• Title/Summary/Keyword: dominant period

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A Study on the Corelation between the Variation of Land Cover and Groundwater Recharge Using the Analysis of Landsat-8 OLI Data (Landsat-8 위성을 통한 토지피복 변화와 지하수 함양량 상관성 고찰)

  • Park, Seunghyuk;Jeong, Gyo-Cheol
    • The Journal of Engineering Geology
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    • v.30 no.3
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    • pp.347-378
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    • 2020
  • Based on monthly average groundwater recharge over a nearly 10 year period, results of fully integrated hydrologic modeling of SWAT-MODFLOW, land cover, land use, soil type and hydrologic response unit (HRU) was used to assess the dominant influencing factors of groundwater recharge spatial patterns in Jangseong district. As dominant factors, land cover was FRSE (forest-evergreen) and soil type was Samgag. Landsat-8 OLI imaging spectrometer data were acquired in the period 2003 to 2004 and seasonal bare soil lines (BSL) were estimated through NIR-RED plot. Extent of slope of BSL was from 1.092 to 1.343 and the intercept was from -0.004 to -0.015. To know correlation between spatial groundwater recharge and soil-vegetation indices (PVI, NDVI, NDTI, NDRI), this study employed frequency and regression analysis. On May, RED band increased up 3 to 4 times compared to other seasons and only one turning point appeared as recharge-index with upward parabola bell shape as results of existing research. Considering precipitation, if the various studies for relationship between groundwater recharge and soil-vegetation index just like NDVI are performed, it is possible to estimate groundwater recharge through analyzing remote sensing data.

Community Structure and Distribution Pattern of the Pleuronectiform Fishes in the Uljin Marine Ranching Area, Korea (울진바다목장에서 어획된 가자미목(Pleuronectiformes) 어류의 군집구조 및 공간분포)

  • Yoon, Byoung Sun;Park, Jeong-Ho;Sohn, Myong Ho;Yang, Jae Hyeong;Yoon, Sang Chul;Choi, Young Min
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.4
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    • pp.413-423
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    • 2013
  • To elucidate the variation of species composition, biomass and length distribution of flatfishes by the period and region in the Uljin marine ranching area, bottom trawl survey was investigated at the six stations from Feb. 2008 to Dec. 2010. During the survey period, a total 4 families 17 species in the Pleuronectiformes, average 69,158 $ind./km^2$ and 5,625 $kg/km^2$ were identified, in 2008 appeared in 14 species, average 25,798 $ind./km^2$ and 2,333 $kg/km^2$ and in 2009 appeared in 13 species, average 102,360 $ind./km^2$ and 5,634 $kg/km^2$ and in 2010 appeared in 14 species, average 75,704 $ind./km^2$ and 8,632 $kg/km^2$. The individual dominant species, occupying over 10% of total individuals, was Pleuronectes herzensteini (20,811 ind., 30.0%), Hippoglossoides pinetorum (18,666 ind., 26.9%) and Glyptocephalus stelleri (13,499 ind., 19.4%) also the biomass dominant species, occuping over 10% of total biomass, was P. herzensteini (2,207 kg, 39.3%), Pleuronectes yokohamae (857 kg, 15.3%), H. pinetorum (761 kg, 13.5%), Kareius bicoloratus (677 kg, 12.1%). From the cluster and MDS analysis based on Bray-Curtis similarity matrix of fourth root transformed data of species number and individuals in the Uljin marine ranching area from Feb. 2008 to Dec. 2010 was divided into two different groups of the flatfishes community in 2008 and from Jan. to Apr. in 2009 and 2010 (Group A) and the pleuronectiform community in from May to Dec. in 2009 and 2010 (Group B). From the cluster and MDS analysis using the similarity of demersal organisms community among six stations, the Uljin marine ranching area was divided into two different groups of Group 1 (St. 1 and St. 3) and Group 2 (St. 2, St. 4, St. 5 and St. 6).

