• Korean Journal of Plant Resources
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• v.34 no.6
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• pp.616-632
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• 2021

We performed taxonomic reviews and habitat circumstances survey for 41 un-introduced environmentally harmful plants (as designated by the Ministry of Environment, Korea in 2016). And we investigated plant specimens from several herbaria and performed a field survey in the southeastern region of the United States. Based on the result, we presented the most comprehensive results of weed risk evaluation and taxonomic description up to now as well as classification keys for 11 species to apply the regulation management of putative invasive alien species - Senecio madagascariensis Poir., Sphagneticola trilobata (L.) Pruski, Ageratina riparia (Regel) R.M. King & H. Rob. (Asteraceae), Andropogon gayanus Kunth (Poaceae), Echinocystis lobata (Michx.) Torr. & A. Gray (Cucurbitaceae), Salvinia minima Baker (Salviniaceae), Vincetoxicum rossicum (Kleopow) Barbar. (Asclepiadaceae), Asparagus asparagoides (L.) Druce (Asparagaceae), Alternanthera pungens Kunth (Amaranthaceae), Salpichroa origanifolia (Lam.) Thell., and Lycium ferocissimum Miers (Solanaceae).

• Journal of Environmental Science International
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• v.20 no.9
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• pp.1191-1203
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• 2011

In case of Typhoon Dianmu, the temperature, wind speed, wind direction and the rainfall per hour changed dramatically when the center of the typhoon passed through Gimhae. Such a change was commonly found in the regions where the center of the typhoon passed through but almost not in the regions far away from it. For example, in the case of Typhoon Malou where the center of the typhoon was far away from the observation site, such a phenomenon was not observed. The analysis of the vertical observation data showed that there was a little change in the wind speed and wind direction in the vertical direction in the case of Typhoon Dianmu of which center passed through Gimhae. There was a great change in the wind speed according to the height in the lower atmosphere just before the center of the typhoon approached the region. When the center of the typhoon was passing through the region, the vertical wind speed was decreased. However, the wind speed was rapidly increased again after the center of the typhoon had passed through the region. Unlike the Dianmu, the difference in the wind speed and wind direction between the upper layer and lower layer of the atmosphere was relatively great in the case of Malou.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.5
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• pp.626-637
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• 2013

We measured the grain size, ignition loss (IL), chemical oxygen demand (COD), acid volatile sulfide (AVS) and trace metals (Al, Fe, Cu, Pb, Zn, Cd, Cr, Mn, Hg, and As) of intertidal surface sediment collected from 11 islands (62 stations) in the southern region of Jeollanam Province. The objective of this research was to evaluate the organic matter and trace metals contaminations of sediments from coastal island tidal flats. Surface sediment texture was characterized as follows: mud, sandy silt, muddy sand, and slightly gravelly sand facies. The finer sediments are mainly dominated in the northern part of each island. The concentrations of IL, COD, AVS and some trace metals (Al, Fe, Zn, Cr, Cu, and Hg) were higher in the northwestern part of Wan Island and the area between Gogeum and Sinji Islands, and were associated with relatively finer sediment, as compared to other locations. The concentrations of Mn, Pb, Cd, and As were higher in the northwestern and southeastern parts of Geoguem and Pyungil Islands, but were not correlated with mean grain size. Based on sediment quality guidelines (SQGs), the concentrations of trace metals were lower than the values of effect range low (ERL), used in United States, and threshold effects level (TEL), used in Korea, with exception of As. Similarly, the intertidal sediments were moderately contaminated with As, based on the the enrichment factor (EF) and the geoaccumulation index ($I_{geo}$). The high concentration of As in intertidal sediments from this study region may be due to the input of naturally or artificially contaminated submarine groundwater, contaminated waste from seaweed aquaculture operations and/or land-based seaweed processing facilities. Further studies are needed to identify the sources of As in this study region, and to determine the effects of As contamination on coastal ecosystem.

• Economic and Environmental Geology
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• v.39 no.4 s.179
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• pp.507-524
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• 2006

3-D seismic tomographic inversion is applied to investigation on velocity structure in and near Korean Peninsula. Firstly, it is applied to the region in southeastern Korean Peninsula. According to the results low-velocity zone seems to be clearly appeared in the so called Gyeongsang sedimentary basin and high-velocity zone is shown at the section of 7.5 km depth it implies the inclusion of plutonic rocks at the sedimentary basin. At the depth about $20{\sim}30$ km existence of low-velocity zone seems to be related with the development of Yangsan fault system. Secondly it is applied to the region not only in Korean Peninsula but also East Sea using data from both Korean Peninsula and Japan Islands. Accorging to the results, subduction zone starting from eastern part of Japan seems to be extended to the region beneath the East Sea.

