job market. As an attempt to draw a solution to this problem, this paper, by a close examination of the French case, tries to discuss the possibility of geographers' participation in the public sector. Geographers' participation in political and social issues has long history. They acted as providers of geographical knowledge on human and physical features of the world and also as counsellors for effective administration and politics. French geographers evaluate that it is the characteristics of geography that enable geographers to progress into the public sector. They also perceive that such fields as regional development, environment, economy, tourism, international politics are possible ones for geographers. Some implications can be drawn from this case study to extend geographers' participation in the pubic sector in Korea; it is required to sustain open mind to every field of social sciences, to improve specialized as well as generalized knowledge on geographical features, and to provide practical knowledge on spatial analysis and management.

Discussion about Characteristics and Study Results of Phytolith for the Quaternary Paleoenvironmental Reconstruction (제4기 환경복원을 위한 식물규소체의 특성과 연구 성과에 대한 논의)

  • HWANG, Sangill;KIM, Hyo-Seon;YOON, Soon-Ock
    • Journal of The Geomorphological Association of Korea
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    • v.17 no.3
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    • pp.1-16
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    • 2010
  • Phytoliths, silica microfossil that produced within and between cells and tissues of plants are especially yielded in Gramineae with many different forms and can attribute to the reconstruction of climatic and environmental changes and agriculture activity of the Quaternary. The phytoliths in soil can remain for long periods of time, because of strong resistance to physical and chemical weathering. The spatial range of study is too small due to deposition of phytoliths directly to the soil. There are difficulties of phytoliths identification because of multiplicity and redundancy, so far uniform and exact classification scheme has not been adopted. Therefore we attempted phytolith classification system applied to Korea. The paleoenvironmental reconstruction research using phytholith are applicated in many parts of studies. Also high-resolution paleoclimatic reconstruction expected to be possible using phytolith indices of Iph and Ic as well as climatic indicator of phytolith morphology.

Evaluation of Changesin the Physical Characteristics of Raindrops Under a Canopy in Central Korea (나무 아래 빗방울(雨滴)의 물리적 특성변화 분석)

  • Kim, Jin Kwan;Kim, Min Seok;Yang, Dong Yoon;Lim, Young Shin
    • Journal of The Geomorphological Association of Korea
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    • v.23 no.3
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    • pp.105-122
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    • 2016
  • To evaluate the changes in the physical characteristics of open rainfall related to canopy effects and rainfall intensity in Korea, the terminal velocity of raindrops and drop size distributions(DSD) were continuously measured by an optical-laser disdrometer in an open site(Op) and in two forest stands(Th1: Larix leptolepis, Th2: Pinus koraiensis) during five rainfall events in 2008. The terminal velocity, DSD and two forms of kinetic energy(KE, $Jm^{-2}$ $mm^{-1}$; KER, $Jm^{-2}$ $h^{-1}$) of open rainfall drops were determined and were compared with those of throughfall drops under two different canopy heights. The effects of the canopy and rainfall intensity, together with wind speed, on the changes in drop size and kinetic energy of throughfall were evaluated. Throughfall drops were larger than open rainfall drops. The distribution of terminal velocities for the drop sizes measured at Th2 was lower than that at Op; however, at Th1 the distribution was similar to that at Op. The total kinetic energy of throughfall at Th1 and Th2 was higher than the total kinetic energy of open rainfall, and the kinetic energy distribution for the drop sizes wassimilar to the drop size distribution. The observed throughfall-KER at Th1 was lower than an estimate previously produced using a model. The overestimation from the modeled value at Th1 was likely to be due to overestimated values of a square root transformation of fall height and its coefficient in the model because the distributions of terminal velocity for the drop size measured at Th1 were similar to those of open rainfall.

Interpretation of Physical Geographic Meaning of Village Names in Geoje City, South Korea (거제시 마을 이름에 대한 자연지리적 해석 -지형.기상.토양 관련 마을 이름을 중심으로-)

  • Gang, Hee-Soon;Beam, Seon-Gyu
    • Journal of the Korean association of regional geographers
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    • v.11 no.5
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    • pp.368-382
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    • 2005
  • This paper deals with the village names in Geoje City[Geoje Island], Hundreds of village names in the city are found to be based on some environmental features such as landforms, weather, and soil of the island. A considerable number of village names in the city are derived from the mountainous landforms with steep slopes or from the extremely indented coastlines with many small islands, and some village names are originated from the weather and soil. In this paper, it is realized that the village names often reflect the environments perception of the residents and that they can give some clues to the environment's changes of the places.

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