Mobilization of Gookmin, Formation of 'Gookmin': A Historical Study of the Discourse of 'Gookmin' in Korea (국리의 동원, '국민'의 형성: 한국사회 '국민' 담론의 계보학)

  • Jeon, Gyu-Chan
    • Korean journal of communication and information
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    • v.31
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    • pp.261-293
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    • 2005
  • This article aims at investigating the origin of 'gookmin', which is currently working as the dominant discourse and leading identity in the South Korean society. Like 'nation', 'people' or/and 'citizen', the term of 'gookmin' is a very much particular and historical outcome of the colonial modernity. Nevertheless, however, there have been not so much serious socio-linguistic, cultural-political studies about its root. It is theoretically as well as practically quite important to trace back the birth of 'gookmin', which is working as an ideological, epistemological frame in/between subject and reality. In this regard, this article will consider the late Japanese colonial period as a key period of the birth of 'gookmin'. It will then critically scrutinize how the total mobilization system by adopted the colonial government has formed the discourse and subjectivity of 'gookmin' based on various physical apparatuses. By revealing that a totalistic nation/state of Japanese colonialism is behind 'gookmin', which wanted to mobilize every individuals into a so-called article of empire, this article tries to show the fascist and propaganda nature of 'gookmin' continuing even after the liberation. As a historical-materialist work of deconstruction the dominant discourse of 'gookmin', this study will basically take a cultural studies approach.

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Spatial and Temporal Changes of Fish Community in the Cheonggye Stream after the Rehabilitation Project (복원된 청계천에 서식하는 어류군집의 시공간적 변화)

  • Choi, Jun-Kil;Byeon, Hwa-Kun;Kwon, Yong-Su;Park, Young-Seuk
    • Korean Journal of Ecology and Environment
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    • v.41 no.3
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    • pp.374-381
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    • 2008
  • Spatial and temporal changes of fish communities were studied at four study sites in the Cheonggye Stream from October 2005 to August 2006 after the rehabilitation process. During the survey period, 19 species in 6 families were sampled. Species Rhynchocypris oxycephalus and Zacco platypus were identified as dominant species. Korean endemic species such as Acheilognathus yamatsutae and Zacco koreanus were observed in the sites. Overall, species richness and abundance increased as time passes after the rehabilitation, reflecting colonization process of the fish community. Meanwhile species richness and abundance were higher at the downstream than at the upstream. Community indices such as dominant index, richness index and diversity index showed also similar spatial and temporal pattern. Nonmetric multidimensional scaling (NMDS), multivariate ordination technique, was used to analyze spatial and temporal variation of the fish communities, and the results showed spatial variation of fish communities with high species richness at downstream as well as the temporal variation of fish communities with high values of species richness and diversity index at later part of the study period, presenting colonization process of the fish community after the rehabilitation project.

Basic Studies on the Breeding of Fiber Flax (Linum usitatissimum L.) in Korea (섬유용 아마(Linum usitatissimum L.)의 육종에 관한 기초적 연구)

  • Kyu-Yong Chung
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.19
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    • pp.83-99
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    • 1975
  • The earliness to flowering was completely dominant over the lateness, and the short plant height and stem length were partially dominant over the tall. The heavy stem weight, however, was recessive to the light. Heritability values for the flowering period, plant height, dry stem weight and fiber ratio were high, while those of days to initial flowering, stem length and fiber weight were low. Flowering period, plant height, stem weight, dry stem weight and fiber ratio were closely related to fiber weight or fiber yield. The selection index estimated jointly the plant height ($X_1$), dry stem weight($X_2$) and fiber weight($X_3$); that is 0.0020$X_1$-0.0047$X_2$-0.0181$X_3$, was the most efficient one for the selection practices. The plant height was the most reliable character for the increased genetic advances and the relative selection efficiences. Effects of locations and genotype-environment interactions were highly significant in most of the characters investigated.

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Characteristics of Microbial Distribution of Nitrifiers and Nitrogen Removal in Membrane Bioreactor by Fluorescence in situ Hybridization (막/생물반응기에서 Fluorescence in situ Hybridization 기법을 이용한 질산화 미생물 분포특성 및 질소제거 연구)