• 한국해양학회지
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• v.30 no.4
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• pp.271-278
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• 1995

A study of heavy mineral sands in terms of heavy mineral group and concentration has been carried out by analyzing 88 grab samples from the continental shelf off the southeast coast of Korea. Heavy mineral groups seem to be outlined and classified into four regions in the study area: 1) the western region; high concentrations of stable minerals, such as opaque mineral, magnetite, garnet and ZTR, 2) Korean Trough region; moderate concentrations of stable minerals, 3) the eastern region; abundant altered mineral and amphibole with minor of pyroxene concentration, and 4) the northeastern shelf-break region; low concentration of stable minerals with abundant altered minerals. The sedimentologic natures of four major heavy mineral regions (groupings) seem to be influenced by physical, dynamic and hydraulic milieu and also aerial and/or subaqueous weathering processes. It seems to be, further, plausible that shallow marine waves and currents associated with neritic dynamic condition of transgressive sea might be very effective on the concentration and groupings (sorting) of heavy min-erals in the surficial sediments of the continental shelf. The pyroxene-abundant heavy mineral suite (group), in fact, seems to suggest a sediment source from Japanese Islands.

• Parasites, Hosts and Diseases
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• v.56 no.6
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• pp.589-596
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• 2018

Ticks are the vectors of various pathogens, threatening human health and animal production across the globe. Here, for the first time we detected Ricketssia spp., Borrelia spp. and protozoan in ticks from Poyang Lake region in Jiangxi Province of eastern China. In 3 habitat categories and on 12 host species, 311 ticks from 11 species were collected. Haemaphysalis longicornis was the predominant species, accounting for 55.63%, followed by Rhipicephalus microplus, Haemaphysalis flava and Ixodes granulatus. Of the collected ticks, 7.07% were positive for tick-borne pathogens, and H. longicornis and H. flava were found to be co-infected with Ricketssia spp. and protozoan. H. flava was the most detected positive for tick-borne pathogens, whereas H. longicornis had the lowest infection rate, and the difference in infection rates between tick species was significant (${\chi}^2=61.24$, P<0.001). Furthermore, adult ticks demonstrated remarkably greater infection rate than immature ticks (${\chi}^2=10.12$, P=0.018), meanwhile ticks on Erinaceidae showed significantly higher positivity than ticks collected on other host species (${\chi}^2=108.44$, P<0.001). Genetic fragment sequencing and analyses showed at least 4 pathogen species presence in ticks, namely Borrelia yangtzensis, Rickettsia slovaca or Rickettsia raoultii related genospecies, Babesia vogeli and Hepatozoon canis or Hepatozoon felis related genospecies. The finding indicates that the abundant ticks can carry diverse pathogens in Poyang Lake region, and pathogen infection is highly related to species, vertebrate hosts and life stages of ticks.

• Journal of Urban Science
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• v.9 no.2
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• pp.21-30
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• 2020

The purpose of this study is to present a plan to distinguish 229 local governments nationwide by taking into account various characteristics such as population, employment, housing, and industry of the region for customized urban policies in the era of metropolitan areas. The National Statistical Portal (KOSIS) collected and standardized data related to population, housing, industry, and finance by region from 2000 to 2015 for the classification of regional types necessary for customized urban policies, and this was used to classify them into regional types that considered population, employment, housing and industry. The summary of the analysis results is as follows. First, as a result of the regional type classification, 10 key employment sites (4.4%), 5 employment centers (2.2%), 38 residential centers (16.6%), 20 growth areas (8.7%), 26 industrial cities (11.4%), 35 low-fertile farming and fishing villages (15.3%) and 95 stagnant areas (41.5%). Second, the Seoul metropolitan area is the most diverse type of metropolitan area in the country, with most of its core employment sites inside Seoul, residential centers inside and outside Seoul, and growth areas in the southeastern part of the country (Busan, Ulsan, and Gyeongsangnam-do) are mixed with industrial and growth areas centered around Busan, Ulsan and surrounding areas, while the rest of the local governments are found to be low-fertile farming villages or stagnant areas. Daegu (Daegu, Gyeongbuk) is an industrial city in Daegu, and the rest of the local governments are either low-density farming and fishing villages or stagnant areas. The Honam region (Gwangju and Jeolla) was found to be a low-mill farming and fishing village or stagnant area except for Gwangju, while the Chungcheong region (Daejeon, Sejong, and Chungcheong) was seen as a growth area with areas adjacent to Daejeon, Sejong, and the Seoul metropolitan area, and some industrial cities were included. Finally, the Gangwon area was mostly classified as low-density farming and fishing villages and stagnant areas.