  • Lim Kyoung-Jo;Kim Sun-Hee;Kim Dong-Jin;Cha Gi-Cheol;Yoo Ik-Keun
    • Microbiology and Biotechnology Letters
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    • v.34 no.3
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    • pp.257-264
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    • 2006
  • An aerobic submerged membrane bioreactor (MBR) treating ammonium wastewater was studied in respect of nitrification characteristics and distribution of nitrification bacteria over a period of 350 days. MBR was fed with ammonium concentration of 500-1000 mg $NH_4-N/L$ at a nitrogen load of $1-2kg\;N/m^3{\cdot}d$. Overall ammonium oxidation rate increased with dissolved oxygen (DO) concentration, temperature, and sludge retention time (SRT). Under a higher concentration of free ammonia ($NH_3-N$) due to the decrease of ammonium oxidation rate, the nitrite ratio ($NO_2-N/NO_x-N$) in the effluent increased. The sudden collapse of nitrification efficiency accompanied by sludge foaming and the increase of sludge volume index (SVI) was observed unexpectedly during the operation. At the later stage of operation, additional carbon source was fed to the MBR and resulted in twice higher value of SVI and the decrease of ammonium oxidation rate. In fluorescence in situ hybridization (FISH) analysis, genus Nitrosomonas which is specifically hybridized with probe NSM156 was initially the dominant ammonia oxidizing bacteria and the amount of Nitrosospira gradually increased. Nitrospira was the dominant nitrite oxidizing bacteria during whole operational period. Significant amount of Nitrobacter was also detected which might due to the high concentration of nitrite maintained in the reactor.

Studies on the Floristic Composition and Periodicity at Joomoonjin Sea Bank (주문진(主文津) 인공(人工) 방파제(防波堤)에 서식(棲息)하는 해조상(海藻相) 및 주기성(週期性)에 관한 연구(硏究))

  • Kim, Yang-Bae
    • Journal of Fisheries and Marine Sciences Education
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    • v.3 no.2
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    • pp.29-46
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    • 1991
  • Benthic marine algal community of a sea bank at Joomoonjin, in the eastern coast of Korea, was investigated monthly in view of floristic composition and seasonal periodicity during from August, 1989 to July 1990. Total number of benthic alga identified were 70 taxa, which composed of 7 species of Chlorophyta, 21 species of Phaeophyta and 42 species of Rhodophyta. The dominant species were Sargassum horneri, Underia pinnatifida, Laminaria japonica and Pachymeniopsis sp.. Vegetation, from the point of phygiognomy, was a mosaic type by these dominant species. The flora was compared with similarity index using S${\phi}$rensen coefficient and grouped by a cluster analysis. As a result, the algal community of this area could be divided into two clusters at similarity level 45% : Flora of water temperature-ascending period(January-July) and flora of water temperature-descending period(August-December). And also, the former flora was subdivided into two clusters at point of the $14^{\circ}C$ sea water temperature : winter flora(January-April) and spring-summer flora(May-July). The flora of this area was characterized as a mixed flora of cold and temperature zone by Cheney's index.

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A seasonal characteristic of fish assemblage in the coastal waters Gapa-do, southern part of Jeju Island (제주도 남부 가파도 연안 어류군집의 계절별 특성)

  • KO, Jun-Cheol;HAN, Song-Heon;KIM, Bo-Yeon;CHOI, Jung-Hwa;HWANG, Kang-Seok
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.57 no.1
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    • pp.10-24
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    • 2021
  • A seasonal characteristic of fish assemblages in the coastal waters of Gapa-do was determined using samples collected by a trammel net from 2015 to 2019. Annual mean temperature and salinity were 18.9℃, 33.6 psu (2015), 19.5℃, 33.6 psu (2016), 18.9℃, 33.8 psu (2017), 18.8℃, 34.5 psu (2018) and 19.5℃, 33.7 psu (2019), which show a stable water mass. During the survey period, a total of 50 species (30 families and 8 orders) of fishes were identified, including Scorpaeniformes (3 families and 9 species) and Perciformes (18 families and 29 species) that accounted for 68% of the total number. The number of species was higher in summer than in winter, showing the peak in the summer by 35 species and the low in the winter by 20 species. The number of individuals and the biomass peaked in the summer by 690 individuals and 151.4 kg, and were the lowest in the autumn by 336 individuals and 76.6 kg. The annual diversity index, evenness index and richness index were appeared to be 2.54-2.75, 0.68-0.76 and 5.32-6.65 at each stations. The dominance index was appeared to be the highest in 2018 and the lowest in 2015. Marbled rockfish (Sebastiscus marmoratus), rock fish (Sebastes inermis), filefish (Stephanolepis cirrhifer), rabbit fish (Siganus fuscescens), porcupine fish (Diodon holocanthus) and smallscale blackfish (Girella melanichthys) were dominant species, which occurred abundantly during the entire survey period. Subtropical fishes were identified as a total of 24 species (48.0%) and the number of species was higher in 2019 by 20 (60.6%) species and lower in 2015 by 13 (44.8%) species. The dominant species of the subtropical fishes were appeared to be rabbit fish, porcupine fish, smallscale blackfish, flag fish (Goniistius zonatus), stripey (Microcanthus strigatus), grunter (Parapristipoma trilineatum), and bluestriped angelfish (Chaetodontoplus septentrionalis) at the study sites.

Dynamics and Seasonal Succession of Dinoflagellate Community in Masan Bay, Korea (마산만(馬山灣)의 와편모조류(渦鞭毛藻類) 군집(群集)의 동태(動態) 계절적(季節的) 천이(遷移))

  • LEE, JOON-BAEK;YOO, KWANG-IL
    • 한국해양학회지
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    • v.25 no.2
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    • pp.106-116
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    • 1990
  • The dynamics and seasonal succession of dinoflagellate community, and their correlations with environmental parameters were investigated during the period from April, 1986 to March, 1987 at 6 selected stations in Masan Bay, Korea. The dinoflagellate standing crops varied extensively with months and stations: ranging from 44 to 2,789,900 cella/ l at surface layer and from 52 to 165,714 cells/ l at bottom layer, respectively. The distribution of standing crops by size class of dinoflagellate species showed that a group of 20-um size class was predominant throughout the present survey, since the most of dominant species have belonged to the size category. Among dominant species, Gyrodinium fissum was most dominant throughout the year in all sampling stations, particulary in June. Scripsiella trochoidea was predominant in May, Protoperidinium bipes and Prorocentrum minimum from June to September, Prorocentrum triestinum, P micans and Ceratium fusus from September to December, and Heterocapsa triquetra from December to April. The stepwise multiple regression analysis between dinoflagellate and environmental parameters revealed that salinity, nitrate-N, pH, and transparency were correlated with the variations of standing crops of dinoflagellate.

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Seasonal Variation in Species Composition and Biomass of Microphytobenthos at Jinsanri, Taean, Korea (한국 태안군 진산리 저서미세조류의 계절별 종조성 및 생물량 변화)

  • Park, Seo Kyoung;Kim, Bo Yeon;Choi, Han Gil;Oh, Joung-Soon;Chung, Sang-Ok;An, Kyoung-Ho;Park, Kwang-Jae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.2
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    • pp.176-185
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    • 2013
  • Seasonal species composition and biomass of microphytobenthos were examined at the intertidal flats of Jinsanri, Taean, Korea, from April to December 2011. In total, 121 species were identified, including 109 diatoms, 5 blue-green algae, and 5 dinoflagellates. Seasonal variation in species number ranged from 49 to 56 species (minimum in October and maximal in April), while vertical variation across three different shore levels ranged from 64 to 77 species with maximum at high and minimum at low shore. Species diversity ranged from 3.22 to 3.42 seasonally and from 3.50 to 3.17 across vertical shore levels. Seasonal average values of the normalized difference vegetation index and the vegetation index were 0.06 and 1.14, respectively. Chlorophyll a concentrations were $66.00-120.73mg/m^2$, with a seasonal minimum and maximum in July and October, respectively, and a vertical shore maximum of $137.35mg/m^2$ at mid shore. Phaeopigment concentrations peaked in October ($50.78mg/m^2$) and at high shore ($61.58mg/m^2$) and were lowest in December ($22.53mg/m^2$) and at low shore ($15.28mg/m^2$). The number of microphytobenthos ranged from 78,556 to 287,898 cells/$cm^2$, reaching a maximum in April and a minimum in July. The diatoms Paralia sulcata, Navicula sp., and Delphines surirella were dominant at all tidal levels over the study period. Dinoflagellates were dominant in July at low shore, and blue-green algae were abundant between July and October at mid shore. In conclusion, species composition and primary production of microphytobenthos exhibited clear seasonal and vertical patterns.