• Journal of Ecology and Environment
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• v.43 no.2
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• pp.117-128
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• 2019

Background: Cliffs are a major plant habitat around the coastal area, but in contrast to sand dunes and salt marshes, they have been little investigated in Korea. There are simple descriptions of cliff vegetation in studies on island vegetation, but there is no published paper, which addressed sea cliff vegetation synthetically. Furthermore, the coastal area where this study was carried out was designated as a conservation reserve. Even though, this area is exposed to intense recreational use such as trekking in these days. This study aims to clarify spatial distribution and structure of vegetation along the environmental gradient on coastal cliff and plateau in the Janggi peninsula (Homigot) located on southeastern Korea. Further, this study has also another objective to prepare a restoration plan to protect this conservation reserve from intense human disturbance. Results: Landscape elements were arranged in the order of sea cliff risen directly on the sea, seashore, coastal cliff, and plateau covered with relatively deep soil in a coastal area of the Janggi peninsula (Homigot), southeastern Korea. Vegetation was sampled at 59 plots arranged from the sea cliff through the seashore and coastal cliff to plateau. The sea cliff, seashore, and coastal cliff, which compose the coastal landscape, were dominated by the seashore spatulate aster (Aster spathulifolius Maxim.) community, dwarf sand sedge (Carex pumila Thunb.) community, and seashore spatulate aster (Aster spathulifolius Maxim.) community. On the plateau corresponding to the ridge of the coastal cliff, black pine (Pinus thunbergii Parl.) community, golden rain tree (Koelreuteria paniculata Laxmann) community, east Asian hackberry (Celtis sinensis Pers.) community, sawleaf zelkova (Zelkova serrata Makino) community, and Korean oak (Quercus dentata Thunb.) community were established in the mentioned order along distance from the sea. Stand ordination showed a vegetation sequence from the seashore through the cliff to the plateau, consistent in its overall pattern among sites. This was dominated by topography. There is evidence for the importance also of salinity, drought and of soil depth. Conclusion: The lack of scientific interest in cliffs to date is in striking contrast to the commonness of cliffs around the whole national territory and to the attraction cliffs have had for humans throughout history. Cliffs provide a unique habitat, rarely investigated from an ecological viewpoint. Cliffs may represent an invaluable type of ecosystem, consisting of some of the least disturbed habitats on earth and contributing more to the biodiversity of a region than their surface coverage would indicate. Although this coastal area where this study was carried out was designated as a conservation reserve, this area is in danger of severe disturbance due to excessive recreational use. We recommended a restoration plan to protect this area from such a disturbance.

• 한국지구물리탐사학회:학술대회논문집
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• 2002.09a
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• pp.46-66
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• 2002

High-resolution multichannel seismic data were collected in the coastal area near the Gori nuclear power plant to investigate Quaternary fault pattern and timing. A 12 channel streamer, a sparker, and a portable recorder were used for data acquisition. Because the group interval of the streamer was 6.25 m and the sparker can generate acoustic waves with the frequency content of up to 500 Hz, the data show a significant improvement both in horizontal and vertical resolution. The area surveyed is covered with 30-40 m thick Holocene sediments that constitute the mud belt along the southeastern coast of Korea. The survey area is characterized by the well discriminated Pleistocene and Holocene boundary and shallow gas-charged zones. A number of Quaternary faults were found in the sediment column, that are nearly vertical and extend north-south. The Quaternary faults, arranged at a spacing of a few hundred meters, suggest that they were formed in response to compression, although some of them reveal extensional characteristics. Locally, faults disrupt Incised-channel fills that are interpreted to have formed in the early stage of transgression after the beginning of the Holocene. Seismic sections suggest that shallow gas in the mud belt sediments made its way upward through the fractured fault planes. The tectonism responsible for the opening of the East Sea has not persisted since the late Miocene, but vigorous Quaternary faulting activity in the vicinity of the southeastern Korean Peninsula indicates that tectonic stability has yet to be achieved in this region underlain by the hotter than normal mantle.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.8 no.4
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• pp.369-379
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• 2003

Analysis of high-resolution seismic profiles and sediment data from the southeastern continental shelf of Korea reveals that the late Quaternary deposits consist of a set of lowstand (LST), transgressive (TST), and highstand systems tracts (HST) that corresponds to the sea-level change after the Last Glacial Maximum. LST (Unit I) above the sequence boundary consists of sandy mud or muddy sand deposited during the last glacial period and is confined to the shelf margin and trough region. TST (Unit II) between transgressive surface and maximum flooding surface consists of sandy sediments deposited during the postglacial transgression (15,000-6,000 yr BP). Although TST is widely distributed on the shelf, it is much thinner than LST and HST. On the basis of distribution pattern, TST can be divided into three sub-units: early TST (Unit IIa) on the shelf margin, middle TST (Unit IIb) on the mid-shelf, and late TST (Unit IIc) on the inner shelf, respectively. These are characterized by a backstepping depositional arrangement. HST(Unit III) above the maximum flooding surface is composed of the fine-grained sediments deposited during the last 6000 yrs when sea level was close to the present level and its distribution is restricted to the inner shelf along the coast.